Our Changing World

Claire Concannon and Dr Andrew Digby talk about all things kākāpō: that habitat trial and where the birds are now, the next breeding season, and Andrew's hopes for the future of this iconic manu.

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In July 2023 four male kākāpō were released into the fenced Sanctuary Mountain Maungatautari - part of a new habitat trial to investigate suitable locations for the growing kākāpō population. But after a further six were introduced, the kākāpō began to wander - beyond the fence. A year on, and several escapes later, what's been learned? And what's next for kākāpō in Maungatautari?

There are plenty of night-time wanderers in New Zealand that you might expect to come across driving on back roads - rats, mice, a seemingly endless number of possums.

But it's not often that you round a corner to come face to face with a kākāpō.

Elwin's escapade

This was the surprising sight that faced Tyler James Lindsay very early one morning in January 2024.

A Cambridge local, Tyler was driving a milk tanker along Scott Road, northeast of Sanctuary Mountain Maungatautari, when suddenly he saw before him a strange shape.

"Just a big green bird. Just in the middle of the road looking straight at my lights, I think it was rather confused," he says.

Luckily, Tyler is into native birds, so he was aware that kākāpō had been introduced to the fenced sanctuary six months earlier. He knew exactly what he was looking at.

The next day, Tyler's report made its way to Sanctuary Mountain Maungatautari kākāpō ranger Dan Howie, who quickly began the search for the elusive Elwin.

"Such an incredible interaction that he saw this bird out there - in the middle of the road no less - which is absolutely terrifying as kākāpō ranger," says Dan.

But this was not the first time, nor the last, that Dan would feel that fear.

The habitat trial

Kākāpō numbers are growing. In 1995 there were just 51 kākāpō and the threat of losing them forever was all too real.

A decade ago, around the time that Dr Andrew Digby joined the Kākāpō Recovery team, there were just over 120 kākāpō. Today there are 247.

Intensive management and three quite successful breeding seasons have enabled this doubling of kākāpō numbers in the last 10 years. Initially, the challenge was to save the charismatic, flightless parrots from extinction. Now, the team also has an added challenge: where to put them.

To date, the majority of kākāpō have lived on offshore predator-free islands in the rohe of Ngāi Tahu - Whenua Hou / Codfish Island next to Rakiura / Stewart Island, and Pukenui / Anchor Island in Fiordland. But these islands are getting full. …

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An expedition to the Bounty Trough off the Otago Coast uncovers a treasure trove of deep-sea creatures - including some species new to science. Veronika Meduna meets slimy fish, snails, and tiny shrimp-like critters from the ocean depths.

The Bounty Trough is one of the world's least explored deep-ocean ecosystems.

Earlier this year, an expedition set off to explore this deep underwater rift valley off the Otago coast as part of the international Ocean Census project, under the umbrella of the United Nations Ocean Decade.

In partnership with Te Papa and NIWA, the voyage aimed to fill gaps in our knowledge of what lives in the deep.

Hundreds of new species discovered

Onboard the research vessel RV Tangaroa were different sets of traps and samplers as well as a deep-tow camera system to allow the scientists to watch what goes on at depths of up to 5,000 metres. The expeditioners returned with hours of video footage and 1,800 specimens. Hundreds of them are new to science - including a slender, slimy bottom-dwelling fish known as an eelpout.

The number of new fish species may be countable on one hand, but Dr Rachael Peart expects to identify several new small crustaceans known as amphipods and isopods. They look a bit like tiny shrimp and dominate life in the deep ocean.

Te Papa mollusc curator Kerry Walton has already identified 78 new species of snails and mussels from the Bounty Trough, including a parasitic snail stuck to a gummy squirrel - a weird sea cucumber with a large sail-like extension.

Te Papa fish curator Andrew Stewart says the museum's collection is limited to shallower depths of about 1,200 metres and mostly commercial species. Being able to explore the Bounty Trough opened up a treasure trove of sightings and catches from the deep.

It also brought home the importance of ocean life.

"This is the world's largest habitat, by a vast margin. It plays a massively important role," he says. "We really need to know what's down there because shifts down there are the canary in the coal mine. We lose those, we're in trouble. Maybe not today, maybe not tomorrow, but we're in trouble."

Why explore the deep sea?

Professor Alex Rogers, the science director of the Ocean Census programme, says there are many reasons why we need to know what lives in the deep.

About half of the oxygen we breathe is produced by tiny plants that live in the ocean. They also kick off the marine food web - from microorganisms to fish - which ultimately feeds millions of people. …

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Avocado seed powder to make snacks, fish waste skin for wound healing, and bioactive compounds made from brewer's spent grain - Claire Concannon visits a food lab at AUT turning food waste into wealth.

Food is usually a no-no in a science lab, but this lab at the Auckland University of Technology is different.

One fridge is labelled 'beer research'. There's a drawer full of stick blenders, and a coffee machine.

"Well, it is a food lab," says senior lecturer Dr Rothman Kam. "It would be quite sad if you do experiments and were not able to eat the food that you make."

Food scraps to snacks

Rothman and his food science lab group are interested in turning food waste into high value products (a process called 'food waste valorisation').

For example, tonnes of avocado seeds are a waste product of making avocado oil. Rothman and his team have set their sights on transforming seeds into snacks.

They've worked out a method of blending the seeds and processing them to make them fit for human consumption, resulting in an avocado seed powder.

This powder can then be added to breads or biscuits, or used with other grains to make puffy snacks.

Arti-fish-al skin for wound healing

A second project, led by PhD candidate Edward Quach, is investigating the use of fish waste products to create artificial skin. This skin can be loaded with drugs to help burn victims heal faster.

While the method of using fish gelatine in this way isn't new, Edward is trying a novel technique that bypasses the need to extract the gelatine, and instead goes straight from the freeze-dried ground-up fish waste to the jelly-like skin.

A second life for spent grain

The lab's 'beer research' focuses not on the alcoholic drink, but on the spent grain generated in the beer brewing process.

PhD candidate Ha Minh Quoc uses a freeze-drier to remove any moisture from the brewer's spent grain. Once he has dried out the grains, and ground them to a powder, he adds bacteria in. The bacteria (and the enzymes they contain) chop up proteins found in the grain, producing molecules with bioactive properties.

These bioactive molecules are small bits of protein (peptides) that can carry out many different important functions in our cells. For example, bioactive peptides might help fight off germs, reduce high blood pressure, lower blood fats, act as antioxidants, or help ward off obesity, diabetes or ageing. …

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Climate-change-induced sea level rise is happening. What will this mean for our low-lying wetlands? Will they get eroded away - releasing more carbon? Or will they grow at the same rate, and hold their ground? And what will this mean for the critters that live there? A team are investigating at an Otago wetland that might be the first in New Zealand to make this change.

From Lake Waihola, not far south of Ōtepoti Dunedin, fingers of water run down the plains, converging with the Waipori river coming from Lake Waipori.

Dr Chris Kavazos, a freshwater technical advisor for the Department of Conservation, stands in one of these fingers. Waders on, he rummages in the muddy bottom for a logging device that has sat there for the last four months.

Tracking the change

In that time, the device has been taking measurements of pressure and conductivity every ten minutes. From here, the water will complete its journey by joining the Waipori River, which connects with the Taiari (Taieri) river, and then empties into the ocean ten kilometres away.

But it's not just a one-way trip.

The area is extremely low-lying, just centimetres above sea level. Despite the distance from the coast, these waters experience tidal changes, and influxes of sea water. By measuring tiny pressure changes that equate to water depth, plus a conductivity reading that gives an indication of salinity, these logging devices are tracking the impacts of rising tides on these inland wetland areas.

As sea levels rise - a result of human-induced climate change - these wetlands might be the first in New Zealand to experience significant impacts. Chris and others are keen to understand what it might mean for the area, and its inhabitants.

The Waipori-Waihola wetland complex

From a map the approximately 2,500-hectare Waipori-Waihola wetland complex is easy to spot.

Two lakes mark the north and south boundaries. The darker patches of lagoons, pools, swampy areas and meandering channels that connect them are easy to distinguish from the bright green rectangles of cultivated land that form the borders.

And off a gravel road on the inland side of the wetland complex is a small collection of buildings – an office, accommodation, equipment sheds and a native plant nursery – this is the working space of Te Nohoaka o Tukiauau Trust…

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We might think deep-sea squid look a bit strange, but if they have the capacity for it, they would likely consider us monsters! Claire speaks to a squidologist and a PhD candidate about their research trying to understand more about the lives of deep-sea squid.

When you picture where creatures live on Earth, what do you see?

A tropical jungle? A highland pasture? An inland lake? Maybe a rocky seashore?

All of it combined - ecosystems on land, plus shallow coasts - makes up just 5% of the liveable space on our planet.

Instead, maybe you should be picturing somewhere dark, cold, and under hundreds of metres of water.

The deep-sea world

"If aliens would come to planet Earth and sample the habitats here to find out what our biodiversity is like, they could conceivably have to sample 95 times before they would find a habitat that was not deep sea," says Associate Professor Kat Bolstad from Auckland University of Technology.

This is why scientists are still finding new species of deep-sea squid.

When Kat says deep-sea, she means the part of the ocean below the sunlight ("photic") zone, where photosynthesis can take place. But even without sunlight, there are plenty of creatures down there making their own light though bioluminescence.

It's a very different world to our up-top, dry-air, UV-intense spaces, which makes it tricky for us to visit and study. You can lower submarines or equipment down there. But squid are alert to anything strange in their environment and tend to make themselves scarce.

Kat does make use of such exploration methods and has even been down to depths of 1,000 metres in a bubble submarine in the Antarctic herself. But to unravel the secret lives of squid, she also relies on other avenues. Like "squid Christmas".

'It's the most wonderful time of the year'

Every year, Kat and some of her research team travel to Wellington for "squid Christmas" - a clean out of NIWA's freezers that sometimes yields "presents" in the form of "squidsicles" - frozen squid specimens.

It's always a time of excitement.

"Anytime you look at samples from the deep sea, there's a reasonable chance that you will see something that no human has ever seen before," says Kat.

As well as NIWA, Kat collaborates closely with Te Papa and Auckland Museum, who also have marine collections filled with deep-sea treasures collected by research vessels on fishing surveys, biodiversity sampling, or discovery expeditions.

Focusing on squid eyes …

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Jump onboard an alpine flight to photograph some glaciers! The annual snowline survey has been running since 1977, but today new techniques are allowing researchers to go beyond 2D photos to make 3D models of the glaciers. Claire Concannon joins the team for a long day of flying and photographing.

It's a bright blue morning in Queenstown. Summer has been and gone, and the first hints of autumn are starting to appear. Leaves turning, a sharpness in the mornings, the first overnight frosts.

And as this shift begins, it's also time for another annual event - the end of summer snowline survey flight to monitor New Zealand's glaciers.

How to build a glacier

A glacier forms when snow builds up over time, turns to ice and then begins to flow downwards under the pressure of its own weight. For this to happen, you need snow accumulating.

The snowline is an imaginary line that traces along mountain slopes and marks the lower limit of permanent snow cover. Below this line, snow and ice melt away, above it, snow sticks around.

At the change of seasons, snow below this line from the previous winter will have melted, and if you time it right, and no new snow has fallen, you can fly a plane past a glacier and photograph the end-of-summer snowline. By repeating this each year, researchers can track changes happening to our glaciers over time.

'Trev used to run on excitement and liquorice'

The survey began in 1977. Back then, it was designed and led by a scientist called Trevor Chinn. After completing an inventory of all New Zealand's glaciers, and coming up with a total of more than 3100, Trevor realised that it just wasn't practical to monitor every individual glacier.

Instead, he developed a list of 51 'index' glaciers that would be surveyed each year. Using aerial photographs that showed the end of summer snowline height, they would be able to estimate ice volumes of the glaciers year-on-year - and keep an eye on changes.

Though the survey baton was passed on to Dr Drew Lorrey of NIWA in 2009, Chinn continued to go on the annual flights until his passing in 2018. As a nod to him, there's still a bag of liquorice opened and passed around on each flight.

"Trev used to run on excitement and liquorice," says Lorrey . "There's a really rich legacy that we've got to do justice to, in terms of carrying on, but also making sure that the science grows and that it actually is applied with a purpose." …

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A new six-part video series highlights the state of our oceans, and efforts from researchers, Māori and other partners to develop sustainable solutions.

Check out this new series of short video documentaries, Turning The Tide.

Across six episodes, Turning The Tide shows what's happening beneath the ocean surface, and highlights mahi across the motu to restore marine ecosystems.

We hear firsthand from researchers, iwi, hapū, community leaders and others who are coming together to devise sustainable solutions for the sea, and ensure healthy and resilient oceans for generations to come.

From kina barrens to restoring mussel beds to engaging rangatahi, Turning The Tide traverses a raft of fascinating marine stories that will take you deeper into our oceans.

Watch Turning The Tide on the RNZ website, RNZ Facebook page, or the RNZ YouTube channel.

Turning The Tide was made by Tauihu Media and funded by the Sustainable Seas National Science Challenge.

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Māori and Pacific peoples are three to six times more likely to develop stomach cancer than New Zealanders with European ancestry. Claire Concannon visits a research team taking aim at this disparity.

Dr Tom Mules wears two hats. He's a researcher at the Malaghan Institute for Medical Research, but he's also a gastroenterologist at Hutt Valley hospital. It's there that he meets patients suffering from stomach cancer.

"It's a horrible disease. A large number of people are diagnosed when the treatment options are limited, when it's too late for surgery," he says.

This is what has motivated him to take on his latest research challenge - one that he hopes will reduce stomach cancer rates and disparities in Aotearoa.

What's a bacterium got to do with stomach cancer?

Worldwide, stomach cancer was responsible for more than 660,000 deaths in 2022. In Aotearoa New Zealand it’s the eighth leading cause of cancer death for men. But when you look into the data, the picture gets more complicated. Māori and Pacific peoples are three to six times more likely to develop stomach cancer, and chances of survival are worse.

There are some well-established risk factors for stomach cancer, and one of these is infection with the stomach bacterium Helicobacter pylori (H. pylori). Many people around the world are infected with H. pylori, between 40–50% of the global population, and a lot of people are asymptomatic. However, in some people H. pylori can cause inflammation of the stomach lining, and, if left untreated, this can lead to tissue damage, ulcers, and eventually, for some people, stomach cancer.

As Tom explains, we don’t have up-to-date data on the rates of infection of H. pylori in New Zealand, the best information we have comes from a small South Auckland study from over a decade ago.

Looking at just shy of 600 people, the researchers found that around 30% of Māori and Pasifika had H. pylori infection, while for New Zealand Europeans it was just under 8%.

A team at the University of Otago is currently running a study to find out how common H. pylori is in New Zealand, so that we have better numbers.

The rise of resistance

Of course, because it is a bacterium, we can target it with antibiotics. The current strategy in New Zealand is a kind of scattergun attack: patients diagnosed with an infection will be given a mixture of three antibiotics to take. …

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Aotearoa is a country plagued by pests, but conservationists are hoping advances in drone technology could turn the tables. Producer William Ray looks at how drones are being trialled in controlling everything from microscopic diseases to elusive wallabies, and wilding pine trees.

A ghostly grey image appears on the laptop screen. "You see these deer?" asks Jordan Munn, pointing at a corner off the screen where a pair of animals are highlighted in bright white.

"I have directed a hunter to these deer. He's actually just shot this one, this deer to the right, and it's about to fall over," he says.

The brilliant silhouette of the first deer tumbles to the ground, the second follows a few moments afterwards.

Hunting with heat

Jordan is professional hunter and owns a company called Trap and Trigger based in Upper Hutt. The company has contracts with several regional councils for eliminating everything from deer to wallabies to wilding pines

And Jordan says there's a new technology revolutionising the industry - small commercially available UAVs (unmanned aerial vehicles), or as they are more often called: drones.

"We're becoming more and more reliant on them," Jordan says. "It's amazing how the pest control industry has reshaped in the last decade. Ten years ago, basically non-existent."

When mounted on a drone, the thermal vision of an infrared camera makes warm-blooded deer, wallabies and other mammalian pest species stick out like a sore thumb - even when the animal is mostly obscured by scrub.

A decade ago, Jordan says, even a thermal imaging camera or scope was beyond the budget of most commercial hunters. But costs have come down radically over the past decades, and they are still dropping.

"Within a few years, every contractor will have a thermal handheld camera and a thermal scope and a thermal drone. And if you don't have one of those or all of those, you're lagging behind," Jordan says.

It all seems very science fiction, and Jordan speculates it could be possible to use drone technology to remove the hunter from the equation entirely.

"We haven't yet got guns on them," Jordan says. "But if we could legally use a firearm from a drone safely.... It would work. It would work very well. But there will be a few issues, social issues and legal issues to get to that point."

While weaponised drones aren't likely to arrive in New Zealand any time soon, Otago Regional Council is already experimenting with fully autonomous drones for a different type of pest.

Tree terminators…

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Caves created by rivers of lava underlie New Zealand's biggest city. A new research project is documenting Auckland's lava caves, hoping to protect this hidden geological heritage and understand what future eruptions might have in store.

Known for its iconic maunga like Rangitoto and Maungawhau Mt Eden, Tāmaki Makaurau Auckland is a city built on an active volcanic field that has erupted at least 53 times.

But beneath streets, houses and parks, there are other - hidden - remnants of the city's fiery past: hundreds of lava caves.

The backyard cave

Lava caves form when hot flowing lava meets air and crusts over, creating a tunnel. Eventually the lava drains away, leaving behind a cavity.

Formed as far back as 200,000 years ago and as recently as 550 years ago (when Rangitoto erupted), lava caves in Auckland range from small cracks to lengthy tunnels. The longest, located in Wiri, stretches to 290 metres.

The lava cave in Sean Jacob's Mt Eden backyard is about 100 metres long. "For something that's so quiet and so peaceful when you're down here, it was sort of created by so much violence," he says.

The Jacob family bought the property in 2008 - in part so the cave would be protected, unlike many others across the city which have been destroyed or infilled with concrete in years gone by.

The speleologist

Peter Crossley is perhaps the only person who went inside some of those caves that no longer exist. A speleologist, Peter has spent 50 years documenting Auckland's lava caves.

"Some people would say that they're muddy, grotty, dark, infested with rats and all the rest of it. But when you look at it, you realise: it's a tunnel which has been filled with lava, almost yellow in heat, that could frazzle you in a microsecond," he says.

Over the decades, Peter has seen surveying methods advance from compasses to state-of-the-art 3D scanning, giving scientists unprecedented detail and valuable insights into past eruptions.

Now he's passed on his knowledge of 180 lava caves to a new research effort.

A new lava cave every month

Jaxon Ingold, a master's student at the University of Auckland, is collating everything we know about Auckland's lava caves - drawing on Peter's records, historical sources, and mātauranga Māori - so this geological heritage can be better protected and respected.

"What I'm currently working on is: is it possible to predict where as-yet undiscovered lava caves may be located? So that we can be more careful in those areas," says Jaxon. …

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A deadly frog fungus has decimated frog populations around the world, but frog biodiversity hotspot Papua New Guinea remains untouched - for now. In this episode of ABC podcast Pacific Scientific, James Purtill discovers the amphibian treasures of the world's largest tropical island, and what conservationists are doing to protect them.

Frog populations around the world have been decimated by a deadly fungus. But one place that has remained unaffected - so far - is Papua New Guinea.

It's home to the world's most diverse array of tropical frogs, including many species unknown to science. Conservationists are racing to safeguard these amphibian treasures before the fungus inevitably reaches Papua New Guinea.

The frog-killing fungus

The deadly fungal pathogen, called chytrid fungus, has swept around the world in recent years, causing mass mortality in some frog species and populations.

Chytrid fungus has been detected in New Zealand in both introduced and native frogs. It might be one factor behind the decline of the endangered Archey's frog, but its impact here is still not well understood.

When the worldwide chytrid epidemic began to accelerate in 2015, Yolarnie Amepou from the Piku Biodiversity Network in Papua New Guinea joined a search for the fungus. No evidence of chytrid was found, but scientists believe it's just a matter of time before the pathogen arrives on the world's largest tropical island.

A frog paradise

Papua New Guinea is home to rare and unique species, with many still unknown to science. In this episode from the ABC podcast Pacific Scientific, reporter James Purtill joins Yolarnie and her friend Heather for a frog hunt in the jungle near the capital city, Port Moresby.

James also checks out a captive frog facility where conservationists are raising an insurance population for if - or when - chytrid fungus hits.

Pacific Scientific is a podcast series covering science and scientists from across the Pacific. It is a co-production between ABC Science and Radio Australia. This episode was reported by James Purtill and produced by Tamara Cranswick.

James spoke to Yolarnie Amepou, director of the Piku Biodiversity Network, and Ryan Reuma, wildlife officer at the Port Moresby Nature Park.

The series producer is Jordan Fennell and executive producer is Will Ockenden. Jonathan Webb is the ABC science editor.…

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This week, Phil Vine dives into the science of climate attribution. How much is climate change affecting extreme weather events? And how can this new science prepare us for the future?

For a long time when asked this question, climate scientists simply shook their heads.

They had been telling people that global warming was making many storms, floods, and weather events worse - but when asked: "by how much?" - they didn't have an answer.

Then one day Oxford University physics professor, Myles Allen, experienced one of those extreme weather events.

As the River Thames flooded and threatened to pour water through his kitchen door, on the radio the Met Office was saying it was impossible to accurately link the event with climate change. He said to himself: "we need to do better than that".

Famously, rather than search out sandbags to keep the floodwaters at bay, he sat down and wrote a journal article - making that connection between global warming and specific weather events.

And a branch of science was born: extreme event attribution studies, or climate attribution for short.

In Aotearoa, there's a whole gang of scientists from different institutions carrying out world-leading research in this new field.

2023: the year of storms

Few in the upper North Island will forget the beginning of 2023.

The Auckland Anniversary Floods arrived at the end of January. Four people dead. Seven thousand homes damaged.

Less than two weeks later came Cyclone Gabrielle. Eleven people killed. A staggering 850,000 landslides.

After Cyclone Gabrielle, Dr Luke Harrington from the University of Waikato and an international team from the World Weather Attribution project worked round the clock on rainfall data and climate models.

They were endeavouring to find out if, and how, climate change had affected the devastating tropical cyclone.

And they broke with scientific tradition. Rather than wait and publish a paper in a year's time, they sought to get a report out while Cyclone Gabrielle was still in the news.

"If it's 12 to 18 months after the event happened, the public doesn't really care," says Luke.

The project team worked out that 10-15 per cent more rain fell because of global warming.

"It demonstrates that climate change isn't a future problem. It is not something that you are going to see play out in 50 years' time, it's already playing out now," Luke says.

The cost of climate damage …

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Could the answer to one of our most pressing health needs be hiding in Aotearoa's bush? On Our Changing World this week, Liz Garton heads out on a foray to discover some of our fungal gems, and she finds out what we're doing to uncover their potential antibiotic properties.

Could the answer to the global problem of antibiotic resistant bacteria be in our backyard?

It's a question being given serious time and consideration by Dr Siouxsie Wiles and Dr Bevan Weir, with help from fungi enthusiasts around Aotearoa.

The problem

The World Health Organization describes antimicrobial resistance as one of the top global public health threats, responsible for an estimated 1.27 million deaths in 2019.

"Life is always fighting, so bacteria will find a way to fight against antibiotics," says Dr Bevan Weir, head of Mycology and Bacteriology Systematics Research at Manaaki Whenua / Landcare Research. "They'll evolve chemistry to cut the molecule and render it inactive or other forms of resistance - they can change their cell walls and pump out the antibiotic more."

"They're always finding a way to evolve around antibiotics, so we do need to find more," he says.

The foray

On a cool but sunny autumn morning in May 2023, Liz Garton joined The Fungal Network of New Zealand's annual foray at Maungatautari Sanctuary Mountain. The 2024 fungal foray is taking place now, from 12-18 May in Havelock.

Each year the foray is held in autumn when the fungi fruits, and it can be spotted.

Each fungus begins as a miniscule spore. From that grows the mycelium, a network of fungal strands, like string, and from those you get the fruiting body. The fruiting body is the bit we see sprouting out of the ground, or whatever the organism is growing on - what we call a mushroom.

Bevan says one of the main reasons for the foray is to take samples for the national culture collection (which he curates) and to try identify and describe what is found.

"That's one of the big questions we don't know; what fungi is native and what are not," he says. "We have probably only described or identified about a third of the fungal biodiversity in New Zealand."

With that unidentified diversity comes diversity of chemistry too. A fungus growing on a piece of wood needs to defend itself and compete with bacteria.

"So it will be producing an antibacterial to kill that bacteria and we might be able to discover what that is and use it for us in a medical context," says Bevan.

The (possible) solution

This brings us to the work Bevan is doing with microbiologist Dr Siouxsie Wiles at the University of Auckland…

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A multi-year research project aims to find out the risks from two Bay of Plenty offshore island volcanoes: Tūhua / Mayor Island and Whakaari / White Island

In the National Isotope Centre in Gracefield, Jacqueline Grech Licari is bent over half a sediment core section, carefully looking for a dark line of ash - a clue left behind by Whakaari, a volcanic island in the Bay of Plenty.

Tracing the history of past eruptions

Jacqueline is a PhD candidate at Te Herenga Waka Victoria University of Wellington using sediment collected from the seabed around Whakaari, White Island, and its neighbour, Tūhua, Mayor Island to investigate their eruptive pasts.

Layers of ash - also called tephra - are carefully logged and sampled. Chemical analysis identifies exactly which volcano it came from, while the thickness of the layer gives hints at the eruption's size.

With 38 cores taken from the seabed around both these volcanic islands, Jacqueline has a lot of work to do. But she's hoping to be able to build a picture of the frequency, timing, and scale of previous eruptions. And, importantly, how widespread the effects were.

Her work will feed into the wider Beneath the Waves programme - a five-year research project led by GNS Science to investigate these two nearshore island volcanoes.

The anatomy of a volcano

The overall goal of the programme is to identify the full extent of the risks these active island volcanoes might pose to mainland communities.

Could they trigger tsunamis that would impact the coastline? Might ash make it across the ocean buffer and cause air quality and soil problems? And at what frequency might eruptions of this scale occur?

One aspect of the project has been to map the anatomy of the two volcanoes.

Using sensors that can detect changes in the conductivity of the rocks in the crust, the researchers are able to reconstruct a 3D map of the pluming of the volcanoes - where the magma chambers, and hydrothermal systems (the paths that water heated by the magma takes) are. GNS Science geophysicist Dr Craig Miller hopes this will give context to future monitoring and help them better interpret any signals they see.

This mapping will also enable them to look for any spots in the seabed floor weakened by volcanic activity that might have the potential to slide and cause a tsunami when an eruption occurs.

Listen as Craig explains to Claire Concannon the differences between the two volcanoes, and how the team hopes this research will help with hazard mitigation. …

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Meet two winners of the 2023 Prime Ministers Science Prizes. In the wake of the 2019 Whakaari eruption, Professor Ben Kennedy engaged communities with the science of volcano hazards - mahi that earns him the 2023 Science Communication Prize. Meanwhile, Future Scientist prizewinner 17-year-old Sunny Perry has developed a helpful soil map.

When Sunny Perry decided to make a map identifying locations of corrosive soil around Northland, she didn't foresee the extra benefits.

Winning the 2023 Prime Minister's Future Scientist Prize was a big one. Heaps of driving practice with her dad - which helped her pass her driving test - was another.

But there were downsides too: 5am starts, turning her bedroom into a chemistry lab, and having to let her dad pick the road trip tunes. "There were some very questionable choices sometimes," Sunny says.

Road tripping for soil samples

In total, the duo visited 20 sites across Northland: from north of Kaitaia, all the way south to Mangawhai, and across to the west coast.

At each site, Sunny took triplicate soil samples at different depths which she then brought back to her makeshift chemistry lab to test for the presence of a certain type of soil - one that has the potential to cause damage to the environment and infrastructure if disturbed.

An aggressive soil

You may not have heard the term "acid sulphate soil", but Whangārei District Council certainly has. This soil was the culprit behind corrosion of concrete pipes in the Marsden City development at Ruakākā, which cost ratepayers $5 million. Auckland Airport is aware too, since it had to add eight tonnes of lime to a stream on its property in 2016, after plants started to die around it.

These acid sulphate soils can form in waterlogged areas devoid of oxygen and rich in organic matter. They contain crystals of pyrite - iron sulphide minerals. When they lie undisturbed, they are safe and harmless.

But, if they are dug up or drained, and exposed to oxygen, the pyrite in the soil reacts with the oxygen, producing sulphuric acid. The acid lowers the pH of the soil, which can cause damage to plants, creatures, and infrastructure.

Where are these soils found?

To avoid disturbing these soils, you need to know where they are likely to be.

That's what Sunny set out to determine. Using knowledge of the conditions needed for these soils to form, mapping skills developed throughout the project, and her soil sample testing, she has created a map of Northland which shows where these acid sulphate soils might be.

Sunny hopes it can be used to make good decisions about land management across Northland. …

Go to this episode on rnz.co.nz for more details

Kate Evans visits a passionate team as they carpet a remote volcanic island in Tonga with poisoned bait, hoping to eradicate rats. What does it take to complete this kind of project, what are the chances of success, and what will it mean for the island's ecosystems if they manage to remove the rats once and for all?

Rat eradication from islands is a team sport. It's not a competition - but if it were, New Zealand would surely be up there. That's why on most pest removal teams around the world you can probably find one or two Kiwis right in the thick of things.

It takes a village

A team lined up to complete the rat eradication project for the island of Late in the kingdom of Tonga is no different. The New Zealand Department of Conservation is supporting the operation and have provided some skilled staff. The helicopter team (pilot, engineer, ground crew) are all Kiwi too.

They're joined by a project manager from the NGO Island Conservation, and Tongan conservationists from the national environment department.

Years of feasibility studies, finding funding, planning and logistics have come down to this - a second, and final, aerial application of poisoned bait across the island.

Island paradise

It may not be what you picture when you think of a tropical island, but its jagged basalt cliffs and remoteness has made volcanic Late a potential wildlife haven.

Here you can find the Tongan whistler and ground dove, two rare birds on the IUCN red list of threatened species. And it has the habitat needed for the malau - the Tongan megapode - to breed. Malau don't incubate eggs by sitting on them, instead they bury them in warm volcanic soils and sands, and Late's smoking surface is perfect.

Rat eradications elsewhere have allowed forests to rejuvenate, land birds to rebound and seabirds to return. The bird guano ripples the effect out further - feeding the coral reefs and allowing nearby ocean ecosystems to flourish.

Science journalist Kate Evans joins the team on the last day of bait spreading, in what they hope will be the first day of a bright future for the island and its inhabitants. …

Go to this episode on rnz.co.nz for more details

Journalist Rebekah White meets two people who have been counting albatrosses on remote islands in the subantarctic for more than three decades. Their research shows that at least one species is en route to extinction. A few changes to the way we fish could save it.

Gibson's and Antipodean albatrosses are citizens of no one nation. They are ocean birds, living on the wind and waves, travelling massive distances, passing back and forth over the high seas and the imaginary boundary lines we draw on maps.

But when they land to chat, to flirt, to lay an egg and raise a chick, they come to two of New Zealand's subantarctic islands.

Three decades of albatross study

And when they return, some of them meet with two familiar human faces.

Across the last 34 years, Department of Conservation researchers Kath Walker and Graeme Elliott have been visiting these islands to count the birds, and to study them.

At first everything seemed fine. In the early 1990s numbers were low but increasing. Things were positive. Then came the summer of 2006/2007. There was a population crash, reason still unknown, and on both islands, albatross numbers plummeted.

These albatrosses don't breed until they at least eight-years-old, only breed every two years, and tend to mate for life. Since the crash, Gibson's albatross numbers have come back slightly, but Antipodean albatross numbers continue to decline.

And adult birds, especially females, are still going missing.

Hooks don't discriminate

Tuna fishing boats use a method called surface longlining to catch their prey. The lines can be up to 100 kilometres long, with thousands of hooks.

Squid is used as bait, a tasty morsel for tuna. Unfortunately, albatrosses agree.

Using satellite tags Graeme and Kath have watched missing albatrosses' paths overlap with those of boats, and in one case, in which leg bands and the satellite tag were returned to them, follow the path of the boat.

Listen as science journalist Rebekah White explores the albatross bycatch problem, and what we could do about it. …

Go to this episode on rnz.co.nz for more details

New Zealand once led the world in marine protection. Now it looks like we will fail to meet our international promise to protect 30 percent of our ocean estate by 2030. Why is stopping fishing so politically fraught? How might our ideas about marine protection need to change? And why, when our seas are in need, is it taking us so long to learn to talk to each other?

This is an updated excerpt from the July - August 2023 New Zealand Geographic feature article 'Taking on water'.

In 1975 five square kilometres from Cape Rodney to Okakari Point was made a marine reserve, the first in New Zealand, and possibly, the world.

"Nothing to do at Goat Island anymore," declared the local newspaper.

Three hundred thousand people now visit every year. And research indicates that this small, protected patch is helping to contribute fish to surrounding areas.

Lunching on experiments

The Marine Reserves Act was created in 1971 in response to campaigning by the late Bill Ballantine, among others. He was director of the University of Auckland's Leigh Marine Laboratory which was established in 1964. But staff and students soon discovered people were eating their experiments.

So that's what the Act was created for: 'the purpose of preserving, as marine reserves for the scientific study of marine life, areas of New Zealand that contain underwater scenery, natural features, or marine life, of such distinctive quality, or so typical, or beautiful, or unique, that their continued preservation is in the national interest.'

Today, with our ocean ecosystems under increasing pressure from commercial and recreational fishing, sedimentation, pollution, and warming, we need our marine protection to do more than preserve small areas for scientific study.

But it's not an easy task. Most marine protection proposals face extensive push back that delays the process for years, sometimes decades.

"It's really, really hard to manage it appropriately," says Professor Chris Hepburn, marine scientist at the University of Otago. "It's land, sea. It's different user groups, it's rights, it's things like the settlement, it's people not understanding each other's points of view."

The act that ignored the Treaty

'The settlement' is the Treaty of Waitangi (Fisheries Claims) Settlement Act 1992, an attempt to restore some of the rights taken from Māori when it comes to fisheries…

Go to this episode on rnz.co.nz for more details

Kuaka bar-tailed godwits make the longest non-stop flights, and researchers are using hi-tech tags to solve the mystery of how and when they sleep.

Godwits hold the record for non-stop long-distance flight - and scientists are wondering when they find time to sleep on the wing.

The long-distance godwit migration

Eastern bar-tailed godwits or kuaka spend up to six months every year in Australasia. At last count, in 2020, the total summer population was estimated at 126,000 birds - 78,000 birds were in New Zealand and the rest in eastern Australia.

After spending the summer feeding on rich intertidal mudflats in the southern hemisphere, the godwits fly north in March. They follow a route known as the East Asian-Australasian Flyway, which takes them to Alaska, via the Yellow Sea. From New Zealand they take seven or eight days to cover the 10,000-or-so kilometres to reach large areas of tidal mudflats in China, Taiwan and Korea. They feed here for four to six weeks, before moving on to the Alaskan tundra, where they breed.

In October they return south, and it is these journeys that have catapulted the godwits into the record books.

Long-haul champions

Godwits make the longest non-stop migration of any bird. We only discovered this when satellite trackers got small enough to be used on them.

In 2007, a female known as E7, set the first record: 11,680 kilometres non-stop. With no breaks for food or rest, she flew for more than eight days, over the open Pacific Ocean, from Alaska to New Zealand.

E7's epic migration has since been eclipsed by the 13,560 kilometre non-stop journey made by bird B6 in 2022. B6 was tagged as a juvenile in Alaska and was just 5 months old when it made its first-ever 11-day flight to Tasmania. Scientists do not know how these young birds find their way to New Zealand and Australia on that first flight - they fly in flocks, and perhaps these flocks include an adult guide?

Sleep in birds

If you've ever taken a long-haul flight from New Zealand you've probably experienced sleep deprivation. Now imagine you're a small bird, flapping your wings continuously, unable to land or feed, on a flight that will take anywhere from 8 to 11 days. When and how do you sleep?

How godwits sleep during their epic flights is the focus of a new research project involving 45 godwits from the Motueka sandspit.

This sleep project involves ornithologist Jesse Conklin, from the United States, and Bart Kempenaers, Mihai Valcu and avian sleep expert Niels Rattenborg, all from the Max Planck Institute for Biological Intelligence, in Germany. …

Go to this episode on rnz.co.nz for more details

The Bounty Islands are tiny in terms of area - just some bits of granite jutting out of the ocean. But they are huge in terms of seabirds. James Frankham joins a team researching the erect-crested penguins who breed in this remote archipelago. Recent counts suggest the penguins of the Bounties are doing fine. But this is not the case on the Antipodes Islands, and the researchers desperately want to know why.

The Bounty Islands jut out of the water like giant granite fins. Steep and sheer, with no greenery in sight. They are covered instead by a mottled white - guano or bird poo from the tens of thousands of penguins and albatrosses that come here to breed.

The least studied penguin

The Bounty Islands is one of two remote, subantarctic island groups home to the erect-crested penguin. Stout and handsome, with bright yellow crests that look like elaborate punk rock hairdos, their remote breeding sites means they've not been studied in depth.

But Dr Thomas Mattern of the Tawaki Project plans to change that.

Good news and bad

Using drones to make photo mosaics of all the Bounty islands, Thomas has counted each penguin breeding pair and arrived at a number that suggests the Bounty Island population of penguins has remained relatively stable since the mid-1990s. Good news.

Not the case for their other breeding sites at the Antipodes Islands, where early evidence suggests a significant decline.

But these island groups are a mere 200 kilometres apart - a hop, skip and a jump in penguin swimming distance. How is one group seemingly doing fine while the other is in trouble?

New Zealand Geographic's James Frankham joins an expedition to these remote and wild islands as the scientists begin to unravel this mystery.

Learn more:

• Read the accompanying New Zealand Geographic article by James Frankham, with photography by Richard Robinson.
• As part of this expedition Claire Concannon also visited the Antipodes Islands to learn how they have fared since mice were eradicated.

Go to this episode on rnz.co.nz for more details

What roles do our ocean ecosystems play in capturing carbon? Kate Evans speaks to iwi Māori working to improve the health of an estuary in the Bay of Plenty, and to scientists studying the fiords of New Zealand's southwest coast. There's potential for huge amounts of carbon to be locked away, if we don't mess it up. 

To avert the worst of the climate crisis we need to reduce our emissions. One way is to phase out fossil fuels, to leave forms of carbon like oil and gas locked up in the ground. But we can also look at ways to lock up more carbon, long term. And some options for this are in our oceans.

The champ of champs

Between 6-10 metres of rain falls in Fiordland each year. An incredible amount. It's part of what powers the forest-to-fiord carbon storage pump that makes Fiordland exceptionally good at locking away large amounts of carbon long-term. Something scientists are only beginning to understand.

Return of the wetland

Luckily, National Park status on land and marine protection in part of the sea have meant that Fiordland has remained relatively untouched.

Not so for some of our other carbon-burying ocean ecosystems. Salt marshes and seagrass meadows in estuaries have taken big hits. But Te Whakapū o Waihī, a collective of local iwi and the Bay of Plenty Regional Council, are fighting back.

Listen as Kate Evans learns about Fiordland's secrets, the plans to restore Waihī wetlands and estuary, and what this all means for our blue carbon potential.

Learn more:

• Read the accompanying New Zealand Geographic article by Kate Evans, with photography by Richard Robinson.
• Alison Ballance previously reported on the work of the Cawthron Institute to collect and grow seagrass seeds.
• Justine Murray joined Professor Kura Paul-Burke out on the Waihī estuary mud flats last year to learn about tohu (signs), nana (seagrass) and tuangi (cockles).
• Parts of the Southern Ocean also acts as a carbon sink, but there are concerns this might change.

Go to this episode on rnz.co.nz for more details

People and livestock gobble so much fish that the seas soon won't keep up. Is the answer to grow fish on land? Kate Evans meets scientists figuring out the puzzles of how to farm some of New Zealand's iconic ocean creatures.

Many of our fisheries are under pressure. At the same time people are eating more fish. Could farming iconic New Zealand species be the future? And what are the advantages of growing fish on land?

A new lease of life

Ocean Beach used to process lambs, a record of 20 000 in one day, but now it's gullies and troughs run with seawater, not blood. Home to the New Zealand Abalone company and Manaaki Whitebait it's become one the frontiers of New Zealand aquaculture - growing fish indoors.

Pāua puzzles and whitebait mysteries

It's not an easy task. Growing fish on land means taking responsibility for their needs throughout their life cycle. First you must identify those needs, account for them in an indoor setting, and make the whole process as efficient as possible so you can still turn a profit. It takes trial and error, and patience.

Learn more:

• Read the accompanying New Zealand Geographic article by Kate Evans, with photography by Richard Robinson.
• Seaweed is also being farmed in a specialised warehouse space in Tauranga.
• Recently the green light has been given for an open ocean salmon farm in the Cook Strait

Go to this episode on rnz.co.nz for more details

Kina numbers are exploding on some of our reefs, decimating seaweed habitats. Could this problem be solved by eating them? Kate Evans investigates the potential of kina-nomics.

The kina are out of control. As many as 40 urchins crowd into a single square metre of rock, devoid of other life.

A kina barren is a symptom of an ecosystem out of balance. Could we eat our way to a solution?

Kina zombies

Kina numbers have exploded as we've eaten too many of their predators - like big snapper and crayfish - that usually keep them in check.

The urchins munch through kelp and seaweed, leaving bare rock and little else. The kina themselves end up suffering too - they persist in these zones as zombies, eating little and barely producing any roe.

Luckily, these barrens can be reversed and kelp forests restored when the kina are removed.

Putting kina on the table

Kina-nomics involves taking starving kina off reefs, fattening them up and selling them to an East Asian market.

But how can the kina be made more consistently tasty? And can economic and conservation goals really align?

Listen to the episode to dive under the water with a kina harvester, taste some kina, and untangle whether a commercial harvest of these spiky taonga can really fix kina barrens.

Learn more:

• Read the accompanying New Zealand Geographic article by Kate Evans, with photography by Richard Robinson.
• Check out another effort to restore kelp forests with the Love Rimurimu project in Wellington, profiled in a recent Our Changing World episode.
• Jesse Mulligan spoke to another researcher studying kina removal in the Marlborough Sounds.

Go to this episode on rnz.co.nz for more details

Crackle, pop, woof, crunch, click. In the ocean, an undersea orchestra is in full swing. Journalist Kate Evans discovers who's playing in it and why, and what happens when human noise drowns out this symphony in the sea.

Symphony in the sea

Journalist Kate Evans and presenter Claire Concannon discover a world of snapping shrimp, singing whales and barking John Dory.

Researchers Professor Craig Radford and Dr Jenni Stanley are uncovering more about the orchestra harmonising under the waves - who's playing in it, and why they are making these sounds.

Plus, what impact is our human noise - like boats - having on ocean creatures?

Learn more:

• Read the accompanying New Zealand Geographic article by Kate Evans, with photography by Richard Robinson.

Go to this episode on rnz.co.nz for more details

A collaboration between Our Changing World and New Zealand Geographic, the Voice of Tangaroa series explores the state of our oceans, and the extraordinary variety of life that calls it home. 

93% of New Zealand is covered in salt water. 80% of our biodiversity is in our seas. And yet this is the part of our realm we understand the least and treat the worst.

A collaboration between Our Changing World and New Zealand Geographic, the Voice of Tangaroa series explores the state of our oceans, and the extraordinary variety of life that calls it home. 

From kina-nomics, to the undersea sound, from growing fish on land, to the debates around our marine reserves - science journalist Kate Evans has been diving into the complexities of how we think about, enjoy, manage and use our oceans, and what this means for the creatures that live in it.

Now, with production help from RNZ's Our Changing World team, and original music composed by Wellington band Grains, you will be able to hear the voices of the characters involved and experience the sounds of our underwater realm.

Voice of Tangaroa is a joint production between RNZ's Our Changing World and New Zealand Geographic.

Reporting for this series is Public Interest Journalism funded through NZ On Air. You can learn more and read the articles for free at www.nzgeo.com/seas

Go to this episode on rnz.co.nz for more details

A group of young New Zealanders and two meteorologists travel to South Georgia Island in the southern Atlantic Ocean to collect weather observations - continuing the scientific legacy of early Antarctic explorers like Shackleton.

Clarification: In this episode there is a discussion about comparing notes about icebergs taken by Shackleton's team aboard the Aurora to that of the current expedition. What this fails to clarify is that the Aurora expedition travelled through the Ross Sea, not the Weddell sea, where ice activity is notably different.

It's home to one of Earth's most spectacular gatherings of wildlife, with millions of penguins, seabirds and seals crowding the shores.

South Georgia, in the far reaches of the Southern Atlantic, is a wild and isolated island. It's also the final resting place of famed Antarctic explorer Ernest Shackleton.

To commemorate the 100th anniversary of Shackleton's last journey, 22 young New Zealanders travelled with the Antarctic Heritage Trust's 9th Inspiring Explorers Expedition to South Georgia.

In the wake of Shackleton

One hundred years ago, Shackleton's untimely death at the age of 47 marked the end of the 'heroic age' of Antarctic exploration. The period left us inspiring stories of courage and survival - as well as an enduring scientific legacy, which continues to be built upon today.

As part of their expedition to South Georgia, the young New Zealanders continued Antarctic explorers' tradition of meticulous data collection, by recording rare weather observations from this remote and seldom-visited destination.

Accompanied by Kelly Davenport and Peter Fisher, two meteorologists from MetService, the Inspiring Explorers science team conducted regular and comprehensive weather reports using the same equipment, terminology and methods that would have been used in Shackleton's time. But they also brought some state-of-the art weather equipment, which can collect more data than a heroic-era meteorologist could ever have dreamed of.

Lots of data is important for weather and climate science today. Data feeds into global weather models - complex simulations of the planet's atmosphere that assist the near-term prediction of weather patterns worldwide. Data collected from remote locations such as South Georgia is particularly impactful, as it helps us fill in the blanks in the map of Earth's weather.

South Georgia: A barometer for change? …

Go to this episode on rnz.co.nz for more details

An ambitious project to rid the remote Antipodes Island of introduced mice proved successful in 2018. Claire Concannon visits the spectacular subantarctic island to meet the locals - from penguins to megaherbs - and the people studying the wildlife. Plus, we learn about what's at stake in the next island eradication challenge for New Zealand.

Excitement rises on board the expedition yacht Evohe as the largest of the Antipodes Islands appears out of the mist.

These subantarctic islands are wild and remote - some 860km southeast of Rakiura Stewart Island. Their isolation, in a far-flung corner of the South Pacific, means they're some of the most untouched islands in the world.

They're also brimming with wildlife.

A wildlife hotspot

Department of Conservation rangers Jemma Welch and Erin Patterson will soon be landing to meet some of the wildlife and start their task: a whole-island count of the Antipodean albatross. Erin dreams of romping through megaherbs, while Jemma, a self-confessed seabird nerd will be in her element - 21 seabird species breed here.

It's an incredible landscape. Tussock growing in pillars up to two metres tall, pipits and snipe and parakeets roaming, albatrosses and petrels floating overhead, fur seals and elephant seal pups hauled up in the rocky coves.

With great biodiversity comes great responsibility

The Antipodes Islands, like the other subantarctic islands, have their own cultural and social history, alongside their incredible natural history.

In the early 1800s gangs of sealers decimated the fur seal population on these islands. Along the way mice were introduced. Remarkably - and fortunately - rats never established.

But the mice were enough to have a major impact. Their population swelled to huge numbers (an estimated 200,000 across the 21 km2 island). This multitude of mice munched their way through a large portion of the native invertebrates on the island - many of which are endemic, meaning they're not found anywhere else.

This drop in invertebrates had a knock-on effect: it reduced the amount of food available for insect-loving birds like the pipit and snipe. The mice themselves also disrupted burrowing seabirds. And there was another fear of what might be to come as gruesome footage emerged from other islands where mice had developed the disturbing behaviour of eating live albatross chicks as they sat on the nest. …

Go to this episode on rnz.co.nz for more details

How fast - and how completely - could Antarctica's smaller western ice sheet melt in a warming world? An international science team, led by Aotearoa New Zealand, set out to investigate whether two degrees of warming could already be a tipping point for the frozen continent.

Antarctica is losing ice at an accelerating rate, particularly in some parts of West Antarctica.

How did the small and more vulnerable West Antarctic Ice Sheet behave during past periods of natural warming? Geological evidence is sparse, but an ambitious sediment-drilling project aims to change that.

Drilling back in time to explore past periods of warming

SWAIS2C - short for Sensitivity of the West Antarctic Ice Sheet to 2°C - is an international collaboration, co-led by Aotearoa New Zealand. During its first season this summer, the team set up camp close to the grounding line of the Ross Ice Shelf, where the world's largest slab of floating ice is at its thickest. Below more than 580 metres of ice, only about 50 metres of ocean separate the bottom of the ice from the ocean floor.

The team used hot water to thaw a hole through the ice to reach the seafloor where layers of mud and rock have been accumulating for millennia, building up one of Earth's memory banks of environmental conditions at the time they were deposited.

Saving the world's largest ice shelf

The SWAIS2C team successfully retrieved the longest sediment core ever extracted from the remote Siple Coast, which holds clues about the ice sheet's more recent past. Next season, the team hopes to drill deeper and further back in time to the last interglacial period, some 125,000 years ago, when Earth was around 1.5°C warmer than pre-industrial temperatures - similar to the warming we are approaching now.

The goal is to track whether the grounding line of the Ross Ice Shelf retreated or advanced during this and even earlier periods of natural warming, and what that tells us about the risk of the West Antarctic Ice Sheet breaking up partly, or even completely, in the future.

If the floating Ross Ice Shelf were to melt, it would have no impact on sea levels. But the ice shelf acts as a buttress, holding the West Antarctic Ice Sheet in place. If the shelf goes, the ice sheet would likely follow - and the consequence could be 3-5 metres of sea level rise. …

Go to this episode on rnz.co.nz for more details

Allergenic pollen is a big trigger for New Zealand's high rates of hay fever and asthma. But for 35 years, we've had no current data on pollen levels. Until now. Justin Gregory talks to a team who want to change that.

The view is what you notice first.

It's takes time to get up to the roof of the Auckland War Memorial Museum Tamaki Paenga Hera but once you're there, it's worth it. A 360-degree turn takes in all the major sights of central Auckland. If you weren't looking for it, you might not notice a green, medium-sized metal device placed just so to catch the breeze. This device, a clockwork volumetric spore trap, is the key to learning more about pollen levels in this country - a major cause of asthma and hay fever.

New Zealand's first pollen trap in 35 years

Asthma affects approximately one in eight adults and one in five children in New Zealand, with rates higher than those in Australia or the UK. Yet, for the past three decades, the country has operated without a single pollen trap - until now.

Associate professors Stuti Misra and Amy Chan from the University of Auckland co-lead a team operating the country's first pollen trap in 35 years. Since July 2023, the team has been trapping pollen and spores, identifying and counting them. Their mission is to update the data on New Zealand's pollen and understand its correlation with the country's soaring asthma and allergy rates.

Climate change sends pollen rates soaring

Their research is funded for just a year, but good data is already emerging about seasonal variations in pollen. The team already know the number of high pollen count days has increased by 75 percent over the last 30 years, likely due to climate change. This increase not only signifies an earlier onset of the grass season but also a higher volume of pollen in the air - posing a greater threat to those with respiratory issues.

Amy is running a related clinical trial, developing real-time prediction tools and smart devices to avoid asthma attacks. Using individualised data like sleep patterns, breathing rate, weather information, medication use and weather, she hopes to determine what information can most accurately predict an attack and develop tools to warn sufferers.

Listen to the episode to learn more about why pollen levels are rising, what technology is emerging to measure those levels and how smart phones and watches could be key to managing and preventing asthma attacks. …

Go to this episode on rnz.co.nz for more details

Giant kelp is disappearing from Wellington Harbour. Love Rimurimu is aiming to restore lush underwater kelp forests with an ambitious and collaborative replanting effort. Claire Concannon dives in to the wonderful world of seaweeds.

The aquarium room at NIWA is awash with sound. A pump system hums, clicks and splashes as it circulates water through large tanks like the Wellington bucket fountain.

Inside, tiny seaweed fronds tied onto rocks dance in the currents.

Growing kelp

These fronds might be small - a few centimetres at most - but they can grow into lush forests. Giant kelp (Macrocystis pyrifera) starts out in a lab as microscopic spores, before it is coaxed through each phase of its life cycle by staff from the Love Rimurimu project and phycologist Dr Roberta D'Archino.

After growing a few more centimetres, the kelp will be returned to the wild, part of an ambitious effort to restore the seaweed ecosystems of Wellington harbour.

Love Rimurimu

Love Rimurimu began as an educational programme delivered by Mountains to Sea Wellington, says project lead Zoe Studd. Local rangatahi were encouraged to learn more about seaweed, to get into the ocean and have a look around, and to learn about why kelp was disappearing.

But when students from Kura Kaupapa Māori o Ngā Mokopuna suggested that they should be actively growing kelp to plant back out, Love Rimurimu took on a new direction.

Now, the project is piloting plant-outs to help regenerate the giant kelp forests that are so vital to a healthy underwater ecosystem, working with Taranaki Wānui ki Te Upoko o Te Ika, NIWA, Victoria University of Wellington, the kura, and the local community.

Listen to the episode to learn about the stressors impacting kelp, to hear how giant kelp is grown in a lab, and to meet some of the Love Rimurimu team who have been planting out kelp in their blue backyard. …

Go to this episode on rnz.co.nz for more details

In the final instalment of the summer science series, science communication students tackle two controversial topics: medicinal cannabis, and AI consciousness.

In our final instalment of the summer science series, we have two more stories from science communication students.

Each year, science communication students at the University of Otago's Department of Science Communication are tasked with producing a podcast on a controversial science topic.

In this episode, we hear two of those stories - on artificial intelligence and medicinal cannabis - from Marika Ljunberg and Rhys Latton.

The engineer and the ghost

In June 2022, Blake Lemoine, a software engineer at Google's Responsible AI division, decided to go public. For a period of time, he had been talking to his executives about his firm belief that the chatbot they were developing, LaMDA, had gained consciousness. But Lemoine's executives were convinced he was mistaken.

How can we know whether an artificial system is conscious? What should we do if we realise we have created artificial conscious entities? And should we try and create them at all?

According to neuroethicist Dr Michele Farisco, conscious AI is the only way we can make sure that AI is developed safely: by giving it a moral sensibility. But not everyone agrees that this is a good idea.

Listen to the episode to learn more about ethics and artificial consciousness, and explore the question: what's humane for the non-human?

Music credits:

• Contemporary New Age Theme 9 by Mac Squier (BMI) CAE/IPI#420010737, publisher Mac Squier Music (BMI)
• Busy by Lenny Williams (BMI) CAE/IPI#195221668, publisher Harry L. Williams Music Publishing (BMI)
• Background Info by Lenny Williams (BMI) CAE/IPI#195221668, publisher Harry L. Williams Music Publishing (BMI)
• Clock Mallets by Lenny Williams (BMI) CAE/IPI#195221668, publisher Harry L. Williams Music Publishing (BMI)
• Gentle Harp Underscore by Lenny Williams (BMI) CAE/IPI#195221668, publisher Harry L. Williams Music Publishing (BMI)

Medicinal cannabis: the hazy world of evidence and efficacy

Medicinal cannabis is a now legally available treatment option in Aotearoa through your GP, but many doctors are hesitant to prescribe it due to a lack of solid evidence of its efficacy.

One of the reasons cannabis is controversial is that there is no single condition where cannabis is the preferred, first-line treatment option, says Dr Peter Radue from the Department of General Practice and Rural Health at the University of Otago. …

Go to this episode on rnz.co.nz for more details

Should we intervene to prevent hybridisation between an endangered species and its common relative? In this week's summer science episode, two students from the Department of Science Communication at the University of Otago tell stories of science controversy: the conservation conundrum of hybrids, and the relationship between western science and mātauranga Māori.

Each year, science communication students at the University of Otago's Department of Science Communication are tasked with producing a podcast on a controversial science topic. In this episode, we hear two of those stories - on the issue of hybrids in conservation, and on mātauranga Māori - from Janice Huang and Jodie Evans.

How should we manage hybrid species in New Zealand?

Hybridisation is the mixing of genes from different species or subspecies. Throughout history, humans have harnessed this powerful force to create desired crops and domesticated animals.

But in the field of wildlife conservation, hybridisation can threaten some species with extinction.

In New Zealand, one example is the kakī or black stilt, a nationally critical, all-black wader bird that lives in the braided rivers of the Mackenzie basin. Kakī can hybridise with their closest relative, the poaka or pied stilt.

The kakī population, numbering around 156 wild adult birds, is closely managed to prevent hybridisation.

Listen to the episode to hear contrasting opinions on the plight of the kakī and other organisms threatened by hybridisation.

In defence of mana: Mātauranga Māori and science

Mātauranga Māori translates to Māori knowledge. It's a system that evolved before European contact as Māori encountered new climates, geography, flora and fauna in Aotearoa.

Over the past few years its comparison to western science has ignited significant controversy within the scientific community. The debate came to a peak in 2021 when seven University of Auckland professors signed an open letter to the Listener opposing the integration of mātauranga Māori with secondary school science.

Fostering mātauranga Māori is not about replacing science, says Professor Georgina Stewart, who studies the relationships between science, education language and knowledge.

Increasing mana (respect) for the subjects of research - materials, beings or places - will improve Aotearoa's science with better outcomes for all scientists, says Gemella Reynolds-Hatem, a wāhine Māori student who is passionate about her whakapapa and the value it brings to her study.

Listen to the episode to hear Georgina's expert commentary and the lived experiences of Gemella as she navigates academia…

Go to this episode on rnz.co.nz for more details

Kākā numbers are skyrocketing in Te Whanganui-a-Tara Wellington thanks to conservation efforts. The summer science series continues with a walk through Zealandia to find out why you shouldn't feed these inquisitive parrots.

Our summer science series continues with a story from Samantha Lloyd-Evans, a student from the Centre for Science in Society at Victoria University of Wellington.

Samantha takes us for a walk in Te Whanganui-a-Tara Wellington, where kākā numbers have skyrocketed in recent years, thanks to conservation efforts.

This increase in kākā has led to an increase in human-kākā interactions, as people learn how to live with these large endemic parrots.

For the most part, encounters with these inquisitive birds are positive. But seemingly helpful actions such as feeding kākā can have unintended consequences, says Ellen Irwin, lead conservation ranger at Zealandia Ecosanctuary.

Why feeding kākā is a bad idea

Wellingtonians feeding kākā in their backyards can cause a nutrient imbalance in the diet of kākā chicks, Ellen explains. This can lead to metabolic bone disease and other complications, and the chicks often die in the nest.

There are other risks to bird feeding as well, such as attracting pests or accidentally giving the kākā too many calories, similar to getting a toddler hyped up on sugar.

These risks are why Zealandia and other conservation groups are pushing to educate locals on how to safely interact with native wildlife.

Planting natives in your garden, practising responsible pet ownership, and joining your local trapping group are actions you can take to help native birds like kākā. Ellen also encourages the use of apps like iNaturalist to keep track of the birds seen in Wellington.

Join Ellen for a stroll through the lush ngahere forest of Zealandia while discussing Wellington's booming kākā population and how you can help them.

Learn more:

• Kākā have also made a comeback in Õtepoti Dunedin thanks to Orokonui Ecosanctuary.
• In Wellington, it's not just kākā too: urban bush birds are doing well in the capital, Alison Ballance reported in this 2018 episode.
• Meet some of the non-bird residents at Zealandia Ecosanctuary with Claire Concannon in this episode from May 2023.

Go to this episode on rnz.co.nz for more details

The summer science fun continues with an episode from RNZ podcast Voices. Meet Gaia Dell'Arriccia, a scientist originally from the south of France who studies the seabirds that live around Auckland's coastlines.

A seabird colony at night is a noisy place. But it's also an incredible experience to have thousands of birds flying around you, says seabird scientist Gaia Dell'Arriccia.

The summer science series continues this week with an episode from Voices, an RNZ podcast that tells the stories of the one-quarter of New Zealanders born overseas.

Host Kadambari Raghukumar meets Gaia at the Ōrākei Basin, where she is monitoring a shag breeding colony.

Listen to hear about Gaia's work studying the seabirds around the Auckland coast and offshore islands, and her journey from the Mediterranean to Aotearoa.

Learn more:

• Scientists are also studying the feathers of museum specimens to figure out how Auckland's seabird populations are changing: What feathers can tell us about the past lives of seabirds.
• Meet another passionate seabird scientist, Edin Whitehead, in For the love of seabirds.
• Visit one of Auckland's seabird hotspots in our two-part episode on the Noises Islands: Part 1 and Part 2.
• Head out onto the streets of Auckland with the petrel patrol in search of crash-landed seabirds.

Go to this episode on rnz.co.nz for more details

The summer science series kicks off with an episode from award-winning podcast Black Sheep, about a backyard inventor called Victor Penny who sparked sensational headlines about death ray inventions in 1935.

In 1935, a series of extraordinary newspaper articles claimed a backyard inventor called Victor Penny was trying to build a death ray for the New Zealand government.

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Welcome to the summer science series from Our Changing World. We're kicking off the holiday season with a science-themed episode from award-winning history podcast Black Sheep.

Victor Penny was a self-taught engineer and inventor who worked with early radio technology - and at a secret government laboratory on Matiu/Somes Island.

Listen to find out the truth - and the science - behind the sensational 'death ray' headlines.

Learn more:

Hear the story of the first radio broadcast in New Zealand in 100 years of radio and the spectrum of light.

Listen to more Black Sheep episodes.

Go to this episode on rnz.co.nz for more details

This week on Our Changing World RNZ podcast producer, and occasional dinosaur correspondent William Ray visits Ngā Taniwha o Rūpapa Dinosaurs of Patagonia, a special exhibition at Te Papa Museum to discover the surprising link between the giant dinosaurs of Patagonia, and prehistoric New Zealand.

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This week on Our Changing World, RNZ podcast producer and occasional dinosaur correspondent William Ray visits Ngā Taniwha o Rūpapa Dinosaurs of Patagonia, a special exhibition at Te Papa Museum, to discover the surprising link between the giant dinosaurs of Patagonia and prehistoric New Zealand.

An ancient giant of Patagonia

One hundred and one million years ago, an astonishingly large animal breathed its last breath on a muddy riverbank in what would eventually become Patagonia in Argentina.

We don't know exactly how it died. Possibly it just got stuck in the mud, a potentially fatal prospect for an animal that weighed as much as eight African elephants.

Its 2.4-metre-long, 600-kilogram femur was eventually unearthed by an Argentinian farm worker, and later inspected by paleontologists from Argentina's Museo Paleontológico Egidio Feruglio. The femur was identified as belonging to a massive long-necked sauropod dinosaur dubbed Patagotitan mayorum, which ranks among the largest animals to ever live on land.

Our Changing World producer William Ray discovers the story of how these enormous animals evolved - and their surprising link to Aotearoa New Zealand.

Special thanks to Te Papa Museum and the Department of Conservation for the soundscape in this episode.

Learn more:

Earlier this year, William reported the story behind another dinosaur exhibit: a pair of Tyrannosaurus rex fossils at Auckland Museum.

For more fossils of ancient giants, check out our episode about the huge penguins that once roamed Aotearoa.

Go to this episode on rnz.co.nz for more details

Off the coast of New Zealand, deep underwater, the seafloor shifts in landslides and slow-motion earthquakes. Claire Concannon meets two researchers investigating geological phenomena that could pose a tsunami risk to Aotearoa New Zealand.

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Underwater landslides: out of sight, but not out of mind

One million years ago something triggered an underwater landslide in the Tasman Sea off the coast of Taranaki. A massive amount of sediment, 32 times the volume of Mount Ruapehu, thundered down a slope.

But if the land slides underwater and there's nobody there to see it, does it have an impact?

Early modelling suggests yes - it's likely to have caused a large tsunami that would have hit the west coast of Aotearoa.

So today, with our populated coastlines and our underwater communication cables, what's the likelihood of it happening again?

That's what GNS senior marine geohazard researcher Dr Suzanne Bull is keen to answer.

Figuring out the where and why

Just like on land, any sloped area under the sea has the potential to slide - but underwater landslides tend to be far more massive.

Understanding what triggers them is tricky, says Suzanne, because you can't easily survey after an event.

For example, in the aftermath of Cyclone Gabrielle more than 140,000 landslides have been documented from on-the-ground reports and aerial imagery, but doing a similar assessment underwater is far more expensive and time consuming.

Earthquakes could be another potential trigger. One natural disaster that woke scientists up to the potential hazard of such landslides was when a 7.0 magnitude earthquake off Papua New Guinea in 1998 resulted in an unexpected tsunami. Investigations indicated that it was caused not by the earthquake itself, but by a large underwater landslide.

Listen to the episode to hear Suzanne explain how she and her colleagues have been investigating a group of large landslides in the Tasman Sea in the hopes of learning more about the potential risks to Aotearoa.

Homing in on the zone

Of course, Aoteaoroa is also at risk from tsunamis generated in the more 'classic' way: large earthquakes occurring underwater.

Off the North Island's East Coast, the Pacific Plate dives under the Australian Plate in an area known as the Hikurangi subduction zone.

Such subduction zones have been responsible for extremely large earthquakes around the Pacific Ring of Fire, says GNS scientist Dr Stuart Henrys, so he and others are keen to understand the Hikurangi area in as much detail as possible. …

Go to this episode on rnz.co.nz for more details

Go behind the scenes at the National Geohazard Monitoring Centre, where a team of analysts are on alert 24/7 for earthquakes, volcanic activity, tsunamis and landslides. What happens when a natural disaster strikes?

It could be the headquarters for a rocket launch, or the control centre for a highly coordinated operation. One wall is full of large monitors, information updating in real time. Cameras, maps of the Pacific, incoming streams of data. A room that never sleeps, that's always on alert.

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24/7 operation

This is the National Geohazard Monitoring Centre (NGMC). Based at GNS Science in Lower Hutt in Wellington, it's part of GeoNet - the programme tasked with New Zealand's geohazard monitoring and response, operated in partnership with Toka Tū Ake EQC, Toitū Te Whenua Land Information New Zealand and GNS Science

Kimberly Presow has worked here for five years, since this new 24/7 version of the centre opened in 2018. She's a shift leader now, responsible for one of the teams of geohazard analysts that constantly scan the monitors for any changes that might indicate a significant geohazard event.

Four main geohazards

While keeping an eye out for earthquakes is the bread and butter of the NGMC, they are also on alert for three other geohazards: landslides, tsunamis and volcanic activity. A network of seismometers, underwater pressure sensors, coastal gauges, cameras and international monitoring stations constantly feed data into this room, where the geohazard analysts are wary to any changes in the patterns.

A pager will sound for anything greater than a magnitude six earthquake, but the geohazard analysts will be on alert for any change they see in the incoming data. And once something is identified, they will work quickly to assess and update the information, sometimes correcting errors in the automatic system - which may, for example, see one earthquake when there were two.

Coordinating the response

When a large event occurs the NGMC goes into response mode.

The analysts alert civil defence, and the on-call duty scientist will be looped in to give their assessment. From there, depending on the scale of the hazard, an entire panel of expert scientists might be assembled. In the meantime, the incoming data is being constantly assessed and updated, to fine-tune the information about the location, scale and repercussions of the event, to further inform civil defence. …

Go to this episode on rnz.co.nz for more details

Mohua are bright yellow forest birds - but despite their eye-catching plumage, they can be tricky to spot flitting high in the forest canopy. Claire Concannon visits the Makarora mohua population, where a team of conservationists and scientists are testing acoustic machine learning to identify individual birds.

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A 'rat plague' has come to the beech forest near Makarora, and Jo Tilson is worried for the little population of mohua who call this area home.

The 'bush canary'

In the 1800s mohua were one of the most abundant forest birds, found in different forest types. Their bright yellow heads (hence their common English name, yellowhead) and yellow-feathered bellies led them to being dubbed the 'bush canary' by European settlers.

But - and you know this story - forest clearance and introduced predators reduced their population and range significantly. These little songbird insectivores nest in holes in trees, and so are vulnerable to stoats and ship rats. Some mohua have been transferred to predator-free offshore islands where they are doing well, but on mainland New Zealand there remains just a few small, scattered populations living in South Island beech forest.

One of these can be found just north of Makarora, near Cameron Flat, in the silver beech forest that lines the west side of the Makarora River as it runs alongside State Highway 6 through the Haast Pass.

It takes a village

Jo works as a biodiversity coordinator for Southern Lakes Sanctuary, focused on species and predator monitoring for the Mātukituki and Makarora hubs. Southern Lakes Sanctuary is essentially an umbrella organisation that has wrapped around existing conservation groups to enable a regionwide effort.

In this area, that includes a highly motivated group of 60 or so trapping volunteers from the Central Otago Lakes Branch of Forest & Bird. With the first trap lines established in 1998, the group has been "sustainably harvesting predators," as volunteer Mo Turnbull puts it, for more than 25 years, to help the local mohua population hold on.

But it's not about dead rats, Mo says, it's about live mohua. So how are they doing?

Cryptic in the canopy

Transects run by the Department of Conservation and the sanctuary across the years indicate that the mohua numbers in the area are declining. But without a complete census it's hard to have the full picture of what's going on. …

Go to this episode on rnz.co.nz for more details

Varroa mite parasites cause major problems for honey bees - and beekeepers. Now, New Zealand researchers are investigating a new type of RNA-based treatment that could make treating varroa mite infestations easier, as well as better for the bees and the environment.

Varroa destructor mites are bad news for honey bees.

Not only do they attack the bees by chewing on a vital organ called the fat body, but they also introduce problematic viruses to the hive - such as deformed wing virus, which does exactly what it says on the tin.

Beekeepers worldwide must treat for varroa mites several times a year just to keep their numbers in check. They mostly use pesticides, which can have damaging effects on the bees and environment. The mites are also beginning to develop resistance to pesticides, but a new treatment method may be just on the horizon.

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RNA interference

This is what PhD candidates Zoe Smeele and Rose McGruddy have been researching. Under the supervision of Professor Phil Lester, they've been working with US biotechnology company Greenlight Biosciences to investigate how their new treatment for varroa mites works.

The treatment is based on a technique called RNA interference. An interesting bio-hack that researchers have figured out is how they turn a natural virus defence mechanism in the cell against one of the mite's vital proteins.

Greenlight Biosciences were able to identify a working treatment that reduced mite numbers in field trials in the states but turned to the New Zealand researchers for help in uncovering exactly how it works.

Mini-hive experiments

In one of the research labs in the School of Biological Sciences at Te Herenga Waka Victoria University of Wellington, Zoe and Rose have been conducting mini-hive experiments. Their participants are larval stage bees taken from the hives on the roof of the building, infected with varroa mites.

The nurse bees that feed the larvae are given plastic pouches full of sugar water with the RNA interference treatment inside. What the team has discovered is that instead of killing the mites, what the treatment does is severely impact the mites' reproduction.

But what about real beehives?

Initial field trials with New Zealand beekeepers have showed some promise, but also highlighted that there's much to learn in terms of the dosage per bee. A next round of trials is just getting underway, and this will also include RFID tagging of bees to monitor any impacts at the individual bee level. …

Go to this episode on rnz.co.nz for more details

New video series: A turning point in the fight to preserve Aotearoa's natural environment.

If you enjoy listening to Our Changing World, we reckon that you might be keen on a new video series just released on RNZ.

The Turning Point is about the new generation of kaitiaki across Aotearoa taking on the challenge of protecting and restoring our natural environment, paving the way to a more hopeful future.

Each of the six episodes follows one person, giving a glimpse into the communities they work with and telling the story of their journey into conservation. They look at how they got to where they are now, what their day-to-day jobs look like, the challenges facing the affected species and the impact of their work.

Caring for penguins, growing native plants, battling wilding pines, protecting kōkako, helping migratory fish and bridging the gap between science and mātauranga Māori - these young conservationists are making a positive change for te taiao.

Watch the The Turning Point on the RNZ website, or on the RNZ YouTube channel.

To learn more:

The Turning Point focuses on conservation roles funded under the Covid-19 Jobs for Nature fund. Our Changing World has told several stories of projects also supported by this fund - such as creating a home for inanga outside Hokitika and replanting near Pūnakaiki.

Go to this episode on rnz.co.nz for more details

Claire Concannon meets GERALDINE, the Gigantic and Extremely Radical Atmosphere-Lacking Device for Interesting and Novel Experimentation. Plus, a team of scientists and engineers designing plasma rocket thrusters for space travel with super-conducting magnets.

GERALDINE loiters at one end of the giant lab space. Metal, shiny, round and very large, she's been purposely built to help scientists and engineers test plasma rocket thrusters in the vacuum environment of space.

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New frontiers

As senior scientist Dr Ben Mallett explains, GERALDINE's full name is the Gigantic and Extremely Radical Atmosphere-Lacking Device for Interesting and Novel Experimentation. And you can't really get more novel than the current project he is working on. It's the Paihau - Robinson Research Institute's first foray into space, and they are looking to test a brand-new superconducting magnet and flux pump design to see if it can make the plasma rockets more efficient.

Plasma rockets

Actually, the full and correct name is 'applied-field magneto plasma dynamic thrusters'. These kinds of rockets don't produce a huge amount of force - for some, the thrust they produce is equal to the weight of a piece of paper on your hand. However, they are extremely efficient. In the frictionless vacuum of space, over time, they can help spacecrafts build up great speeds and travel long distances.

Plasma is charged gas, and in these kinds of electric space thruster, electromagnets are used to direct the plasma so that it fires out the back and pushes the rocket forward. But the weight and power requirements of current magnets used in these thrusters is a barrier.

Enter Paihau - Robinson, known for their work with high-temperature superconducting magnets. Superconducting materials conduct electrical current with no resistance, so they can create very powerful electro-magnets when a current is passed through them. They do come with baggage though - a cryocooler to keep the magnet at -200oC and a flux pump to send current through the magnet to power it up. All of these parts need to be carefully designed and then tested.

But space is tricky....

There's a lot to think about when making equipment to be used in space. There's the shaking of everything as it gets launched through the atmosphere and then there's the lack of atmosphere once it's up there - the vacuum, the radiation, the different temperature effects - all have to be considered. …

Go to this episode on rnz.co.nz for more details

A Moriori musician, an ethnomusicologist and the Hokotehi Moriori Trust are part of a team helping to revitalise Moriori culture with 3D-printed replicas of traditional bone flutes from Rēkohu the Chatham Islands. Claire Concannon finds out more about the Moriori, music and manawa project.

A born and bred Chatham Islander, from the largest island, Rēkohu, musician Ajay Peni says the wildness, the ocean, the ruralness all feeds into his music. Through his nan's side Ajay can trace his hokopapa, his genealogy, back to indigenous Moriori who first settled these islands.

Today he is playing his part in the revitalisation of Moriori culture, by bringing traditional Moriori songs, rongo, into contemporary times.

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Rongo

Through collaboration with the Hokotehi Moriori Trust Ajay has already been part of the creation of two collections of rongo - Hokotehi Me Rongo - featuring Ta Rē Moriori lyrics long ago recorded by Alexander Shand and Hirawanu Tapu.

He is currently working on another collection of rongo with the Trust, and alongside this, creating music for the Moriori, music and manawa project based at the University of Otago, with fellow musician Alistair Fraser.

Two remaining Moriori bone flutes

Dr Jennifer Cattermole is one of the co-leads of this project. An ethnomusicologist, she studies music in its social and cultural contexts. After scouring different sources of information, two remaining Moriori bone flutes were identified: one in the Canterbury Museum in Christchurch, the other in the Bishop Museum in Hawai'i.

But careful preservation of these mīheke oro (treasured musical instruments) in museums means that no one can touch them with their hands or play them. So how can they be used as part of the Moriori cultural revitalisation that has been happening for many years now?

Enter modern technology.

Careful CT scanning the two flutes meant that the tiny, nuanced details of their carving could be captured in digital form, and then translated into a 3D print design. As well as allowing experimentation of different materials to recreate the look, feel and sound of the flutes, the 3D-printed versions were used to guide a carving wānanga, where copies of the flute were made from what was likely the original material - albatross or hopo bone.

Multi-sensory exhibition …

Go to this episode on rnz.co.nz for more details

In the last week, Hurricane Otis hit southern Mexico with little warning, and Cyclone Lola set a record for the earliest category five cyclone in the southern hemisphere. Climate change is making work tricky for weather forecasters. What might be in store for our upcoming El Niño summer?

Last week in southern Mexico Hurricane Otis made landfall near the city of Acapulco as a category five hurricane. With wind speeds estimated at around 266 kph (165 mph) it caused huge amounts of damage and loss of life.

In part because there was so little warning.

Just 24 hours beforehand the US National Hurricane Centre modelling of then tropical storm Otis predicted max winds of about 112 kph (70 mph).

But the rapid and unexpected intensification of Otis caught everyone off guard, including the weather models.

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Is the forecasting game changing?

"You can never really attribute, you know, one single weather event to climate change. It's very difficult to do that," says NIWA meteorologist Tristan Meyers. But, he says, different recent extreme weather events in New Zealand do have the "fingerprints of climate change" all over them.

As part of his job, Tristan works on a number of different forecasts: from on demand 'now-casts' to look a few hours ahead - maybe to help Fire and Emergency New Zealand deal with spreading fires - through to seasonal forecasts across a few months to help those dependent on the weather for their livelihoods prepare for what's to come.

But the impacts of climate change are making his job trickier.

El Niño is here

There's a large patch of ocean in the Eastern Pacific along the equator where sea surface temperatures are monitored closely. Think of it as extending out from Ecuador in South America, into the middle of the Pacific.

When this patch of ocean is warmer than normal, and the air above the ocean responds, that's when the El Niño Southern Oscillation is in effect. Wind and ocean currents change, and when these changes spread out across the Pacific, it generally means more westerly winds for Aotearoa.

With El Niño officially declared as an important climate driver for this summer season, we can look at past seasons to forecast what might be coming: westerly winds that bring rain to the west coast but a drier outlook for the east of the country.

Overlapping climate drivers …

Go to this episode on rnz.co.nz for more details

Could your burger one day come with a plankton patty? Alison Ballance visits the Cawthron Institute's collection of more than 750 different strains of microalgae, where scientists are investigating these teeny organisms for new food ingredients and powerful painkillers.

Imagine a future where your burger comes with a plankton patty.

Or where you are prepped for a hospital operation with an algal anaesthetic.

If Cawthron Institute researchers have their way, this microalgae-themed future for food and pharmaceuticals could be just around the corner.

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The Cawthron Institute research is based on a culture collection of microalgae, also known as phytoplankton. The collection goes back more than three decades, and now contains more than 750 isolates or different strains of microalgae, collected from New Zealand, Antarctica and the Pacific. It includes marine and freshwater species.

The collection differs from Aotearoa's other significant national biological collections - think herbariums containing dried specimens of plants, for example - in that it is a living collection.

Curator Sarah Challenger has the job of keeping the collection alive and healthy. The microalgae require light of the right wavelengths, nutrients, and a suitable temperature to survive. Every three weeks Sarah carefully replaces the water and nutrients in the small plastic pottles in which the living samples are maintained.

Sarah says it is a much easier job to care for some of the freshwater microalgae, which can survive cryopreservation - or freezing - to very low temperatures and be brought back to life later as needed.

The Cawthron Institute's Chief Science Officer, Dr Cath McLeod, says the collection began with a monitoring programme for toxic phytoplankton blooms in the Marlborough Sounds that were having an impact on shellfish farms. The collection grew as the researchers realised that phytoplankton was a vast untapped resource which could potentially provide ingredients for food and pharmaceutical products.

Developing new food and drugs

Andy Selwood and Dr Matt Miller are currently screening about a hundred of the different strains to identify which ones might produce useful bioactive compounds. They grow each strain in a series of one-litre bioreactors, exposed to slightly different combinations of light and nutrients. This allows the researchers to identify optimum growth conditions and work out which strains are producing what kinds of bioactives and in what quantities. …

Go to this episode on rnz.co.nz for more details

In the ever-shifting streams and channels of a braided river, creatures must adapt to change. Claire Concannon joins a researcher on the spectacular Cass River near Tekapo for a spot of electrofishing and bird counting - part of a project seeking to understand this complex ecosystem and the threats it faces.

It's a blue-sky spring day in the Canterbury high country. The sun beams and the wind is whipping down the wide gravel plains of the braided Cass River.

To the left is the Gamack Range. To the right, the vivid turquoise of Lake Tekapo. Black-fronted terns call out as they drift above the weaving and winding water channels, on the hunt for fish to deliver as gifts as part of their courtship.

And standing in the middle of one of the streams, water up to her knees and a heart-shaped metal wand stuck into the fast-flowing water, is University of Canterbury PhD candidate Holly Harris. She is electrofishing.

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Changing channels

Braided rivers are rare worldwide. In New Zealand they are classed as naturally rare habitats, but we are lucky in comparison to other countries. There are a few in the south of the North Island, but most can be found in Te Waipounamu.

If you've flown over the South Island you'll have seen them in all their glory - silver snaking braids of water in wide gravel floodplains making their way from the Southern Alps to the ocean.

They are complex and dynamic ecosystems. There are springs that feed side streams, and water can flow through the gravel under the surface to pop up in other places. As the seasons change, floods wash out main braids and give life to side braids. The gravel shifts and the channels can change course. It's an intricate dance that the creatures that live here have learned to adapt to.

Life and death

As in every ecosystem, in braided rivers there is an interconnected web of things eating other things. The freshwater invertebrates eat the algae that grows on settled river stones. The fish eat the invertebrates. The birds eat the fish, lizards and terrestrial invertebrates.

As part of Holly's PhD she wants to better understand the elaborate interplay between life in the river: how it is interconnected, and how it can move and adapt to the changing channels. She uses isotopic analysis of different species to investigate this. …

Go to this episode on rnz.co.nz for more details

Giant penguins weighing up to 150 kilograms once roamed the waters around New Zealand. Claire Concannon speaks to a palaeontologist and learns about penguin evolution, extinct species that dwarfed today's emperors, and why Aotearoa is such a great place to study these birds that 'fly' through the water.

Evolution spins out some crazy designs.

Bats that can hunt in the dark using echolocation, spiders that use water surface tension to detect prey, and rugby-ball-shaped birds who look like they are wearing formal attire as they dive through the water to hunt.

Marching penguins, dancing penguins, surfing penguins. These birds have found their niche in both the oceans, and on our movie screens.

What made penguins the beloved birds that they are today?

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From flying in air, to flying in water

Our story begins 62 million years ago. "I recognise that that's just a number," says Dr Daniel Thomas, of Massey University. "But to put that into context - at 66 million years, that is when the non-avian dinosaurs disappeared from the planet."

Once a dinosaur-obsessed kid, Daniel continues to follow his passion, now with a focus on one of the descendants of avian dinosaurs. He studies penguin fossils and their evolution across time.

The earliest penguin fossils come from right here in Aotearoa, from North Canterbury. Dated to a mere four million years after the dinosaur extinction event - a blink of the eye in geological time - these bones indicate that early proto-penguins had already committed to life in water, although they may not have been very efficient divers.

Birds that fly in the air - like the once-ancestor of the penguin - have hollow bones. But these early fossil bones found in Canterbury are dense, better suited to diving under water.

Across the next 6-13 million years, the wings of these birds underwent significant changes. No longer were they able to tuck back in after a stroke, instead the joints would stiffen so that they effectively became fixed paddles, driven by the shoulder.

The time of the giants

Penguin evolution is constrained by many factors: the difficulty of 'flying' in dense viscous water, the issue of constant heat loss, the need to also go on land to breed. But that didn't stop evolution from testing all the penguin size and shape possibilities within these constraints. And early on in penguin evolution, something interesting happened - penguins get very large. …

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What happens to our muscles as we age? Claire Concannon finds out why muscles get weaker as we get older, and speaks with a researcher investigating why Olympic athletes live up to three years longer than the general population. Claire also meets a scientist studying what happens to muscles in children with cerebral palsy, seeking clues that could help.

'Use it or lose it!' is the rallying cry to exercise. But what happens to our muscles as we grow and as we age?

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In this episode, Claire Concannon explores these questions.

With World Cerebral Palsy Day fast approaching, she speaks to a researcher looking at muscle development in young patients.

Plus, evidence overseas shows that former Olympic athletes live up to three years longer than the general population. A New Zealand study is investigating how former athletes' lifelong commitment to exercise is good for their bodies.

Cerebral palsy and muscle development

Cerebral palsy is the most common cause of physical disability for children in Aotearoa. It results when impairment in the developing brain either during pregnancy or shortly after birth leads to problems with movement and posture.

Dr Geoffrey Handsfield of the musculoskeletal modelling group at the Auckland Bioengineering Institute wants to understand what is happening in the muscles of children with cerebral palsy across time.

To do this, he is working with Mātai Medical Institute in Tairāwhiti on a longitudinal MRI study of children both with and without cerebral palsy.

He hopes to figure out how muscle development is impeded in those with cerebral palsy and perhaps find some clues for how to help.

Muscle changes as we age

At the other end of the life spectrum, Dr Lara Vlietstra of the School of Physical Education, Sports and Exercise Science at the University of Otago is interested in what happens to our muscles as we age.

There are physiological changes that occur - while we only lose a little bit of muscle mass, the muscle fibres themselves change.

Over time, many of our Type 2, or fast-twitch, muscle fibres (related to power and speed) change to Type 1, or slow-twitch.

On top of this, communication between the nerves and the muscles gets impeded.

Reduced physical activity, along with these physiological changes, can result in loss of function in older adults, and susceptibility to falls.

Lifelong commitment to exercise

These changes are both preventable and treatable, says Lara, with - you guessed it - exercise…

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The southern New Zealand dotterel is a true underdog of the bird world, with just 126 individuals at last population estimate. Claire Concannon tags along with a team of researchers attaching trackers to the birds. Their mission is to figure out where the dotterels go to breed, so these "plump little tomatoes" can be protected from introduced predators.

As the tide closes in on Awarua Bay in Southland, a collection of wading birds gathers closer together, pecking away at the last stretches of sandbar and seagrass.

Grey plovers, knots, bar-tailed godwits, banded dotterels, oystercatchers, and a single Terek sandpiper, nicknamed Derek.

And among the crowd, a little flock of southern New Zealand dotterels clusters together - at a quick count: 54 birds. Just under half of the total population.

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Declining numbers

"Since 2010 the dotterel population has more than halved," says Daniel Cocker, a member of the Department of Conservation (DOC) Southern New Zealand Dotterel recovery team. The annual count in April of this year revealed that the population has dropped to just 126 birds.

Plump and handsome - especially when sporting their red-chested breeding plumage - these little birds would once have been widely distributed and bred on mountaintops around Southland. Now, they are restricted to breeding on some of the peaks of Rakiura Stewart Island.

The breeding site secret

It's during this breeding phase that they are most vulnerable to predation, and the main culprit is feral cats. Daniel, and the rest of the recovery team based on Rakiura, are focused on predator control in the areas that these birds are known to breed. But they only know the breeding locations for about 20 percent of the birds - most of them go to mountaintops unknown.

That's why DOC staff and researchers from the University of Otago have teamed up to attach satellite tags to some of the southern New Zealand dotterels in Awarua Bay. When not breeding, the birds flock here, and in a few other bays on Rakiura, feeding up on the bugs in the sand.

Master's student Oscar Thomas is hoping that by adding these tags to the birds, the team will be able to discover where they go.

Listen to the episode to get to know this Southland underdog, hear the story about how Daniel first got involved in their conservation at age 14 and learn how the satellite tags are fitted to the birds.

To learn more: …

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Broccoli and chocolate. Prawns and vanilla. According to food pairing theory, these culinary matches should go together as well as macaroni and cheese, or peanut butter and jam. But do they really? Senior producer Justin Gregory meets two researchers digging into the sensory science of food.

Hungry? How does a nice meal of milk chocolate and asparagus sound?

Or maybe prawns and vanilla? Kiwifruit and gorgonzola cheese?

If scientific theories about the science of food pairing are right, these should be delicious flavour combinations.

Maybe they are. Maybe they aren't... but there's certainly more to it than we currently know.

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Food pairing theory works on a pretty simple chemical basis: foods that share more flavour compounds (mostly smell) will taste better together than foods that don't.

For example, ham and eggs. Macaroni and cheese. Perhaps less obviously, caviar and white chocolate.

But there's a big geographic and cultural hole in this theory.

"Research has shown that there is this tendency for western cuisines to comprise recipes that are combining different ingredients that have shared these flavour compounds', says Dr Rebecca Jelley, a research fellow in the School of Chemical Science at the University of Auckland.

"But in fact, the complete opposite was seen for east Asian cuisines."

And there's another element this theory might be overlooking.

"They seem to have forgotten about the sensory aspects of food," says Dr Danaé Larsen, who is a lecturer in the School of Chemical Science.

By sensory, she means the texture, sound and sight of food and it is this area that the two have begun a research project hoping to find some better answers.

They want to know if adding sensory stimulation while chewing texturally complex foods adds enjoyment and a feeling of fullness after eating.

To test this, the pair are running a series of experiments using New Zealand foods with shared aromatic compounds. Danaé is in charge of the sensory aspects of the study while Rebecca analyses the chemical compounds of the foods used.

The hope is to one day have a local food pairing network backed by solid science - which Central Otago Pinot Noir goes best with which local cheese, for example.

There's also a possibility of positively affecting the way people feel about healthy foods they may not enjoy eating. One day, there might even be a healthier chocolate bar!

To learn more:…

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The Great Ireland vs. New Zealand Bird-off returns for part 2 to decide once and for all which island nation boasts the best birds. Our avian aficionados return to argue their case in front of judge Claire Concannon. Who will fly to victory? Listen to find out - plus learn about the crazy life cycle of the cuckoo and the weird feathers of the kiwi, among many fascinating facts and tales from the world of birds.

Aotearoa New Zealand may call itself the land of birds, but numbers-wise, the title doesn't stack up.

There are just over 200 bird species breeding here in Aotearoa. But Ireland has more than twice as many at over 450 species.

Then why the title? Is it because birds here fill interesting ecological niches that elsewhere are taken up by various mammals? Is it because many of the birds are endemic - found nowhere else on earth?

Or is it simply birding bluster?

There's only one way to find out.

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Welcome back to the Great Ireland versus New Zealand Bird-off. A sporting contest against Ireland taking place this spring that New Zealand actually has a chance of winning.

Last week's opening salvos saw the white-crested sea eagle defeat the moa - on account of not being extinct - and the kea outsmart the northern raven.

Tītipounamu was gifted a win over the goldcrest, in a move Ireland might yet regret, and we finished up with a mighty showdown - Sirocco the kākāpō versus the swallow, herald of summer.

In a controversial decision prompted by childhood memories, the swallow was given the win, to leave everything tied up at two all.

And so, we are back. To sort this out once and for all. We've brought back our two avian aficionados who have answered their nation's calls.

Ireland - Ricky Whelan

Biodiversity officer at Offaly County Council, and co-host of the In Your Nature podcast with Niall Hatch and Birdwatch Ireland, Ricky has been working with birds and in conservation for over 15 years. He is a walking encyclopaedia of bird facts and conservation concerns - and can also bring the smack talk.

If you haven't had your fill of Ricky bird facts after listening to the episode you can find some more on X (Twitter) or Instagram.

New Zealand - Jamie McAulay …

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Welcome to the great Ireland vs New Zealand bird-off. Two islands, a world apart - but which country has the better birds? Two bird nerds champion their nation's birds across four categories in an avian battle for the ages, with Claire Concannon judging the best of the feathered best. Which country will emerge victorious? Listen to find out.

Two islands, a world apart.

One sits at the edge of the Atlantic, cosy and close with its European neighbours. One spun out into the wild Pacific, with 2,000 kilometres of ocean between it and Australia.

New Zealand and (some of) Ireland were once both part of the super continent Gondwana before they went very separate ways.

Cue millions of years of plate movements, of ice ages and warming, of mass extinctions and evolution.

Which leads us to the most important question of our time: which nation ended up the richer, the weirder, the better off for birds?

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Welcome to the Great Ireland versus New Zealand Bird-Off. Undoubtedly the most important contest between these two nations likely to happen any time soon.

In a unique and unknowable competition format and scoring system, representatives from each nation will put forward candidate birds for each category to be judged by presenter Claire Concannon.

Let's meet the representatives.

Ireland - Ricky Whelan

Hailing from the very centre of the country, Ricky is the biodiversity officer at Offaly County Council, and has been working as a conservationist and ornithologist for over 15 years. He likes long walks in the bog, topping up his bird feeders and extolling the virtues of crows to whoever will listen to him.

Ricky also co-hosts the In Your Nature podcast with Niall Hatch and Birdwatch Ireland. Ask him your corvid questions on X (Twitter) or Instagram.

New Zealand - Jamie McAulay

A conservation biologist based in Te Anau, Jamie loves big mountains, deep fiords and lots of rain. Oh, and birds. He really likes birds. Out on the front lines of conservation, Jamie's got tales of cuddling kiwi, catching tītipounamu in the snow, and crazy kea antics.

Jamie posts about his research and conservation work on Instagram and you can learn about his research on alpine pests on YouTube.

The match-ups

Ireland and New Zealand birds will be put head-to-head to compete for each category. Which bird is the smartest - the northern raven or the mischievous kea? The biggest? The smallest? Which is the most connected bird that brings their nation on to the global stage?

Points will be awarded; a winner will be crowned. …

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We've probably all experienced a little bit of tinnitus, or ringing in the ears, at some stage in our lives. But for some people this phantom sound in their brain can be loud, and permanent, and completely debilitating. Claire Concannon speaks to a group of scientists at the University of Auckland who've been researching ways to help for years, and have developed a digital therapy with promising trial results.

Imagine the whistle of a kettle boiling, turned up to full blast, permanently on.

In your head.

How would it affect your mood? Your attention and focus?

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"It's difficult to describe but it just has such an impact on every facet of your life. You know, your sleeping habits, your mental health, your relationships with other people."

Emily Lane was born with a hearing disability and has had tinnitus on and off all her life. But in 2006 it turned up permanently, and it was loud. "It's like a chorus of cicadas living permanently on full blast inside my head."

Many of us will experience a form of tinnitus at some stage in our lives, what Professor Grant Searchfield terms 'nightclub tinnitus'. After a loud night out, we might wake in the morning with a ringing or buzzing in our ears, but it's likely to fade after a few hours.

Head of Audiology at the University of Auckland, Grant became interested in tinnitus when, as a practising audiologist, he didn't have any answers for patients who came to him for help.

Since then, he has been investigating how to help chronic tinnitus sufferers - people who have experienced this phantom sound for more than six months, and whose lives are significantly impacted by it. And one thing has become very clear - this is a condition that varies widely from person to person, therefore the treatment must also vary.

And it's not just the sound that varies, but also the person's response to the sound, and to treatment. This idea underpins the design of the digital therapeutic the team have developed to help tinnitus sufferers. Users get an app on their phone that allows them to select what they need - whether it's nature soundscapes to help the person relax, complex sounds to help them get relief from their tinnitus, or active sound-based games to help retrain the brain.

The team ran a trial using a prototype of this digital therapy and found that, after twelve weeks of use, 65% of patients showed a clinically meaningful change in how badly their tinnitus impacted their lives. This was compared to 43% in the other group, which was given a popular sound therapy app…

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Dr Kate Thomas has exercise on the brain. As an exercise physiologist, she researches how exercise and fasting can change the energy sources our brain uses. And as an ultramarathon runner, she chases that runner's high on gruelling mountain races.

Dr Kate Thomas is a self-described "exercise evangelist". An exercise physiologist, she spends her time researching the impacts exercise has on the body.

But she also practises what she preaches.

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Based at the University of Otago, Kate is investigating what energy sources the brain uses when you put the body under stress due to exercise and/or fasting. While glucose is the preferred energy source for the brain, it can switch things up if glucose is depleted, and this opens different metabolic pathways and products.

"As we age our brain's ability to use glucose declines and that's even more the case in neurodegenerative diseases like Alzheimer's," Kate explains.

"What is important is that the brain can actually use other fuels. And some of these for example are ketone bodies produced during fasting and lactate produced during high intensity exercise.

"One of the theories and what we're trying to explore in this study is whether if we provide the brain with alternative substrates, how it chooses to use those and what that does for the brain's environment. We think that by switching the brain away from using glucose as its main fuel to one of those other substrates, ketone bodies or lactate, that that triggers a bunch of pathways in the brain that help promote neuroplasticity, cognitive function and general resilience to stress."

In particular, Kate is trying to figure out what combination of fasting and exercise might trigger release of a protein called BDNF - brain-derived neurotrophic factor. BDNF plays a role in preserving existing nerve cells and encouraging the growth of new ones. Our levels of BDNF decrease naturally as we age, and in some chronic neurological conditions such as Parkinson's disease.

Dr Kate Thomas monitors data during an exercise experiment.

Study participants are asked to do a series of four trials - the hardest of which involves a three-hour cycle and a three day fast - while Kate monitors effort, blood glucose, products of metabolism and cognitive ability. In this mechanistic study, Kate is "pulling the levers" as she terms it, to figure out which conditions promote greater production of BDNF. …

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How can swaying buildings help diagnose breast cancer? Katy Gosset meets a team of engineers taking inspiration from earthquake engineering to design a new, cost-effective device to help detect breast cancer. Listen to find out how the device works, and how it could help more women get tested sooner.

Every year, more than 3,000 people are diagnosed with breast cancer, according to the Cancer Society.

Eligible women aged between 45 and 69 can get free mammograms, but younger women must decide whether to fund the test themselves.

Researchers might have found a cost-effective way to screen for breast cancer earlier than we do now. Their inspiration? Earthquake engineering.

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"When you're looking at the motion of buildings, you can identify the underlying ground tissue properties," says Dr Jessica Fitzjohn from the University of Canterbury. "By looking at those vibrations, you can know what the soil properties are underneath."

So, why not apply that same concept to breast tissue?

The team have developed a low-cost tool that applies a small vibration and analyses the resulting surface motion. Cancerous tissue is around 4-10 times stiffer than healthy tissue.

The hope is that this device will give more New Zealand women early access to breast screening.

Senior producer Katy Gosset pays a visit to the research team to find out more.

To learn more:

Listen to other episodes from the Our Changing World catalogue on treating and detecting cancer, including this 2022 episode on new cancer immunotherapies and this 2021 episode on medical detection dogs trained to sniff out cancer.

Katy Gosset previously spoke to Professor Geoff Chase about his work with student engineer Francis Pooke on designing a new device that helps tracheostomy efficiency.

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This year marks the 75th anniversary of the rediscovery of the takahē. Claire Concannon sits down with former Our Changing World presenter and takahē superfan Alison Ballance to chat about her new book, Takahē: Bird of Dreams. Plus, we replay Alison's 2018 episode marking the 70th anniversary of the momentous rediscovery, and discuss what's happened in takahē conservation since.

On 20 November 1948, Dr Geoffrey Orbell and three friends headed into a hidden valley in Fiordland's Murchison Mountains with a dream in mind: to find the thought-to-be-extinct takahē.

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When he and the group returned victorious, it made headlines around the world.

November 2023 will mark the 75th anniversary of this rediscovery. So, what's happened in the time since?

Someone who has been following the fortunes of the takahē closely is former Our Changing World producer and presenter, natural history book author, and lover of birds, Alison Ballance.

In November 2018 she joined the celebrations of the 70th anniversary, which involved the release of two takahē into Takahē Valley, the place where they were rediscovered, with family members of the original party who found them.

Alison has just released her latest book: Takahē - Bird of Dreams.

She sits down with Claire Concannon to talk about writing the book, her experiences of seeing takahē in the wild, and how the takahē have fared in the five years since the last celebration.

Listen to hear the recent interview with Alison Ballance, and a replay of the 2018 episode she produced.

To learn more:

Alison also spoke to Kim Hill about the rediscovery and recovery of the takahē.

Turnaround in takahē's fortunes covers the inital release of takahē into Kahurangi National Park in 2018.

Looking for more bird conservation stories? Listen to the Voice of the Kākāpō series - produced by Alison Ballance, all about the rollercoaster ride of the 2019 kākāpō breeding season.

Go to this episode on rnz.co.nz for more details

Every year, tens to hundreds of seabirds fall out of the sky across Auckland city. Disoriented by the bright lights, Cook's petrels crash-land and collide with buildings - but a dedicated group of volunteers hit the pavement to rescue them. Join us on 'Petrel Patrol' and go behind the scenes at a bird hospital, where squid smoothies and bath time help the seabirds find their wings again.

The concrete jungle of inner-city Auckland is no place for a seabird.

But that's where many Cook's petrels, or tītī, end up every year: crash-landed in urban areas after becoming discombobulated by the bright city lights.

Luckily, the Petrel Patrol is on hand to rescue lost seabirds.

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Ariel Heswall, a PhD candidate at the University of Auckland, is the brains behind the volunteer Petrel Patrol, which hits the pavement on early mornings across a few weeks in Autumn to search for grounded seabirds. She was inspired to start the patrol after seeing hundreds of Cook's petrels come into the Birdcare Aotearoa hospital as patients.

Cook's petrels - or "Cookies", as Ariel affectionately calls them - once lived on mountaintops across Aotearoa. But now, they are restricted to three offshore islands. One population lives in the south, on Whenua Hou Codfish Island off the coast of Rakiura. The other lives in the Hauraki Gulf, with most breeding on Hauturu-o-toi Little Barrier Island and a few more on Aotea Great Barrier Island.

The Hauraki Gulf Cook's petrels forage for food in the Tasman Sea, which means they have to fly across the Auckland isthmus to find a feed. With city lights creating disorienting light pollution, this journey is perilous - especially for young fledglings making the trip for the first time. It's these inexperienced birds that often fall victim to the lights - or even collide with buildings - and end up at Birdcare Aotearoa.

Join us as we tag along on a Petrel Patrol, and then visit Birdcare Aotearoa to meet recovering Cook's petrels and learn about what it takes to rehabilitate seabirds from wildlife rehabilitation expert Lynn Miller. Plus, Ariel explains her research into why light pollution affects seabirds like Cook's petrels.

To learn more:

Ariel has started the Protect our Petrels website which includes info on how to safely rescue a grounded seabird.

We have lots of seabird-themed episodes in our back-catalogue, including this one from 2022 on the Karioi Project helping ōi grey-faced petrels near Whāingaroa Raglan, and this interview with seabird scientist Edin Whitehead on seabirds of northern New Zealand.

Go to this episode on rnz.co.nz for more details

Are all snowflakes really unique? What makes some snow better for skiing? And what's the difference between snow and hail? Join Alison Ballance and Katy Gosset as they hit the slopes of Mt Ruapehu and discover a science wonderland of snow.

You've probably heard the poetic fact that every single snowflake is unique.

This might be true on a molecular level, but doesn't quite pan out for macro snowflake shapes, Alison Ballance and Katy Gosset discover in this episode of 'The science of...'.

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Alison and Katy trace the journey of a snowflake from its inception high in the atmosphere to its fate on Aotearoa's mountaintops, and discover why snow is not just important for skiers and snowboarders.

Join us as Alison and Katy hit the slopes of Ruapehu to dive into the fascinating science of snow.

To learn more:

Visit the original episode webpage for The science of snow.

Discover more "cool" science in Physics on ice and Glaciers as barometers of climate change.

Listen to this episode about using historic weather records and machine learning to predict future weather.

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Nuclear fusion is a holy grail for researchers seeking clean energy. This week we head to the south of France with ABC science journalist Carl Smith in this episode from the Strange Frontiers series. Here, a multi-billion-dollar collaboration between several countries called ITER is trying to make industrial-scale nuclear fusion a reality.

What if we could create bountiful supplies of energy with near-zero carbon emissions? That's the promise of nuclear fusion - a reaction where atoms merge.

Fusion is the reaction happening at the centre of the sun and other stars. Unlike nuclear fission or splitting atoms, it doesn't produce radioactive waste.

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Last year, scientists announced a fusion "breakthrough", with one experiment producing more energy than had been put in - generating just enough energy to boil 60 kettles.

Many challenges remain on the journey to achieve large-scale nuclear fusion. At the International Thermonuclear Experimental Reactor (ITER) in the south of France, a team from several countries are working to secure the "holy grail" of energy at industrial scale.

Carl Smith from the ABC goes behind the scenes at ITER for this episode of the series Strange Frontiers. Listen to hear more about the potential of nuclear fusion and the multi-billion-dollar quest to make it a reality.

Strange Frontiers is a seven-part series taking you to remarkable, hard-to-reach and off-limits places where scientists work. Listen to all episodes on the ABC website.

To learn more:

Read Carl's article about ITER on the ABC News website.

Listen to an interview with one researcher behind the "breakthrough" on Nine to Noon.

This Our Changing World episode features Kiwi research aiming to improve solar panels.

The RNZ podcast Elemental features episodes on elements relevant to nuclear energy (both fusion and fission) including Hydrogen, Plutonium and Thorium.

Go to this episode on rnz.co.nz for more details

Tauranga-based producer Justine Murray dons some gumboots and meets some teeny-tiny cockles as she joins a team surveying the Waihi estuary. Professor Kura Paul-Burke is weaving mātauranga Māori and western science together to address questions that local iwi have about the health of the estuary, and what can be done to improve it.

There are many signs in the taiao (natural world) if you look close enough. Like when the tōrea (oystercatcher) strikes at low tide looking for food; these birds love shellfish, crabs and tuangi (cockles). But how long does it stay? And what is the relationship of the bird to what's around it?

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That's just a glimpse into the tohu surveys (observations) that Professor Kura Paul-Burke and her research team are carrying out as part of the research project 'Tāwharautia te wahapū o Waihi - Protect the Waihi estuary' supported by Our Land Our Water and led by Te Rūnanga o Ngāti Whakahemo.

For generations this estuary was used as a mahinga kai (food gathering place) but over the years the water quality has declined, due to increased pathogens and sedimentation, much of which comes from four neighbouring water canals. Kura, the country's first wāhine Māori Professor of Marine Science and Aquaculture, based at the University of Waikato, argues the straighter the canals are, the more likely pollutants or paruparu makes its way into the estuary.

As the water quality declines, the loss of species also means the loss of mātauranga Māori. Kura and her team draw on both western science and Māori knowledge systems in this study.

Integral to the harbour is the nana (seagrass) meadows. Nana is a kōhanga (nursery) and a foraging habitat for young snapper and trevally, but it is decreasing at an alarming rate.

In 1943 nana meadows were plentiful in the Pukehina district. Today there are just two discrete beds left - this impacts the feeding habits and survival rates of tuangi (cockles).

Kura and her team are on a mission to assess the health of the estuary and figure out what needs to be done. Producer Justine Murray joins the team at Pukehina to learn more.

To learn more

Justine Murray spoke to another of Kura's PhD students last year about the resilience of crayfish in Tauranga Harbour.

Listen to 'Collaborating to move freshwater species' to learn about weaving mātauranga Māori and western science together for conservation translocations.

Hear more about using these two knowledge systems together in 'A bridge between science and mātauranga Māori' and 'The science of Matariki'…

Go to this episode on rnz.co.nz for more details

Have you ever had a catchy tune you just can't get out of your head? Most of us can imagine sounds - music, voices, environmental noise - to varying degrees. But about 1% of people can't imagine sounds at all. This lack of auditory imagery is called anauralia. Claire Concannon meets a team of researchers investigating this newly described phenomenon, and speaks to a musician who experiences anauralia.

If I asked you to play your favourite song in your head, how clear would it be? Would you hear all the different instruments - the tone of them, the timbre? Or would it be just a basic melody, as if played from a distance?

Or is this something you just cannot do at all?

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Most people, over 99% of us, can imagine sounds in our head - environmental sounds, music and our own voices. Some of us imagine better than others. But there is a small proportion of people, estimated at just less than 1%, who can't imagine sounds.

This lack of 'auditory imagery' has recently been given a name by psychologist Professor Tony Lambert, based at the University of Auckland, and his colleague. They call it anauralia.

Tony first became intrigued by the idea after reading about people who lack visual imagery. This phenomenon was called aphantasia by Professor Adam Zeman in 2015, whose work was widely reported.

But from Tony's point of view, while aphantasia was getting its day in the sun, a lack of auditory imagery had gone largely unstudied. So, he decided to change that.

The key questions that Tony and his team now want to answer centre around how anauraliacs (people who experience anauralia) process and store information in the present, create and recall memories, and imagine the future. Previous research has linked these particular functions of the brain to auditory imagery, so what strategies do people lacking imagined sound use instead?

PhD candidates Zoé Schelp and Gage Quigley-Tump have used results from the New Zealand Attitudes and Values Survey to start investigating. The survey included questions asking about auditory and visual imagery. Zoé recruited some of those who reported experiencing anauralia to her study of working memory. She uses a simple memory test to challenge both anauraliacs and control participants, and then interviews them about the different strategies they employ. …

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In September 2022, two New Zealand patients became the first in the world to participate in a phase 1 clinical trial testing a new therapy for a rare neurogenetic condition called myotonic dystrophy. Claire Concannon learns about the trial, and how a new Neurogenetic Registry and Biobank covering 70 conditions is helping to connect New Zealand patients with international research.

Our genes control part of our makeup. And we know that variations in different genes can impact whether we are more susceptible to get certain diseases - cancer say, or dementia. This can include multiple different genes and can be tricky to untangle.

But for some people cause and effect are more of a straight line. For neurogenetic conditions, a variation in just one gene results in neurological symptoms - affecting the brain, nervous system or muscles.

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Neurogenetic conditions are the focus of Associate Professor Richard Roxburgh's research at the Neurogenetics Research Clinic at the University of Auckland. Also a practicing neurologist at Auckland hospital, he has seen hundreds of patients that suffer from these diseases.

Being able to give a diagnosis can be a big help for patients, he says. Because these are genetic based and passed down from generation to generation, patients will often have witnessed other family members experience the same symptoms and disease progression.

'Neurogenetic conditions' is an umbrella term covering conditions like Huntington's disease, different muscular dystrophies, Friedreich's ataxia, spinal muscular atrophy - the list is long. They are rare conditions, each with their own underlying genetic cause and range of symptoms and severity.

Their rarity makes them difficult to study, and to develop effective therapies for. Which is why, Miriam Rodrigues, acting on the request of patients, set up a New Zealand Neurogenetic Registry. Now called Pūnaha Io, the registry, and associated biobank, covers around 70 different conditions, with approximately 1300 registered patients out of an estimated 4000 in the country.

It was this registry, and associated research, that attracted the attention of a US based company Dyne Therapeutics. Dyne were scouting for suitable locations for a phase 1 clinical trial into their therapy aimed at helping those with a condition called myotonic dystrophy.

Two New Zealand patients were the first people in the world to take part in this trial in September 2022. …

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Here in Aotearoa, it's the winter solstice: the shortest day (and longest night) of the year. We're marking the occasion with an episode celebrating the starry night sky. Podcaster Max Balloch looks up in search of stories told through constellations, and finds that light pollution is smudging out the stars for many New Zealanders. What can be done to restore our connection with the night sky?

For humans all over the planet, and all across time, the night sky has been a catalyst for storytelling. Different cultures paint the dark with their own stories of the stars, about where they are, who they are, and what they believe.

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This isn't some ancient, forgotten art - it's alive, and it's organic. Victoria Campbell, a passionate educator of Mātauraka Māori and Māori astronomy says the most special star to her is Rehua.

"Rehua in particular is associated with knowledge. And as an educator, I find a really special connection there to be able to bring forth kōrero, or dialogue and discussion, about knowledge for the benefit of us going forward as a nation, and as a population," she says.

Rehua is part of the constellation known in some cultures - including Greek mythology - as Scorpius. In Polynesian cultures, it's known as Māui's fishhook. And in Java, Indonesia, it's referred to as "the brooded swan". These are three interpretations (among many) of the same pattern of stars, illustrating the connection between stars and storytelling that transcends culture, time, and space.

New Zealand has some of the most pristine skies on the planet. Those living in rural areas bathe in the lights of the universe and embrace the warm hug of the Milky Way that streams across the sky.

But for most people on Earth, the sky is being smudged out.

Light pollution, which occurs when excess light is reflected into the sky at night, is experienced by 83% of Earth's population. This yellow haze outshines the stars and melts the Milky Way out of view.

While many New Zealanders enjoy darkness, over half are left blinded by the light. Fifty-six percent of kiwis cannot see the Milky Way in the night sky, due to the light pollution leaking out from urban environments.

But it can be stopped, and we could have dark skies once again. Steve Butler, an award-winning DarkSky advocate, is one of the many kiwis fighting for the night.

"We sell ourselves as, you know, 100% pure. So, my view, is that to achieve 100% pure we should be looking after the night as well, so that's 50% of our environment," he says. …

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Rats giggle. Dogs wag their tail. How do other animals express joy? You can't ask them, so researchers have to find other sneaky ways of figuring out animal emotions. Professor Ximena Nelson is studying how curious and intelligent kea, New Zealand's alpine parrots, might show positive feeling.

Some rats giggle when their bellies are tickled. Researchers have known it for some time now, though it requires special microphones to detect this - they giggle at an ultrasonic frequency.

It's just one way that one animal expresses joy. How might others be doing it?

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Negative emotions are a bit easier to study, says Professor Ximena Nelson from the University of Canterbury. The animal might yelp or flinch, retract a limb, or shy away. But positive emotions are trickier. You can't ask the animal, and you can't look for those telltale signs in humans - a smile or crinkle around the eye, especially if the animal has completely different facial muscles, as is the case for kea.

It's a multi-step puzzle. Starting with: is the animal even likely to experience positive emotions? For kea, Ximena had her own anecdotal observations of them playing in the mountains as the first clues that they can be joyful. From there, she and her team investigated the different calls that kea made, and then analysed the different behaviours of the kea as they made these calls, to try to discern their functions.

This proved extremely difficult, but one call did seem to be strongly linked to play - the warble call, or kea laughter as it is called. To confirm this, the next step was a series of playback experiments. Design a kea-proof speaker, bring it high into Arthur's Pass, and then investigate what the kea do when you play different calls and other sounds to them.

Turns out the warble call is like a play contagion. Kea were more likely to start playing after hearing the call, and to warble themselves.

Ximena is now focused on trying to determine if this is a reflection of positive emotion such as joy, and if so, does it influence the bird's decision making, as it does in humans? This trickier second step will have to be done using captive kea that can be trained to take part in a glass half-empty or half-full experiment.

Listen to the episode to learn about the how and the why of studying positive emotions in animals.

To learn more:

Listen to this episode from Alison Ballance, who visited Ximena's spider lab to learn about jumping spiders

Listen to 'Kea get a helping hand' which covers citizen science efforts to help curious kea

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There's nothing like a good birthday party, especially one filled with games and fun activities. The Auckland Bioengineering Institute might have missed their 20th birthday due to Covid-19, but they were determined to throw a good ole shindig. Claire Concannon visits to find out what they've been up to for the past 20 years, and what the plan is for the next two decades.

How do you throw a good birthday party?

Have a nice big venue. Invite everyone. Fill it with music, lights, balloons, holographic displays of the respiratory system, computers you can control using your mind, interactive surgery games, giant inflatable colons.

Okay, so maybe the Auckland Bioengineering Institute's 20th birthday party is a little bit different to the usual.

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"The ABI turned 20 at the start of Covid. We wanted to celebrate - of course we couldn't, so now we are putting on this event and inviting the public in," says Professor Merryn Tawhai, deputy director of the Auckland Bioengineering Institute (ABI).

Merryn explains that, although celebrations were pushed back a few years, they wanted to mark their two decades of research with style. So, they filled The Cloud on Auckland's waterfront with displays, games and activities based on the work they do from 9 -14* May and opened it up to everyone.

The 'Bioengineering the future' event was a celebration of what the institute has been working on, and what it is working towards. Their research is wide ranging - from fundamental research into how the body works, to developing instruments to improve diagnosis and treatment of disease, to biomimetics and biorobotics.

One idea that they've been working on for some time is the concept of a 'digital twin'. This would be an online model of a person, created using real data and tuned to exactly how that person's body works. This means you would be able to 'test' things in advance on this digital twin. For example, testing if certain drugs work to help an individual, or not.

To create a digital twin - which models how all the body's systems work together - you need fundamental understanding across molecular, cellular, tissue, organ and system scales.

Working to understand the heart at cellular, tissue and organ level is Dr JC Han. JC is focused on how the heart muscle contracts to pump blood around the body, and specifically how much energy it uses to do this. Working with rat animal models and a specific instrument developed at the ABI, JC wants to understand the efficiency of the heart muscle system, and what happens when things go wrong…

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In Aotearoa we talk a lot about mammalian predators attacking our native wildlife, but other insidious pests are quietly taking over - weedy plants. Tackling these weeds using chemical and mechanical means only gets us so far, so researchers and conservationists also look towards the plants' natural enemies to help. Claire Concannon visits a group of Manaaki Whenua - Landcare Research scientists investigating biocontrol agents to assist in the fight.

Aotearoa is in the weeds.

There are around 2300 species of native New Zealand plants, but an estimated 25000-30000 species of plants from overseas.

And many of them have gone rogue.

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Without their natural predators, which co-evolved with them to keep them in check, some of these plants have escaped out of our houses and gardens.

The worst of weeds grow rapidly, spread voraciously and smother and kill native plants. Traditional chemical or mechanical control methods - spraying herbicides or pulling out the weeds - are expensive, time consuming and short-lived. So, what else have we got in the toolbox?

One option is biological control, or biocontrol for short. This involves finding a natural enemy of the weed from its host country to keep it in check. Some insects, mites and plant pathogens have evolved to be extremely plant specific, and these are the agents that Dr Angela Bownes is keen to recruit.

Angela is a senior researcher in weed biocontrol at Manaaki Whenua - Landcare Research. Based on their research campus in Lincoln, she works closely with fellow senior research Dr Ronny Groenteman to investigate different agents that might be helpful in the battle against weeds.

The research they do is to aid the National Biocontrol Collective - a consortium of regional councils, unitary authorities, and the Department of Conservation. The National Biocontrol Collective funds the applied weed biocontrol research that takes place at Manaaki Whenua and has worked with them to develop a weed prioritisation tool to build a hit list of the top weeds to target.

At the Lincoln campus the researchers work in the specially designed invertebrate containment facility to put the biocontrol agents through their paces. Arnaud Cartier manages the facility, ensuring all the restrictions are in place so that no agent escapes before it is approved for release.

Listen to the episode in which Claire Concannon visits the facility to learn more about biocontrol agents, how researchers ensure they are safe to release, and the hurdles an agent must clear before approval

To learn more: …

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This week we're digging up the dirt on the surprising complexity of soil. From top-notch compost to dung beetles to kauri dieback, join us on a fascinating tour of the world beneath our feet with presenters at the Wild Dunedin Festival of Nature.

Professor Amanda Black is a big picture thinker. She likes the idea that we are just tiny dots in a vast universe. Little surprise then that her science career led her to studying soil, one of the most complex and varied ecosystems there is.

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Amanda is the director of the Bioprotection Aotearoa Centre of Research Excellence. Formerly known as the Bio-Protection Research Centre, it was re-funded in July 2021 with a new approach in mind for how to tackle the tricky job of protecting New Zealand's productive landscapes.

Her own research has led her from investigating how movement between landscapes affects the kauri dieback pathogen, to re-establishing land-sea connections in the hopes of increasing soil resilience to this disease.

Based at Lincoln University, Amanda was one of the visiting speakers to the 2023 Wild Dunedin Festival of Nature. In its eighth year, the theme for this year's festival was whenua. More than 120 events across ten days celebrated the land and soils.

As every other year, the festival began with the 7 x 7 Wild Talks event. Seven speakers are given seven minutes to talk about their chosen topic. University of Otago PhD candidate Emma Curtin used her time to talk about the insect she studies: dung beetles. These beetles are a relatively new arrival to Aotearoa, and Emma is investigating the benefits they might deliver for farmers.

Another visiting speaker was Jim O'Gorman, known as the Dirt Doctor. Across composting workshops and talks, Jim shared his knowledge about how to create healthy, productive soils.

Listen to the episode to hear more about Bioprotection Aotearoa, Amanda's research work, and about dung beetles and composting!

To learn more:

Our Changing World has extensively covered kauri dieback disease.

Jim O'Gorman previously featured on Country Life.

The connection between seabirds and the land is something the team at Auckland War Memorial Museum is also investigating in the Noises Islands in the Hauraki Gulf.

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Claire Concannon meets the latest addition to the Zealandia ecosanctuary family - toitoi, or common bully. Zealandia CEO Dr Danielle Shanahan explains why these little fish will be an important part of the freshwater ecosystem, and what their ambitious 100 year plans are to restore the mouri or lifeforce of the entire Kaiwharawhara catchment.

The native birds are loud and proud at Te Māra-a-Tāne, Zealandia.

They flit amongst the canopy, call from the branches, preen on their perches, and even stroll across the paths.

But today we look past the manu, and instead focus on the humble freshwater fauna living their quiet lives amongst their boisterous feathered brethren.

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Most of Zealandia's freshwater areas are in fact manmade. The Karori upper and lower dams, completed in 1908 and 1878, were in use as drinking water reservoirs until the 1990s, when they were decommissioned due to earthquake risk.

Now part of the fenced ecosanctuary, the team at Zealandia have taken on the task of restoring some of the native wildlife that once would have been present in this catchment.

The Kaiwharawhara stream is born at the top of the sanctuary, collects in the dammed upper reservoir, feeds down through a man-made wetland area to the lower reservoir and then winds its way through the western suburbs and down the Ngaio Gorge, finishing its journey at Wellington Harbour beside the ferry terminal. So, an incredibly modified, urban landscape.

To restore this valley to a hint of its former glory will take a lot of work. But CEO of Zealandia, Dr Danielle Shanahan, remains undaunted: "This is a 100-year vision of restoring the mouri or lifeforce of this absolutely incredible catchment." This collaborative project - Kia mouriora te Kaiwharawhara, Sanctuary to sea - will involve dealing with historic landfills within the catchment, providing fish passage for native ika to be able to move upstream, and advocating to ensure future developments are freshwater friendly.

For Danielle, it must start at home. She and the Zealandia team have been working hard to restore the upper reservoir (now called Roto Māhanga), the lower reservoir (referred to as Roto Kawau after the shags that hang out there), and the wetland area in between.

The most recent addition is toitoi, the common bully, to Roto Māhanga. These are cute speckled brown fish that are an important part of another freshwater resident's lifecycle. Kākahi, or freshwater mussels, sneeze out their larvae which then attach to the gills of fish like toitoi in order to disperse. …

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What are the risks of head injury for players of contact sports such as rugby? Research is increasingly linking head knocks with neurodegenerative diseases later in life. Claire Concannon meets a research team analysing every rugby training session and match across an entire season with high-tech mouthguards.

Grace doesn't think about head knocks when she plays rugby: "If you see your teammates get concussed it can be scary, but when you're playing, I feel like it doesn't cross your mind, you are just more focused on the game."

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But increasingly researchers, clinicians, governing bodies, parents, and players are thinking about it. With increased research linking head knocks with neurodegenerative diseases later in life, and legal proceedings being issued by rugby union, rugby league and football players to various governing bodies, now, more than ever, people want to understand what the risks are, and how to mitigate them.

While to date there has been a gap in knowledge about the risks at a junior level, there are a few studies currently underway in Aotearoa aimed at filling this.

One is working with Grace's team.

Led by Professor Nick Draper at the University of Canterbury, the study aims to follow 40 junior male and female rugby players across every training and game in one full season to work out what their exposure is in terms of number of incidences, and their magnitudes.

Nicole Spriggs, a PhD candidate at Lincoln University, is tracking the girls' teams. She does this by using mouthguards that are moulded specifically for each player using dental scans, and which contain accelerometers. They are set to measure any head acceleration event over eight G - an equivalent to your head wobbling as you bounce on a trampoline. To verify each incident Nicole also videos each training and match.

While Nicole is focused on investigating incidences in female junior players, her University of Canterbury PhD colleague Stefan Henley is focused on doing the same with under 16 boys' teams. All players also do an MRI and neurocognitive test before and after each season that Nicole and Stefan will use to investigate if there have been any changes in the structure and function of the player's brains. …

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Meet the winners of the 2022 Prime Minister's Science Prizes! We go behind the scenes with the Emerging Scientist, Science Teacher and Future Scientist winners to learn about cutting-edge research, inspiring teaching and intriguing mahi worthy of these prestigious awards.

It's time for the Prime Minister's Science Prizes!

Every year, five prizes are awarded to emerging and established researchers, science communicators and educators at the top of their game.

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The main prize, Te Puiaki Pūtaiao Matua a Te Pirimia, was awarded to the multidisciplinary National Institute for Stroke and Applied Neurosciences at Auckland University of Technology.

Led by Professor Valery Feigin, the team has done extensive investigations into stroke incidences and burden worldwide.

Now they are focused on developing the most cost effective, widely applicable strategies to reduce stroke incidences, including a free mobile app called Stroke Riskometer aimed at helping people lower their individual stroke risk.

Congratulations also to Associate Professor Dianne Sika-Paotonu, who won Te Puiaki Whakapā Pūtaiao - The Prime Minister's Science Communication Prize. Based at the University of Otago, Wellington, Dianne is an immunologist and biomedical scientist. The focus of her mahi is on addressing health inequities that exist for Pacific and Māori communities, through research that is grounded in respectful and inclusive engagement with these communities.

She was a key science communicator during the Covid-19 pandemic, and a strong proponent for Pacific and Māori researchers and health professionals to be given the opportunity to lead and make decisions for their communities.

On this week's Our Changing World we meet the other three prize-winners and learn a bit more about their award-winning mahi.

Te Puiaki Kaipūtaiao Maea / The Prime Minister's MacDiarmid Emerging Scientist Prize - Associate Professor Jonathan Tonkin

Dr Jonathan Tonkin began his research career sloshing through rivers in Tongariro National Park when he studied benthic invertebrates for his PhD. Today he has mostly hung up his waders.

Now, from his office in the School of Biological Sciences at Te Whare Wānanga o Waitaha, the University of Canterbury, Jonathan has a new key role: mentoring the large number of students and scientists that form his research group. Their research focus is on creating models to forecast how different communities of organisms will respond to environmental threats. …

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Tropical cyclones can cause rampant destruction, but sometimes, these wild weather systems can seed life at sea too. This week we meet a storm-chasing researcher in search of phytoplankton blooms like one that formed in the wake of 2019 Cyclone Oma.

Dr Pete Russell is a storm chaser.

But that doesn't mean he's driving new-fangled-looking machinery into the path of tornadoes or sailing ships to intercept hurricanes.

He chases storms from his shared office in the marine science department at the University of Otago.

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For the past seven years, Pete has been keeping tabs on tropical cyclones in the South Pacific via storm track data and satellite pictures. He is looking for a particular type of tropical cyclone - those that result in phytoplankton blooms.

Tropical cyclones can only form over warm water that is at least 26.5℃ for the first 50m. Spurred on by some disturbance, warm moist air rises off the ocean. As it rises, it cools, and the water vapour condenses into liquid droplets that form big clouds. The rising air leaves an area of low pressure, so wind comes in from the side to fill this, which in turn warms and rises. This sets up a positive feedback loop where the cyclone continues to 'feed and grow' off the warm water it travels over.

The winds whipped up by a tropical cyclone will disturb the temperature layering of the ocean. This means if it were to hover for long in one position, the cyclone would essentially put itself out by pulling up colder water.

If it tracks in one direction, the disturbance at the front of the cyclone is reversed by the tail end - as the winds will blow in opposite directions.

But if the cyclone hovers for a while, and changes direction, then it might cause a large amount of colder water to be pulled to the surface in its wake. This cooler water from further down in the ocean column contains nutrients, and when the storm passes on and sunlight hits this patch of cooler water, it can lead to large phytoplankton blooms.

By looking at storm track data that shows the path of tropical cyclones Pete can predict whether they will result in a phytoplankton bloom. Satellite images of ocean colour, tuned to the chlorophyll A in phytoplankton, can then confirm this.

Listen to the episode to learn about one particularly large bloom event in 2019, and how these blooming cyclones might be the key to us predicting the future of tropical cyclones in a warmer South Pacific Ocean.

The stormy Southern Ocean …

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Grab your gumboots! Alison Ballance squelches out into Nelson's mudflats with a team of Cawthron Institute researchers in search of cryptic seagrass flowers and their seeds. Collecting the seeds is step one in an ambitious project to restore Aotearoa's ailing seagrass meadows.

Nelson's Haven is an 8-kilometre expanse of mudflats. If you don gumboots and squelch your way out at low tide, you'll find it is also an expansive grassy meadow.

The grass is seagrass, the only flowering plant that lives in the sea. It provides key habitat for many fish species, as well as performing a vital ecological role cleaning water, stabilising mud and sequestering carbon.

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Marine ecologists from the Cawthron Institute have just completed the first summer of a three-year research project to develop new ways of restoring seagrass meadows - using seeds.

Until recently, it was thought that seagrass in New Zealand, which belongs to the species Zostera muelleri, only rarely flowered and set seed. But the marine restoration team at the Cawthron Institute have discovered there are actually plenty of flowers, although team leader Dr Dana Clark admits the greenish flowers are cryptic and hard to find.

The Haven is one of three study sites near Nelson, along with Waimea and Delaware / Wakapuaka estuaries, for the project Restoring Aotearoa New Zealand's Seagrass Meadows. Over the past summer, the seagrass team has been surveying its field sites and monitoring flowering. The researchers have discovered that flowering begins in October and ends in February, with peak flowering in December.

Dana says the team collected about 3000 seagrass flowers, which were taken back to the lab. Here they were kept in two tanks of bubbling water which marine ecologist Dr Anna Berthelsen describes as a 'seagrass spa.' The bubbles keep the seagrass well oxygenated as they mature, allowing them to develop naturally and shed pollen into the water which fertilises female flowers that go on to develop seeds.

Dana says they were thrilled to collect nearly 600 seeds, which are being stored ready for germination trials. Armed with this summer's findings, she hopes the project will produce even more seeds next summer. …

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The birds are back. After a long absence, 11 kiwi have returned to the outskirts of Wellington with a little help from some human friends. Veronika Meduna heads into the field to see how the work of the Capital Kiwi Project is paying off.

Imagine taking an evening walk around the fringes of the capital city and hearing the call of the kiwi.

Well, you no longer need to imagine.

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This vision of kiwi once again roaming the windswept hills on the outskirts of Wellington is becoming reality with the arrival of 11 North Island brown kiwi, set free in the scrubby landscapes around Mākara late last year.

This flock is just the beginning. The ambitious Capital Kiwi project plans to bring back 250 kiwi over the next six years to re-establish a thriving population on 23,000 hectares of land that stretches from the Red Rocks on Wellington's south coast all the way to Porirua. The first pioneers are a gift from the Ōtorohanga Kiwi House and Ngāti Hinewai to the local community and Taranaki Whānui.

The Mākara community have put in years of hard work (and more than 4500 traps) to clear introduced predators and make the area as safe as possible for the new residents.

"In unmanaged sites, 95% of chicks are eaten by stoats. To grow a kiwi population, you have to have one in five chicks survive, but we're aiming to do much better than that," says project founder and leader Paul Stanley Ward. "What we'd like to have is a self-sustaining, wild, free-ranging population of kiwi where they can live as they have done for millions of years in these hills."

"Fundamentally, if our relationship with a bird like the kiwi ends up being behind a fence or in a zoo, we'll lose our aroha to care for them. But we know we can recover kiwi populations - and for us, it's about doing that in the backyard of our capital city."

Thank you to Dave Allen for providing photos for this story. www.daveallen.photography

To learn more:

Watch this short piece about the second release of kiwi from Sanctuary Mountain Maungatautari

The tracking of this first release was also featured in Summer Time in January 2023

Visit the Capital Kiwi Project website.

In 2018, Alison Ballance reported on the rise of native birds in Wellington.

Go to this episode on rnz.co.nz for more details

The Rotopiko peat wetlands are a haven for rare and threatened wildlife. But when a flock of introduced birds numbering in the hundreds of thousands moves in - threatening the very nature of this special place - a group of people come up with some crazy-but-genius ideas to protect the wetlands and wildlife. Claire Concannon investigates.

Half an hour south of Kirikiriroa Hamilton, the Rotopiko wetland reserve is an oasis of trees in a desert of farmland.

At dusk, these trees fill with hundreds of thousands of starlings and sparrows, jostling for position on the branches, like noisy restless shadows.

It's an incredible spectacle... but these birds are not welcome here.

Listen to the story

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"These birds are bringing in massive amounts of nutrients," says Karen Denyer, the executive officer of the National Wetland Trust of New Zealand.

"'We are trying to restore this wonderful site... and we've got this unintentional and kind of unexpected problem."

Rotopiko is a peat lake wetland complex. An ecosystem naturally low in nutrients, to which some rare native New Zealand species are perfectly adapted. For example, the endemic giant cane rush, and the caterpillar that lives inside it. They were translocated into the sanctuary years ago, as the group set about restoring the area.

It's been a lot of work - a massive weeding effort, erecting a predator-proof fence, removing predators, building paths and a boardwalk, creating an information trail, replanting kahikatea trees.

But now it's at risk.

Just two years after the predator-proof fence was put up, and the predators removed, birds started to come to roost at night inside the ten-hectare fenced area in large numbers. The nutrients in their droppings threaten to change the very nature of the wetland.

Because there are so many birds it's a major challenge to count them. Researchers from Toi Ohomai Te Pūkenga and Wintec Te Pūkenga have come on board to help. They have developed different methods to estimate changes in the number of birds, so the Wetland Trust can test the effectiveness of different deterrents.

Laser lights, noise, shooting, a product like pepper spray for birds, wood vinegar - nothing has worked so far. This has forced the Wetland Trust into trying a less desirable and more controversial method - returning rats to a rat-free area.

Listen to the episode to learn more about the Rotopiko peat lake complex, the flora and fauna that live there, and to hear the incredible sound of hundreds of thousands of roosting birds.

To learn more: …

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As mountains get warmer with our changing climate, what will happen to the iconic alpine plants that live at high altitude? Claire Concannon visits the moonscape slopes of Mt Ruapehu with a team of researchers using an experimental set-up that's part-greenhouse, part-UFO.

It looks like the work of a small alien race. On the moonscape slopes of Mount Ruapehu, hexagon shapes enclose small patches of scrubby plants.

But these are not UFOs. These contraptions are more like time travel machines.

Listen to Our Changing World

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This alpine habitat plays host to a climate change experiment, investigating what will happen to plants here in a warming world. The hexagonal perspex chambers heat the soil and air temperature by 2°C - the predicted average rise in temperature in alpine regions up to 2070.

The site is one of just 20 worldwide that form the WaRM network - Warming and Removal in Mountains. Dr Julie Deslippe of Te Herenga Waka, Victoria University of Wellington, leads the research at these sites in Tongariro National Park.

The New Zealand team regularly monitor the plots to answer questions about what will happen to the biodiversity and carbon flux of these ecosystems as they heat up. Which plants are winners? Which are losers? Will heating mean the plants grow bigger, photosynthesise more, and take up more carbon? Or will the warming stress the plants out, meaning they respire or 'breathe out' more carbon?

Around the world there are ten countries with ten mountains participating in the WaRM network. Each has both a high- and low-elevation site on the same mountain, separated by at least 500m of altitude. The experiments are set up and monitored the same way in each location. Records are taken of the soil and air temperature, the plant species, percentage coverage and biomass, and the carbon exchange happening between the plants, soil and the atmosphere.

In some 'removal' plots, the most prevalent plant in the area has been taken out to see how this impacts plant biodiversity. At the low-elevation site in New Zealand, this dominant plant is invasive heather, so these plots give a window into what the future might be like if ongoing heather control methods prove successful. The research has been underway for eight years now, and with all this data, the team are starting to figure some things out.

Listen to the episode to find out what they have learned about the future of our alpine plants.

To learn more: …

Go to this episode on rnz.co.nz for more details

This week, Claire Concannon returns to the Noises Islands in the Hauraki Gulf. While conservation action on the islands has led to thriving terrestrial ecosystems, under the water, it's a very different story. Listen to learn how the marine environment has declined around the Noises, and what might be done to reverse it.

Lifting the burden of rats in the forests of Ōtata Island has allowed life to flourish there: the plants, the birds, the lizards, the insects. But while things have been improving on land, under the water it's a very different story.

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Sue Neureuter spent her childhood exploring this island along with her brother Rod and sister Zoe. Her family has memories of abundance: hundreds of nesting seabirds, great big schools of kahawai, kingfish jumping in the bay, plentiful crayfish. But today these are just memories.

"Now when I snorkel it's a relief to find things," says Sue.

Ōtata Island is the largest in the Noises Islands group, now owned by the Noises Trust, which the Neureuter family set up in 1995.

Spurred by the loss they were witnessing, Sue and her siblings reached out to Auckland Council and the Department of Conservation. So, when the Sea Change project was established in 2013 to lay out a plan to reverse decline across the Hauraki Gulf, they became part of the conversations.

From there, a collaboration developed between the Noises Trust, Auckland War Memorial Museum, and the University of Auckland. Marine surveys confirmed a wide range of underwater habitats - a diversity researchers deemed worth protecting.

In June 2021 the government released the 'Revitalising the Gulf - Government action on the Sea Change Plan' with a wide range of proposed actions to help the Hauraki Gulf, including new high protection zones. In September 2022, another proposed high protection zone was added: a 60km² area around the Noises Islands.

With Tāmaki Paenga Hira Auckland War Memorial Museum, the Noises Trust has also developed a long-term monitoring strategy, so that they can track any changes that happen if the marine area around the islands gets protected.

Listen to the episode to hear Sue's stories of loss and hope, plus the work of researchers from Auckland Museum to document the ecology of the Noises Islands.

To learn more:

Listen to The Noises Islands, Part 1 to learn about the history of conservation research on these islands.

In 2014 Alison Ballance talked to many different groups about the declining state of the Hauraki Gulf and the initial stages of the Sea Change project. …

Go to this episode on rnz.co.nz for more details

The Noises are a conservation success story in the Hauraki Gulf. Claire Concannon joins a team surveying the wētāpunga, seabirds, and other flora and fauna that now thrive on these predator-free islands.

On the small island of Motuhoropapa sits an old hut. Once it housed researchers who spent three years studying Norway rats, before dealing to them. Today new residents have moved in: giant wētā now thrive on this predator-free island.

Listen to Our Changing World

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The creaking wooden door opens up to a house-of-horrors scene - or exciting insect menagerie, depending on your persuasion. Brown pellets litter every surface. The culprit, a wētāpunga, casts a watchful eye from a dark corner high in the rafters above.

The first translocation of 1200 wētāpunga to Motuhoropapa took place in 2015, long after the rats had been removed. The giant wētā have made the forest theirs. But they are only one small part in the much larger picture of life on the Noises Islands.

Like little dribbles of paint that have dripped off a brush into the ocean, this collection of reefs, rock stacks and small islands sits in the inner Hauraki Gulf. Rakino Island is the nearest neighbour looking back towards Auckland, with the expanse of the outer gulf in the opposite direction.

The island group has been owned by the Neureuter family since 1933 when it was bought from a retired ship captain for 200 pounds. In 1995 the family formed the Noises Trust to help ensure long-term protection, and the islands were gifted to the Trust. The family's goal is to continue the history of conservation research and education on and around the Noises.

The most recent effort involves working with Tāmaki Paenga Hira, Auckland War Memorial Museum, to establish a comprehensive, long-term survey of the islands' ecology. To do this, researchers from the museum travel to the islands each year to monitor seabirds, and to assess the vegetation, insect populations and forest bird diversity at specific plot sites. This will allow them to track changes in the island biodiversity and ecology over time.

And what could cause a major change in island ecology? Well, marine protection around the area might... But whether and when that will happen is still unknown.

Claire Concannon joins the group as they conduct their survey work to find out about the history of conservation on the islands, the cool creatures that call them home now, and their hopes for the future. Listen to the episode to hear part one of a two-part piece on the Noises Islands.

To learn more: …

Go to this episode on rnz.co.nz for more details

We all get some - but are you getting enough? Claire Concannon investigates the science of sleep and meets a pilot-turned-sleep-researcher helping the aviation industry ensure crew on long-haul flights get some shut-eye.

Sleeping isn't clever, evolutionarily speaking. We spend a third of our lives in an extremely vulnerable position, unaware of our surroundings, exposed to threats of predators. But while researchers are not fully sure exactly what the purpose of sleep is, it's clear that we need it.

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"Sleep is an absolutely fundamental biological process. It is as important to us as eating and drinking," says Professor Leigh Signal, who is on a campaign for the vital importance of sleep to be recognised. She's a professor in fatigue management and sleep health at Massy University, Wellington, with a focus on applying sleep science to workplace settings.

For her work, Leigh stays up to date with the ever-evolving and wide-ranging research related to basic sleep science. As more and more experiments are done, the importance of sleep becomes more evident. Lack of sleep impacts our mood, our emotional regulation, our immune system functioning, our metabolism and how we function on different basic tasks. When it comes to workplace settings, sleep is vitally important in terms of preventing fatigue-related accidents.

Having trained as a commercial pilot before moving into academia, Leigh is particularly suited to helping the aviation industry address the challenges many of its staff are faced with. Long work hours, changing time zones, shifting daylight hours that impact our biological clocks, and critical safety tasks that require people to be functioning well and working as a team.

Listen to the episode to learn about the basics of sleep science, what happens to us when we don't get enough, and about the planning behind the inaugural Air New Zealand Auckland to New York flight to ensure that the crew got enough sleep on the job.

To learn more:

This episode contains excerpts from The Secrets of Sleep documentary and the Eyes Wide Open episode of the Hidden Brain podcast.

There have been previous Our Changing World episodes related to sleep, including one on Sleep Apnoea, Shining a light on our biological clock, and What it takes to live a good life.

Go to this episode on rnz.co.nz for more details

New Zealand's native long-tailed bat, pekapeka-tou-roa, is going strong in Franklin, south of Auckland. But these tiny mammals are threatened by introduced predators, especially cats. Producer Liz Garton goes on a bat hunt and learns about locals' efforts to keep their pekapeka neighbours safe.

A recent survey of the long-tailed bat population in Franklin, south of Auckland, showed there were many more pekapeka than expected.

Join producer Liz Garton as she heads out on a bat hunt, with the batman Ben Paris and some keen locals.

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https://players.brightcove.net/6093072280001/default_default/index.html?videoId=6320281807112

More than half the survey sites in Franklin detected the presence of bats, but these mysterious mammals are not easy to find or spot.

Pekapeka-tou-roa, or the native long-tailed bat, are a threatened species and they seem to be a tasty treat for all Aotearoa's introduced pests.

And a recent DOC study identified cats as some of the worst offenders.

There is currently no national legislation for managing cats in Aotearoa, but many conservation and animal welfare groups are keen to see a move towards this.

At an individual level, SPCA science advisor Christine Sumner says keeping your cat home is the solution to keeping native species safe.

The SPCA have lots of suggestions for keeping your cat happy and still being a responsible cat owner.

In Franklin's Patumahoe, a concerted effort to reduce pest numbers using an award-winning trap has not only improved native bird numbers in the area, but also seems to have had a positive impact on bat numbers.

To learn more:

Find out more about Tāmaki Makaurau's bat population at Auckland Council.

This study looks at what is predating on pekapeka.

Get tips on keeping your cat happy at home from the SPCA.

Read about Andrew's smart trap on Predator Free Franklin.

Go to this episode on rnz.co.nz for more details

Not everything goes to plan on research trips. And when the trip is to a remote island aboard a navy ship designed to help with disaster relief, and happens to overlap with one of the worst weather disasters in New Zealand... well, things are going to change. Claire Concannon tells the story of Operation Endurance 2023 on Campbell Island.

We thought this episode would be different. Maybe filled with the noisy shriek of hoiho as researchers fit them with satellite tags, or the chortle of southern royal albatrosses as Department of Conservation rangers check their nest numbers. But, plans change.

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And so it was for people aboard the HMNZS Canterbury last week for Operation Endurance.

Op Endurance is a long-running collaboration between the NZ Defence Force and government agencies to enable research and conservation work in far-flung New Zealand territories.

As part of the operation this year, staff and representatives from DOC, MetService, the Defence Technology Agency, the Sir Peter Blake Trust, and mana whenua Kāi Tahu were all onboard.

The plan was to sail 660km south from Bluff to subantarctic Campbell Island. Over 10 days, the defence forces would facilitate the transfer of equipment and personnel that would allow different agencies to get their work and research done.

DOC had plans to do hut and track maintenance and inspection, as well as research on hoiho, sea lions and albatrosses. MetService wanted to do some clean up tasks at their old meteorological station. The Sir Peter Blake Trust had a team of scientists, students and teachers planning to collect samples for a range of scientific investigations. And so on.

The HMNZS Canterbury is a good fit for the operation. As well as its massive cargo space to accommodate numerous shipping containers and heavy equipment, it can sleep over 360 people, and onboard it houses helicopters, Zodiacs and rigid-hulled inflatable boats to shuffle things to and fro.

These features also make it an excellent humanitarian and disaster relief ship.

And so, after just one night at Campbell Island, the HMNZS Canterbury was recalled to help with the impacts of Cyclone Gabrielle.

Thus began a massive effort to get as many tasks completed as possible before the ship departed north again. Birds were tagged, fixes were made, clean-ups completed, wave buoys deployed, and communication methods trialled. Peat, plankton and kelp samples were collected, as well as a rock that could turn out to be an important taonga for Kāi Tahu…

Go to this episode on rnz.co.nz for more details

This week we're travelling back in time 66 million years ago with producer William Ray, to a time when dinosaurs roamed. Join William as he meets two Tyrannosaurus rex fossils at the Auckland Museum and uncovers the story behind the bones.

In 2022 Auckland War Memorial Museum received two new guests: a pair of gigantic fossilised Tyrannosaurus rex skeletons.

Join producer William Ray as he meets the dinosaurs and then discovers the story behind the bones with University of Kansas palaeontologist Dr David Burnham.

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Scientists who've studied the fossils say they have evidence of dramatic injuries, which might shed light on the lifestyles of these deadly dinosaurs.

The first, nicknamed "Peter", has a devastating injury to his femur, which seems to have been bitten in half by another T. rex in a battle over territory or mating rights.

The second, "Barbara", has a significant injury to her foot, which would have made it extremely difficult for her to hunt. Some scientists say the fact this injury healed might suggest she was helped to find food by other tyrannosaurs - hinting at a more caring, social side to these dinosaurs.

To learn more:

Info about Barbara and Peter is available on Auckland Museum's website.

Auckland Museum chief executive Dr David Gaimster spoke to Karyn Hay on Nights about the two tyrannosaurs

Go to this episode on rnz.co.nz for more details

They can hunt, they can fish, they build little nurseries for their babies. Oh and some of them also engage in a bit of sexual cannibalism. Claire Concannon goes on a nighttime stroll in Kirikiriroa Hamilton to meet some fascinating spiders, and learn all about the weird world of spider reproduction.

Simon Connolly has watched around 1100 hours of footage of male spiders being placed into plastic containers with females inside. Sometimes they mate. Sometimes they get eaten. But that's just how it goes. Spider sex can be a risky business.

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Simon is part of the invertebrate behavioural ecology lab at the University of Waikato, where he is working towards a PhD. His supervisor, Dr Chrissie Painting, is interested in the big questions around how and why different mating systems evolve.

Chrissie is figuring out what prerequisites you need for a mating system called monogyny to evolve. Monogyny is when males mate with just one female - a set up that bucks the 'classic' sexual selection theory that says that males of a species will generally tend to try to mate with as many females as possible to ensure the continuation of their genes.

When you get monogyny in different animals you tend to see particular sets of traits, such as females that are a lot larger than their male counterparts. You also sometimes see particularly weird behaviours around mating time, including sexual cannibalism, where the female might eat the male after mating.

To identify the evolutionary steps that might lead a creature down the monogyny mating system route, Chrissie is focusing on a group of spiders that seem to show remarkable variation in the mating systems they employ.

By studying the four Dolomedes fishing spiders that live in Aotearoa New Zealand, and adding this to findings from her collaborators overseas about other Dolomedes spiders, she hopes to unravel the web of traits and circumstances that leads to evolution of monogyny.

Listen to the episode to join Claire Concannon, Chrissie and Simon on a spider hunt in Kirikiriroa Hamilton, to find out about this remarkable group of spiders (some of whom can fish!), and hear how Chrissie hopes this research will add to our understanding of life on earth.

Research into the evolution of mating systems in Dolomedes spiders is supported by a 2022 Marsden Fast-Start Grant awarded to Dr Painting. The project is in collaboration with researchers at the University of Nebraska-Lincoln, the National Institute of Biology in Slovenia and with Dr O'Neale at the University of Auckland.

To learn more: …

Go to this episode on rnz.co.nz for more details

With the Bug of the Year 2023 competition coming to the closing stages, it's not surprising that things are getting heated. In this breaking news story we learn how voting preferences have caused a rift in the Painting lab.

With the inaugural Bug of the Year competition coming to the closing stages, it's not surprising that things are getting heated in some corners.

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In this bonus audio, Claire Concannon talks to Chrissie and Simon about who they are voting for, who the dark horse contenders might be, and how the competition might help our native insects and spiders.

Make sure to listen to the full episode this week to find out all about Chrissie and Simon's research into the Dolomedes spider group.

Go to this episode on rnz.co.nz for more details

What do marine biologists get up to? Some Evans Bay Intermediate school students are learning all about it at the Victoria University Coastal Ecology Lab. Claire Concannon tags along to listen in, and to catch up with Professor James Bell to learn more about his research on sea sponges.

Shouts of surprise and excitement ring through the foyer of the Wellington University Coastal Ecology Lab. Four intermediate school students, with virtual reality headsets on, armed with controllers, are diving in to the ocean to count fish and lobsters.

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They are here for a tour of the lab, and to learn about what marine biologists do. "It's not just swimming with whales and dolphins," says Professor James Bell. As part of the presentation to the Evans Bay Intermediate students he introduces the subject of his research: sea sponges.

Because they can be found quite deep in New Zealand waters, he and his team will often use a remotely operated vehicle (ROV) equipped with a camera to survey for sponges. The most surprising finding for him in his years of research is just how abundant they are.

James and his group are interested in what role they play in the underwater ecosystem. By filtering nutrients out of the water and converting them into 'sponge poo' they might enrich the local area, helping other living things thrive in these sponge gardens.

But just as they are starting to understand the role that these sponges might play, it seems like they could be in trouble. After advocating for many years that sponges might in fact be climate change winners, James now qualifies that to tropical sponges only. Extreme ocean temperature events across the last few years have led to some dramatic sponge bleaching in New Zealand's temperate waters.

Looking to the future, James hopes to better understand why some sponges do okay in these warming waters, while others struggle. And he hopes that school group sessions at the marine ecology lab will inspire the next generation of marine biologists to continue this work.

Listen to the episode to learn more about the secret life of sea sponges, and to tour the Wellington University Marine Ecology Lab with James and his colleague Dr Alice Rogers.

To learn more:

As James said in this episode, evidence for a time indicated that sponges might do okay in our changing climate, he spoke to Alison Ballance in 2016 about this.

The mass sea sponge bleaching was reported on Morning Report in June 2022.

James and colleagues published a paper on the bleaching event in December 2022, and wrote a piece for The Conservation.

Go to this episode on rnz.co.nz for more details

Claire Concannon investigates how luminescence and specialised materials could be key to our growing data storage needs, and visits a test site for native vertical gardens that could cloak the walls of Wellington's city buildings.

More of us are making use of 'the cloud': we press save, and our precious photos, documents and data are stored, somewhere. But behind this ethereal shopfront is the physical reality of data storage, and its ever-growing needs.

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The future of long-term data storage

Optical storage discs such as CDs and Blu-ray had their heyday in the 90s. But they were quickly surpassed in terms of capacity by electromagnetic data storage on hard drives or solid-state drives.

However, these drives have a short shelf-life: they must be replaced every 5-10 years or else data will be lost. Many also require power, contributing to data centres' estimated consumption of 1-3% of global energy use.

The ideal then, is a form of long-term data storage that is easy to write and read, can hold a lot of data, is stable across a long time, and doesn't require constant power.

Robinson Research Institute scientist Dr Joe Schuyt thinks that using luminescence to encode data into specialised materials might be the key to our growing data storage needs. Listen to hear how a blend of reading, thinking and chemical tinkering might help him figure it out.

Greening our cities

Singapore is one of the most densely populated cities in the world, but also one of the greenest and most biodiverse. By law, developers must replace any natural area they develop with green space somewhere on the buildings. This means that plants are installed on roofs and drip from the walls.

Should we be doing the same for our urban environments here in Aotearoa? And which plants would actually cope on windy Wellington walls?

Victoria University of Wellington architecture PhD candidate Maggie McKinnon is testing whether native plants can hack it in a green wall set up in the city, as well as checking to see if there are benefits for local residents - including the feathered kind.

To learn more:

In 'Biodiversity and the city', researchers in the People, Cities and Nature research programme talk about the potential and challenges of wilding our urban spaces.

Listen to 'The details behind the data' by Damian Christie for a deep dive into how scientists make sense of data.

Go to this episode on rnz.co.nz for more details

In the final instalment of our summer science series, we bring you two stories from the ocean. First we have a story on marine noise pollution from Victoria University of Wellington Centre for Science in Society student, Xanthe Smith. Then, we have an episode on pāua from RNZ podcast Voices, presented by Kadambari Raghukumar.

In the final instalment of our summer science series, we bring you two stories from the ocean. First we have a story on marine noise pollution from Victoria University of Wellington Centre for Science in Society student, Xanthe Smith. Then, we have an episode on pāua from RNZ podcast Voices, presented by Kadambari Raghukumar.

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Sounds under the sea

Beneath the ocean surface, you might expect to find quiet. Instead, you'd hear a symphony of dolphin clicks and whistles, the snap-crackle-pop of shrimp, and grunting fish. You'd also hear the loud thrum of boat engines - an unnatural addition to the sea's soundscape.

These human-produced noises are causing problems for our ocean-dwelling neighbours - a phenomenon called noise pollution.

In this story, Xanthe takes us underwater to learn about the impacts noisy boats and machinery are having on animals like dolphins. She speaks to Dr Deanna Clement from the Cawthron Institute and Dr Matt Pine, a marine scientist specialising in acoustics and vibration.

Xanthe also takes a trip aboard Wellington's new electric ferry, and chats to skipper Mark McCormack. Compared to conventional vessels powered by fossil fuels, the electric ferry is much quieter. Could switching to electric help undersea animals?

Thank you to Dr Deanna Clement, Dr Matt Pine and Mark McCormack. This episode was produced by Xanthe Smith. Sound credits: Outboard motor, Tom Kieckhefer (CC BY-NC 4.0); harbour comparison, NC State University; New Zealand bigeye grunts, Craig Radford University of Auckland; snapping shrimp, Paul Perkins, NUWC Engineering; sea urchin/kina, Craig Radford University of Auckland (CC BY-NC-ND 4.0); common dolphin, Tom Kieckhefer (CC BY-NC 4.0); humpback whales, Tom Kieckhefer (CC BY-NC 4.0).

To learn more:

Alison Ballance listens to the underwater songs of Weddell seals in this episode of the award-winning series Voices from Antarctica

Matt was interviewed for this 2021 piece on the need for controls on underwater noise

Deanna featured in a recent episode of the Voices podcast

Passion for pāua …

Go to this episode on rnz.co.nz for more details

We continue our summer science series with an episode from RNZ's The Aotearoa History Show. In the first episode of season two, the show burrows into the story of rabbits and other pests introduced to New Zealand.

We continue our summer science series with an episode from RNZ's The Aotearoa History Show. In the first episode of season two, the show burrows into the story of rabbits and other pests introduced to New Zealand.

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We don't really know who first introduced rabbits to Aotearoa. But what started out with plenty of (h)optimism has led to generations of damage to our environment and economy.

In this episode, we learn why those initial introductions led to a rabbit boom, and how rabbits impacted both the land and farmers.

Since the population explosion, we've been looking for ways to control rabbits. In the 19th century, some took up the profession of "rabbiting" - trapping and poisoning the pests for a living. Eventually, some looked to introduce rabbit predators such as ferrets, stoats and weasels - a decision that would prove disastrous for Aotearoa's wildlife. In more recent times, we've turned to toxins (like 1080) and viruses (like calicivirus) to attempt to control our rabbit problem. But the rabbits are still here, and still threatening New Zealand's environment and economy.

This episode also explores the introductions of other animal species by both Māori and Europeans, and explains the ideology of many early colonists that Aotearoa needed to be "improved" through the introduction of exotic animals.

Learn more:

In addition to the podcast format, this episode is also available as a video

Episode one of the Fight for the Wild series looks at the devastating effect introduced mammals have had on New Zealand's unique wildlife

In 2016, Alison Ballance learned how rabbits and redbacks are threatening a rare native beetle

Go to this episode on rnz.co.nz for more details

As part of our summer science series we bring you an episode of The Otago Chronicles podcast, hosted by Max Balloch. In this episode, Max talks to Associate Professor James Scott from the University of Otago Department of Geology about looking up at the night sky and the hunt for what would've been New Zealand's 10th meteorite.

Our summer science series continues this week with an episode of The Otago Chronicles podcast, hosted by Max Balloch. In this episode, Max talks to Associate Professor James Scott from the University of Otago Department of Geology about looking up at the night sky and the hunt for what would've been New Zealand's 10th meteorite.

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At a few dozen schools across New Zealand, special cameras are keeping watch for meteors streaking across the inky darkness. They're part of a network called Fireballs Aotearoa - detecting meteors and connecting schoolkids to the night sky - established in early 2022.

Most meteors - space rocks usually originating from the asteroid belt - burn up as they fly through the atmosphere, dying in a blaze of glory. A handful might make it to the Earth's surface intact.

On 28 August 2022, three of the cameras picked up a fireball - an especially bright meteor that "winks out" just above the ground. "We couldn't believe that it had landed right in the middle of our camera network, that we'd just deployed," says James.

The meteor's trajectory was calculated, narrowing its potential point of impact to a farm west of Outram in Otago. Once a meteor touches the Earth's surface, it's known as a meteorite.

A two-day meteorite hunt ensued - about 100 students, researchers, and volunteers scoured the countryside for what would be New Zealand's tenth meteorite.

Listen to the episode to hear what they did (or didn't find) and learn about the science of meteorites.

Thank you to Associate Professor James Scott. This episode was produced by Max Balloch. Music credits: LEMMiNO - Cipher CC BY-SA 4.0; LEMMiNO - Nocturnal CC BY-SA 4.0; LEMMiNO - Cosmic Solitude CC BY-SA 4.0.

To learn more:

Claire heads on another meteorite hunt on the West Coast in this episode of Our Changing World

James spoke to Kathryn Ryan on Nine to Noon about Fireballs Aotearoa in July 2022

RNZ covered the Otago meteorite hunt including the initial footage, the two-day hunt, and the aftermath

Another meteorite streaked across the sky above Northland in November 2022, sparking another hunt

Go to this episode on rnz.co.nz for more details

Two stories about genetics produced by students at the University of Otago's Department of Science Communication. Amanda Konyn investigates whether gene editing has a role in future pest control, while Richard Marks explores why the "eat less, move more" approach to weight loss isn't really working.

Each year, science communication students at the University of Otago's Department of Science Communication are tasked with producing a podcast on a controversial science topic. In this episode, we hear two of those stories - on weight loss and gene editing - from Amanda Konyn and Richard Marks.

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Is there a future for gene editing in pest control?

In 2016, the then-government announced the "moonshot" goal to make New Zealand Predator Free by 2050. It's an ambitious project that aims to remove three of the biggest threats to New Zealand's native flora and fauna: rats, stoats, and possums.

However, current pest control methods are not likely to be enough to get us there. We need to develop new technologies in order to eradicate pests from Aotearoa. The technologies being considered includes types of genertic engineering (GE): gene editing and gene drives. But, given New Zealand's GE-free stance, is there a path forward for this kind of technology? And if so, who gets to decide whether it's appropriate to use?

To understand how gene editing might be able to help in the war against pests, science communication student Amanda Konyn speaks to Anna Clark, a PhD candidate and geneticist at the University of Otago. While conventional methods of pest control can remove up to 90% of pests from an area, the remaining 10% are particularly problematic to eradicate. As Anna puts it, "We just can't seem to get rid of them." It's this 10% that could be targeted by genetic pest control.

But even if rigorous testing and research shows that gene drives would be safe and effective for pest control, we may not roll out the tech beyond the lab walls. While scientists may champion the technology, ultimately, the decision to use gene editing (or not) will rest with the public and with mana whenua. Amanda chats to biodiversity and pest control expert Tame Malcolm (Te arawa: Ngāti Tarāwhai, Ngāti Pikiao, Ngāti Ngararanui, Ngāti Whakaue) about possible te ao Māori views on gene editing, and, why it's vital for Māori to be consulted.

Thanks to Anna Clark and Tame Malcolm. Produced by University of Otago Department of Science Communication student Amanda Konyn. Music by Blue Dot Sessions (CC BY-NC 4.0).

To learn more:…

Go to this episode on rnz.co.nz for more details

MethaneSAT is the first New Zealand government funded space mission. A joint project between the United States' Environmental Defense Fund and New Zealand, the project will see a methane sensing satellite launched into orbit. Science journalist Peter Griffin finds out why and how.

MethaneSAT - the first NZ-government-funded space mission - is launching a satellite that will detect emissions leaking from pipelines, agriculture, landfill and wetlands.

Science and tech journalist Peter Griffin finds out why and how.

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The recent COP27 climate summit focused on reducing carbon dioxide emissions with the aim of limiting global temperature increase to within 1.5 degrees Celsius.

Reaching that goal will also require a dedicated effort to reduce methane.

"Ultimately there's no way to have anything like a habitable world without tackling our CO2 emissions," says NIWA's Dr Sara Mikaloff-Fletcher, the leader of the MethaneSAT project at the Crown research institute.

"However if you are thinking about... how you can reduce emissions quickly, there's a strong argument to be made for including methane in that first tranche of work. Over the next 20 years, methane that we emit today is going to warm the atmosphere 85 times as much as the equivalent amount of CO2."

Short-lived but powerful

Methane is a powerful but short-lived greenhouse gas that scientists estimate accounts for about half of the net rise in global average temperature since the pre-industrial era. But methane emissions from oil and gas have been underestimated for years, due in part to a lack of independent monitoring.

A voluntary global effort, the Global Methane Pledge, was launched in 2021 to address the methane issue, with over 100 countries, including New Zealand, undertaking to reduce methane emissions by 30% on 2020 levels by 2030.

Some satellites currently track methane emissions but are unable to zoom in and identify their exact source. MethaneSAT aims to fill that gap.

Primarily funded by the US-based nonprofit Environmental Defense Fund, which is spending over $100 million on the project, MethaneSAT is also New Zealand's first government-funded space mission, to the tune of $26 million.

While the satellite will primarily be used to pinpoint methane emissions from leaky oil and gas pipelines around the world, New Zealand's involvement will allow a secondary focus on methane emissions from agriculture - sheep and cows here in New Zealand, but also rice paddy fields, wetlands and animal herds in the developing world…

Go to this episode on rnz.co.nz for more details

The kākerōri or Rarotongan flycatcher is a South Pacific conservation success story. Once reduced to just 29 birds, it has been rescued from the brink of extinction by a rat control programme managed by the land-owners of the Takitumu Conservation Area in the Cook Islands. Alison Ballance visits to find out more.

The delightful little kākerōri, or Rarotonga flycatcher, has been brought back from the brink of extinction in a Cook Islands conservation success story.

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In the mid-1980s New Zealand ecologist Rod Hay identified the critically endangered kākerōri as one of the Top Ten most at-risk birds in the Pacific. The population hit a low of just 29 birds in 1989, and Rod and fellow kiwi Hugh Robertson identified ship rats and feral cats as significant threats to the species' survival. "Rats ... are the number one problem for kākerōri," says Hugh.

They started a rat control study, using poison baits to knock down rat numbers and Hugh says the results were impressive.

"We found that the breeding success was 62 percent in the areas where we'd been controlling rats, compared with 26 percent in the areas we hadn't."

Female kākerōri are particularly vulnerable to being predated as they spend most time on the nest.

"In the non-treatment area 34 percent of the females died each year, but in the treated area we reduced that down to just 8 percent dying each year," says Hugh.

Kākerōri live in three forested valleys collectively known as the Takitumu Conservation Area, which lies in Rarotonga's southeast. The TCA, as it is known locally, belongs to three land-owning families. Back in 1996, they set aside 155 hectares of forest to protect the kākerōri.

The rat control programme was extended across the Takitumu Conservation Area, and has been led since 1999 by Ian Karika. Ian, other landowners and a team of volunteers put out poison baits from September to December each year, to protect nesting birds. The bait is funded by income from guided walks into the sanctuary.

The kākerōri population has climbed steadily and on his recent trip to colour band individual birds and conduct a population census, Hugh and his colleagues estimated that the kākerōri population has reached at least 621 birds on Rarotonga.

"It beggars belief really that they could have done so well, from being just 29 birds 33 years ago," says Hugh.

Hugh says the success of the kākerōri conservation programme on Rarotonga is due to the people who put out the rat poison…

Go to this episode on rnz.co.nz for more details

If the future of healthcare is personalised genomics, how can we ensure that it is used to lessen inequities, rather than strengthen them? This week, Our Changing World speaks to two of the co-leaders of the Rakieora programme - a pilot to develop a New Zealand-specific national database for genomic research.

If the future of healthcare is personalised genomic medicine, how can we ensure that genomic data can be used to reduce health inequities, rather than double down on them?

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For Associate Professor Phillip Wilcox from the University of Otago, empowering Māori to develop and lead indigenous genomic databases and genomic research can go some way to achieving this.

Phillip is one of the co-leads of a Genomics Aotearoa programme of work called Rakieora. The goal is to set up an infrastructure that allows the safe acquisition, storage and use of genomic and health data here in Aotearoa. One that upholds tikanga, centres the research needs of the community and minimises negative outcomes.

To pilot Rakieora, the team have looked at two ends of the healthcare spectrum - primary care in rural Tairāwhiti, and tertiary care of cancer patients in urban Tāmaki Makaurau.

It's the latter that is the focus of Professor Cris Print of the University of Auckland. "Our research is really around understanding how tumours can evolve and resist therapy, and really understanding what's the best way for us to implement some of this knowledge about tumours in the clinic," he says.

While initially a pilot, they hope that Rakieora will eventually be scaled up to allow national collaborative research into genomics.

Phillip is also involved in the Aotearoa Variome project, the aim of which is to add to our knowledge of the natural variation in genomes by sequencing Māori genomes. This will help address the current bias in genomic databases towards people of European ancestry and identify specific variations important for Māori healthcare.

Listen to the episode to hear Phillip and Cris discuss their work developing Rakieora, and what the future of genomic research in Aotearoa might look like.

To learn more:

Listen to last week's episode - Genome sequencing and the pandemic

We also discussed inequities in healthcare research in Business not as usual for heart health

The Detail podcast have an episode about filling in the final pieces of the human genome puzzle

If you want to learn more about DNA, genes, RNA and gene expression, listen to A new way to make vaccines

Go to this episode on rnz.co.nz for more details

Genome sequencing has become a household term during this pandemic. This week, we explore how it became an important tool in the fight against Covid-19.

We've become familiar with a whole suite of words and their meanings over the last three years of this pandemic - coronavirus, variant of concern, mutation. There is one term in particular that many of us probably wouldn't have come across as part of our daily lives before: genome sequencing.

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It wasn't all that long ago that genome sequencing of a whole virus genome was expensive, laborious and time consuming.

But rapid advancements in genome sequencing technology in the last decade have reduced the cost and effort involved. So, when a new disease emerged in late 2019, the technology was ready to be used in a new way, says Dr Jemma Geoghegan, a virologist at the University of Otago and ESR. "It completely revolutionised genomics. I mean, never before has real-time genomics been integrated at the level it is at the moment with disease outbreak," she says.

Jemma is part of a team of scientists at ESR, the Institute of Environmental and Science Research, that did early work on sequencing the Covid-19-positive cases that arrived in New Zealand. From there, they made a case for this type of real-time sequencing work to be integrated into New Zealand's pandemic response, to help guide decision making.

The extent to which genome sequencing was used here in the early days of the pandemic meant that Aotearoa could do investigations that other countries simply weren't able to undertake. According to Dr Joep de Ligt, Bioinformatics and Genomics Lead at ESR, "That actually has meant that we could do some fairly unique studies of actually showing airborne transmission during flights and in quarantine facilities.

"And they were the type of studies that were quite important to the recognition of the airborne nature of the virus," he adds.

In this Our Changing World episode, we learn how New Zealand's genome sequencing efforts added to global knowledge of the virus, and explore the past, present, and future of genome sequencing technology.

To learn more:

Dr Jemma Geoghegan's research into virus evolution was the focus of the episode Investigating the virosphere

The Detail podcast have an episode about filling in the final pieces of the human genome puzzle

If you want to learn more about DNA, genes, RNA and gene expression, listen to A new way to make vaccines

Go to this episode on rnz.co.nz for more details

Sunfish are the world's largest bony fish species - and yet scientists know little about their lives. This week, Our Changing World meets a sunfish researcher unravelling mola mysteries and dives into the weird world of sunfishes as a museum specimen is examined and prepared.

When you first see a sunfish - also known as a mola - your first question might be: how on earth can that thing swim?

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In fact, sunfish are pretty good swimmers, according to Dr Marianne Nyegaard, research associate at the Auckland Museum. They're also impressive in stature and are the world's largest bony fish, weighing up to 2.7 tonnes and measuring more than 3m long.

Yet, these hefty ocean-dwellers often end up washed up on beaches around the world, with no signs of illness or injury.

That's exactly what happened to a young sunfish I found in May this year, it was dead and stranded on a tidal mudflat about an hour and a half north of Auckland.

The specimen was fresh (no fishy smells here) and its good condition meant the Auckland War Memorial Museum were keen to add it to their collection.

I joined Marianne in a lab at the museum to inspect the juvenile sunfish and try to uncover its scientific secrets.

Until recently, there were two known Mola species: Mola mola, the common ocean sunfish, and Mola alexandrini, the bump-head or giant sunfish.

But during Marianne's PhD, she decided to follow up on genetic clues that indicated a mysterious third species might be lurking in the waters around Australia and New Zealand.

Her worldwide detective hunt led her to Birdlings Flat near Christchurch, where a sunfish with a peculiar-looking backside had washed up, and to the foyer of the Otago Museum, where a huge sunfish specimen has been on display for the last 50-odd years.

Marianne's efforts resulted in the identification of a new species, Mola tecta, or the hoodwinker sunfish. It had been hiding in plain sight for 125 years.

But there are plenty more sunfish secrets to unravel - such as, how do they grow from teeny larva that could fit on your thumbnail, into multitonne giants the size of a car? What do they eat? And how can you tell the three species apart when they're young?

That's where the sunfish I found comes in - as a juvenile Mola alexandrini, this specimen is one puzzle piece in the ongoing Mola mystery.

Listen to the episode to dive into the weird world of sunfish and hear what Marianne's investigations of the mini-mola revealed.

To learn more:

Check out Marianne's Ocean Sunfish Research Facebook page …

Go to this episode on rnz.co.nz for more details

Summer is on its way, and this week we're exploring both the power and the peril of the sun. First, we visit the Ultrafast Laser Lab to learn about efforts to create better solar panels. Then, we hear about one professor's quest to teach kids about sun safety using an ultraviolet dosimeter you can wear on your wrist like a watch.

The sun, our closest star, is an incandescent ball of plasma powered by nuclear fusion, flinging energy off into space. As Earth's tilted orbit brings the southern hemisphere more into the sun's direct glare (summer is coming!), we bring you two stories about harnessing that energy and protecting ourselves from its harm.

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New solar power materials

A long bench wraps around a laser at the centre of the room. It's crammed full of lenses, mirrors and prisms - the tools of the trade for a scientist investigating the physics of materials, like Dr Michael Price.

Here at the Ultrafast Laser Lab at Victoria University of Wellington's Kelburn campus, Michael runs tests on different materials, as he tries to find the next breakthrough for better, cheaper and more efficient solar power.

The quest to harness the sun's energy began in the mid-1880s with the discovery of the photovoltaic effect. Today, it has advanced to the large, crystalline silicon solar panels we see on roofs. But there's a limit to the efficiency of these silicon solar panels, and Michael wants to take it the next step.

"If we could harvest more of the infrared, more of the ultraviolet, that would be one way that we could up that efficiency limit. And some of the materials we're looking at can help with that," he says.

In particular, Michael and his colleagues have been studying an organic molecule called Y6, which he thinks might be the key for that next breakthrough.

Teaching sun safety

While we can harness the sun's rays to provide renewable energy, those same rays can be dangerous if they're directed at our skin instead of solar panels.

Exposure to the sun's ultraviolet (UV) rays can lead to skin cancer like melanoma. New Zealand's rates of melanoma are among the highest in the world and in 2020, Aotearoa had the highest death rate from melanoma out of any country.

Already this year, UV level readings are higher than normal, possibly due to the Tongan volcanic eruption in January.

For a nation that loves to get outdoors and soak up the sun, we need to get smarter about our sun safety. …

Go to this episode on rnz.co.nz for more details

Behind the scenes at the Auckland War Memorial Museum, a "menagerie" of specimens is a treasure trove for curator Dr Matt Rayner, who is researching how the Hauraki Gulf's seabirds are faring using clues from very old feathers.

"A menagerie" is how curator Dr Matt Rayner describes the land vertebrate collection in the backrooms of the Auckland War Memorial Museum.

There's a horse's head, stuffed peacocks sitting on a workbench, and the back corridor is filled with large specimens - moa, emu, and ostrich as well as reindeer, caribou and rhinoceros heads and skeletons.

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We're most familiar with museum galleries: carefully curated spaces, designed to tell stories. Precise taxidermy allows animals to stand or perch as they would in real life.

But in most museums, these front-facing displays are only a tiny percentage of the collections they house. Behind the scenes, there's a lot more going on.

As a curator, Matt works on public displays - but he also has his own area of research: seabirds.

For a recent project, Matt wanted to know: what's happening to the seabird residents of Tīkapa Moana the Hauraki Gulf across time? It's a tricky question to answer given that seabirds haven't been particularly well studied over a long period of time.

"Many of our land birds have been counted for decades, whereas we're just catching up with seabirds," he says. So, in the absence of long-term data, Matt and his colleagues turned to the backroom specimens held at museums for clues.

Matt scoured the collections at Auckland Museum, Te Papa Tongarewa, and Canterbury Museum for five seabird species found in the Hauraki Gulf: kāruhiruhi / pied shag, pārekareka / spotted shag, kororā / little penguin, tara / white-fronted tern, and tarāpunga / red-billed gull.

He focused on specimens collected from the Gulf over the years, all the way back to the 1880s. Then, he sourced feathers from his chosen specimens.

Matt also collected feathers from contemporary live birds during fieldwork in the Gulf, assembling a timeline of seabird feathers stretching from the 1880s to now.

Matt analysed certain elements in the chemical makeup of the feathers using stable isotope analysis. Looking at the stable carbon and nitrogen isotope signatures from these feathers can give Matt general insights into what the birds were eating and where they were living when the feathers were grown.

The nitrogen isotope analysis didn't indicate much change in the types of food these birds were eating (such as fish or crustaceans and squid)…

Go to this episode on rnz.co.nz for more details

How do you drill through 600m of thick Antarctic ice? Using hot water, of course. In this episode from the 2020 series Voices from Antarctica, Alison Ballance joins researchers hoping to solve the puzzle of why a giant river of ice has stalled.

It's a slow-moving stream of Antarctic ice across West Antarctica, that feeds the world's largest floating ice shelf.

So why has the Kamb Ice Stream been stalled for the past 170 years?

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It's a puzzle researchers are trying to solve in this episode of Voices from Antarctica, produced by Alison Ballance. This is the last episode we're replaying from the award-winning 2020 series in this mini-rerun.

The ice stream goes through periods of flowing and stopping, but as climate change intensifies, it's important to figure out what this means for the ice - and us - in a warming world.

To figure out what's happening, the team are using a hot water drill to access the liquid seawater and seafloor beneath the Ross Ice Shelf, which is 600m thick.

Listen to the full episode to dive beneath the ice.

Thank you to Liz Garton for help with this episode.

Learn more:

Read Alison's story from the original episode that first aired in 2020.

Find all the Voices from Antarctica episodes here.

Go to this episode on rnz.co.nz for more details

Weddell seals have returned to breed near Scott Base in Antarctica after a decades-long absence. On land, they're blubbery lumps. But underwater, they're graceful dancers and ethereal singers. A team of scientists is finding out more about the under-ice lives and habits of Weddell seals. Alison Ballance joins them in this episode from the award-winning series Voices from Antarctica.

Dive beneath the sea ice in Antarctica and you might hear the ethereal echoes of Weddell seals - a symphony of space sounds and jungle noises that carries for kilometres in the cold dark water.

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On ice, they're blubbery blobs. But underwater, Weddell seals are gloriously graceful swimmers.

They are the southernmost breeding and living mammals in the world, and in this episode, Alison Ballance accompanies scientists as they study a small population near Scott Base. The seals have recently returned to the area to breed, after historic hunting to feed huskies drove them out of the vicinity of the base.

So how are the local seals faring? Is the recently established Ross Sea marine protected area benefitting Weddell seals? Where are they heading to find a feed? These are the questions the NIWA-led team are investigating using high-tech data loggers and video cameras.

Listen to the full episode to fully submerge yourself in the Weddell seals' world.

Thank you to Liz Garton for help with this episode.

Learn more:

Read Alison's story from the original episode that first aired in 2020.

Find all the Voices from Antarctica episodes here.

Go to this episode on rnz.co.nz for more details

A team of NIWA scientists eagerly awaits the return of 19 emperor penguins carrying high-tech data loggers and video cameras. What will the data captured reveal about the penguins' secret lives at sea?

The emperor penguin mums and dads of Cape Crozier are returning from their fishing trips, bringing back full bellies - and some, treasure troves of scientific data.

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A team of NIWA scientists camped out at Cape Crozier equipped 19 penguins with data loggers, and five with video cameras, hoping to capture clues about where the penguins go to forage, and what they might be eating.

This week we're continuing our rerun of the award-winning 2020 series Voices from Antarctica, produced by Alison Ballance. In this episode, Alison sits down with penguin researcher Gitte McDonald to look at the data from a recently returned emperor penguin.

It turns out, each individual penguin travels out to quite different parts of the pack ice, swimming 250km from the colony, and making dives as deep as 400m over more than two weeks. During these trips, an adult bird can pack on up to 2kg in body weight.

Listen to the full episode to learn more about the secret lives of these remarkable ice-dwellers.

Thank you to Liz Garton for help with this episode.

Learn more:

Read Alison's story (and check out her photos!) from the original episode that first aired in 2020.

Find all the Voices from Antarctica episodes here.

Go to this episode on rnz.co.nz for more details

Revisit the frozen continent with us in this mini rerun of the Voices from Antarctica series. This week, Alison visits Cape Crozier to meet a colony of emperor penguins and the team of scientists studying them.

Emperor penguins spend part of the year huddled together on the ice, keeping eggs and then chicks warm. But where do they go once breeding season is over?

Follow Our Changing World on Apple Podcasts, Spotify, Stitcher, iHeartRADIO, Google Podcasts, RadioPublic or wherever you listen to your podcasts.

This week we're starting a mini rerun of Alison Ballance's award-winning 2020 series Voices from Antarctica. We're starting with episode four: after travelling south to the frozen continent in a Hercules aircraft and visiting Scott Base, Alison is now at Cape Crozier in Antarctica to meet the resident emperor penguins - and the scientists studying them.

Here, a team of NIWA researchers is hoping to unravel the emperors' secret lives at sea using data loggers.

Thank you to Liz Garton for editing help.

Learn more:

Read Alison's story (and check out her photos!) from the original episode that first aired in 2020.

Find all the Voices from Antarctica episodes here

Go to this episode on rnz.co.nz for more details

It's spectacularly spiky and delivers a painful or even deadly sting. Why are a team of conservationists growing and planting up Orokonui Ecosanctuary near Dunedin with more and more native tree nettle, ongaonga? It's all because of a pretty little pollinator called the kahukura, or red admiral butterfly, and its prickly preferences. Claire Concannon visits Orokonui to learn more about the ongaonga-kahukura relationship, as well as new research investigating whether these native butterflies are the victims of a sneaky ecological 'trap'.

With stems and leaves covered in sharp, needle-like spines, it's a native plant that screams 'don't touch me'.

And rightly so. If you do touch the native tree nettle ongaonga, the consequences can be painful - and even deadly.

Listen here

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Walking down the Butterfly Track at Orokonui Ecosanctuary just north of Ōtepoti Dunedin, you'll come across plentiful ongaonga, purposefully planted.

Why would we want more of this 'ferocious' plant that can deliver an unpleasant sting?

Part of the ecosanctuary's mission is to provide as many native species as possible with habitats and ecosystems, says botanist and educator Taylor Davies-Colley.

"A lot of species require very specific host species for their caterpillars to live on," he tells Our Changing World.

Native butterflies like the kahukura / red admiral rely on the sharp barbs of ongaonga (aka Urtica ferox), which provide a safe haven for their precious eggs and larvae.

As the caterpillar grows, it folds the spiky leaves around itself as a protective tent during the day.

University of Otago Master's student Greer Sanger has been researching how the kahukura's preferences may be leading the butterfly species into an 'ecological trap' - a situation where an animal inadvertently opts for a less-than-ideal habitat.

Dragonflies attracted by the shiny surfaces of black headstones because they resemble the surface of water are an example of this.

In the case of kahukura, could introduced nettles be swindling butterflies with the offer of inferior habitat?

To test this idea out, Sanger caught some kahukura from around Ōtepoti and placed them in special cages with either ongaonga, a Chatham Islands hybrid nettle, or the introduced dwarf nettle. She then watched to see where the butterflies chose to lay their eggs.

"They definitely had a preference for the native over the introduced ," Sanger says. "None of them chose to lay on the introduced nettle." …

Go to this episode on rnz.co.nz for more details

We're saying farewell to the Stratospheric Observatory for Infrared Astronomy (aka SOFIA) this month. The mission, which was partially based in Christchurch, wraps up after a decade of observing comets, stars, planets, and the moon. In July 2017, Alison Ballance boarded the Boeing 747 with a flying telescope for one of its research flights.

Last month, the SOFIA telescope left Ōtautahi Christchurch for the final time, heading for retirement in California. The Stratospheric Observatory for Infrared Astronomy (SOFIA) isn't your usual telescope: it's installed on a Boeing 747 jet plane with a hole cut in its side.

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Since 2013, the SOFIA telescope took off from Christchurch to cruise the clear southern skies and capture observations of comets, stars, and planetary atmospheres. Data collected by SOFIA contributed to the October 2020 finding of water on the surface of the moon.

As a send-off for SOFIA, which officially wraps up its mission on 30 September, we're replaying an episode from September 2017. Alison Ballance reports from aboard one of SOFIA's research flights.

See Alison's original story from September 2017

Go to this episode on rnz.co.nz for more details

In a future that is free of fossil fuels, where will we source all the products that we get from the petroleum industry? Scientists at the forest research institute Scion think that trees might provide the solutions we need.

Fossil fuels aren't just used for transport and energy - they're also used to make everyday products. As we move away from fossil fuels, where else can we find these materials? For the team at the forest research institute Scion, the answers can be found in our forests.

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"We need to strike the word waste from our vocabulary," says Dr Stefan Hill, the portfolio leader of high-value biorefineries at Scion. His team are responsible for figuring out what useful compounds can be extracted out of waste biomass - for example, the bark that is stripped from pine trees before they get shipped overseas as timber.

Bark is essentially the skin of the tree, key for its protection and defence. So the team are interested to see if they can extract antimicrobial and water repellent compounds for use in health and clothing applications.

Some of the work is at early stages, but one idea that has progressed to proof-of-concept stage is the extraction and use of vegetable tannins.

Chemist Dr Hilary Corkran works on the tannin extraction from pine bark in the lab. Working with Callaghan Innovation to upscale their extraction process, and in partnership with the leather and shoe research association (LASRA), they've been able to show that these tannins can be used to create a soft, good-quality leather product. In fact, with McKinlays footwear in Dunedin, they've produced the only pair of New Zealand-sourced tannin leather boots. Currently all tannins used in creating leather in Aotearoa are imported and the current most common method uses the heavy metal chromium. The team hope that their work will provide a locally sourced vegetable tannin product to change this.

Of course, biorefineries will only work if it is technically and economically feasible to extract the materials. That is where the work of Dr Marie-Joo Le Guen comes in. She collaborates with industry partners to essentially find a 'home' for the materials and compounds, and work on the upscaling of the extractions to make them worthwhile. …

Go to this episode on rnz.co.nz for more details

In a room in the Manaaki Whenua building in Auckland are rows and rows of shelves, with cardboard boxes containing an array of weird and wonderful dried fungi. Claire Concannon visits to learn how and why these specimens are kept, and finds out about its sister culture collection, which is helping in the defense against invading plant pathogens.

The New Zealand Fungarium has a library feel - a quiet and calm room, with just the hum of air conditioning as a backing track. On display in a glass fronted cabinet is a small group of mummified caterpillars on a stick, like weird larval lollipops.

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Ingesting a spore of a particular native fungus causes the caterpillar to change its behaviour, explains Dr Mahajabeen Padamsee, curator of the New Zealand Fungarium. "It goes and buries itself with its head pointing up, and the fungus grows from the top of the head," she says.

These 'vegetable caterpillars' are part of more than 100,000 specimens that make up this collection, a store of dried fungi housed in the Manaaki Whenua - Landcare Research building in the suburb of St Johns in Auckland.

A large climate-controlled room hosts row upon row of shelves, stacked with large cardboard boxes, themselves filled with envelopes containing dried fungi wrapped in tissue. Some of the specimens are just too large for envelopes, and rest instead in larger boxes or are wrapped in plastic bags to trap their spores.

Adrienne Stanton, the collection manager, is responsible for keeping the specimens safe and in good condition, as well as facilitating specimen loans to researchers. Alongside a huge number of native New Zealand fungi, the collection also contains many specimens from across the Pacific.

The New Zealand Fungarium is used for two main functions - investigating fungal biodiversity and helping biosecurity efforts. It grows each year by about 2,000 specimens. Some are given to the collection by researchers, but many are gathered during the annual Fungal Foray - a multi-day fungi treasure hunt, held in a new area each year with the Fungal Network of New Zealand.

An important part of the collection consists of 'type' specimens - individual specimens chosen to serve as exemplars, the physical basis for naming and describing a species.

Down the corridor from the Fungarium, there's a restricted access room filled with large, stainless-steel tanks. …

Go to this episode on rnz.co.nz for more details

Alison Ballance visits the Brook Waimārama sanctuary, and discovers that the old saying "many hands make light work" is particularly true when it comes to community conservation. A relatively new fenced sanctuary, the Brook Waimārama team is now at the exciting stage of bringing native wildlife back into the area, including orange-fronted parakeets - kākāriki karaka - and giant land snails.

Giant carnivorous land snails. New Zealand's rarest parakeets. And noisy tieke or South Island saddlebacks.

All three species are at risk from introduced predators - and all have recently been given a safe new home on the outskirts of Nelson, inside the Brook Waimārama fenced sanctuary.

The 690-hectare forested valley was once the water supply catchment for Nelson. These days it satisfies a different kind of thirst - for nature and community conservation.

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The Brook Waimārama sanctuary is surrounded by a 14.4 kilometre-long pest-proof fence that was constructed in 2016. In 2017, all introduced animals within the fence were removed; this included predators such as rats, stoats, possums and pigs, and browsing mammals such as goats and deer. In 2019 the sanctuary was declared pest-free. Mice have subsequently reinvaded, as they have in other fenced sanctuaries, and are a constant presence.

Occasionally, rats and weasels have managed to get back in but sanctuary staff and volunteers respond quickly, setting up networks of kill traps to catch the invaders.

Giant carnivorous land snails

In July 2022, 30 large land snails were released in the sanctuary.

The Powelliphanta hochstetteri consobrina snails were collected from two sites nearby, one a pine forest and the other native forest. Ten more snails from another site will be translocated later.

This is the first official translocation of a Powelliphanta species, and is possible because the subspecies is absent from the sanctuary but is clearly within its natural range.

This subspecies grows to about 5 centimetres across, and like all Powelliphanta snails is slow-growing and long-lived.

Powelliphanta snails hunt earthworms, which they slurp like spaghetti.

The snails will be left undisturbed for five years, when a search will be carried out to see if any small snails can be found, which will indicate that breeding has taken place.

Orange-fronted parakeets / kākāriki karaka

Orange-fronted parakeets or kākāriki karaka are New Zealand's rarest parakeet, with just a few hundred birds in the wild in North Canterbury…

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Claire Concannon catches up with Dr. Taniela Lolohea of Auckland University of Technology. He is researching in the relatively new field of low temperature plasma surface coatings, and explains how it can be used to create customised surfaces for many purposes. But he is also investigating ways to encourage more Pacific students in science, including by developing projects that might be more attractive for them.

Solid, liquid, gas, and plasma.

The fourth state of matter, plasma, makes up 99.9% of the known visible universe. Stars, lightning, our upper atmosphere: all made of plasma. And increasingly, scientists are figuring out how to harness the power of plasma for many different applications.

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Plasma is ionised gas - that is, gas that contains charged particles. It is the often-unseen factor in many manufacturing and processing steps of the goods that we buy and use, like our TVs, cellphones and computers. About one third of the steps involved in making microchips, for example, are plasma based.

Plasma etching, plasma welding, plasma bonding and cross-linking, using plasma to clean surfaces, or make them sticky, or sterilise them. The list of all the things we use plasma for goes on and on.

At the Auckland University of Technology, chemistry lecturer Dr Taniela Lolohea is focused on how plasma jet technology can be used to add thin, high quality, specific purpose coatings.

'Traditional' plasma technology involves heating a gas up to 100s or 1000s of degrees Celsius to create and maintain the plasma while it is being used for the coating, etching, bonding or other process. As a result, there are limitations in its use for adding surface coatings - for example, using something that been heated to a thousand degrees on plastic or certain textiles is just not going to work. Lolohea's research harnesses a recent development in this area which means that plasma can now be created and used at the relatively low temperatures of 25-60℃.

https://players.brightcove.net/6093072280001/default_default/index.html?videoId=6311313003112

This opens a world of opportunity that Lolohea is keen to explore. Working with collaborators he is problem-solving different surface coating needs - whether that is a coating that is thick, thin, porous, dense, antimicrobial, or needs to contain intact biological structures like proteins. …

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While we might have heard all we ever want to know about viruses in the last few years, the truth is, known viruses represent less than zero point one percent of the estimated total of viruses out there. Claire Concannon meets a team from the University of Otago trying to increase our knowledge of virus diversity, so that we can better understand their evolution.

All of us can list at least a few viruses. Probably more now than three years ago. Coronavirus, influenza, ebola, zika, chickenpox, monkeypox, human immunodeficiency virus (HIV) - there are plenty going around.

But the viruses we know about couldn't even be described as the tip of the iceberg when it comes to virus diversity. It's more like one frozen raindrop resting right at the top of an unfathomably giant continent of ice.

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"It's mind-blowing how many viruses we still have to discover, around like 99.99% of the virosphere is still to be discovered," says PhD student Stephanie Waller.

Waller is currently investigating native New Zealand species to figure out what viruses are associated with them. She is focusing in particular on tuatara, mokomoko (skinks and geckos), tuna (eels) and pekapeka (bats).

Waller's work on cloacal swab samples from tuatara from Takapourewa Stephens Island has already revealed potentially 50 new viruses. She is hoping this work will build on our knowledge of virus diversity and help us to figure out how viruses jump to new hosts.

That is the key question in disease emergence, according to Waller's supervisor and senior lecturer Dr Jemma Geoghegan, who says only knowing a tiny fraction of virus diversity and the hosts they associate with, limits our understanding.

Geoghegan has been a key member of the team of scientists behind sequencing Covid-19 cases to inform New Zealand's pandemic response. But before the pandemic, and alongside her research identifying variants, Geoghegan is very much focused on how viruses evolve.

" is really about trying to understand the diversity of viruses in nature to then understand the mechanisms behind virus host jumping and spread into new hosts," she says.

In Geoghegan's lab in the Department of Microbiology at the University of Otago, other researchers are specifically focused on disease-causing pathogen puzzles.

Such as, identifying the underlying pathogens causing two sicknesses in the endangered hoiho (yellow-eyed penguin). …

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Edin Whitehead inherited a love of birds from her father and became captivated by the majesty of seabirds on a trip to the Subantarctic Islands. Now a PhD student at the University of Auckland, she is trying to figure out how best to help the birds of the Hauraki Gulf, who are facing many threats, including warming waters.

Many of northern New Zealand's seabirds are out of sight and out of mind for most of us.

They live on the wing, migrating and foraging long distances across the open ocean. When they come to land to breed and rear chicks, they do so in remote coastal areas, or on small, uninhabited islands in Tīkapa Moana, the Hauraki Gulf. But these seabirds are under pressure.

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"They're the most threatened group of birds in the world," says Edin Whitehead, PhD student at Waipapa Taumata Rau University of Auckland. "They face threats at sea and on land, it's a double whammy."

Climate change, mammalian predators, plastic pollution, oil spills, fisheries bycatch, diseases, light pollution - the list goes on. Whitehead investigated them all for a 2019 report titled Threats to Seabirds of Northern Aotearoa New Zealand.

Putting together this report helped her identify some knowledge gaps which then guided the focus for her research.

Whitehead is studying four species of seabirds that breed in the Hauraki Gulf but travel different distances for migration - from long distance (rako, Buller's shearwater), to shorter (totorore, little shearwater, and tītī wainui, fairy prion) to the homebirds that don't tend to migrate (pakahā, fluttering shearwater).

Over the last three years she has visited islands in Tīkapa Moana where these birds breed. There, she assessed their health and foraging movements to see how both adults and chicks are doing during the intense period of chick rearing.

GPS tagging a subset of the birds has allowed Whitehead to get a glimpse into what areas of the ocean are important to them for finding food. On land, weighing the chicks, analysing their regurgitations or faeces, and sampling feathers to analyse for stress hormones, will give her an idea of how the feeding is going, and what the health of the colony is.

Now she is moving on to the analysis phase of her PhD - in the next few months she will line up the GPS tracking data with sea surface temperatures and extract the corticosterone stress hormone from the adult and chick feathers. …

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The Auckland University of Technology Living Laboratories project is all about investigating how best to grow back native forest. At Pourewa creek, this collaboration between AUT and Ngāti Whātua Ōrākei involves planting blocks with different nursery plants and measuring individual tree growth and biodiversity indicators over time. They hope to figure out the recipe to cheaper and faster regeneration of native bush.

We know that trees can help us sequester carbon and get us to our climate change carbon goals. We also know that native forests are spaces that can help native biodiversity.

So why are people lining up to plant large areas with pinus radiata instead of native ngahere?

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The answer is simple - many exotics, like pine, are lower risk, cheaper and faster to grow, sequestering more carbon in the short term.

Under the New Zealand Emissions Trading Scheme businesses have to surrender one emissions unit - one New Zealand unit - to the Government for each tonne of emissions they emit. Foresters who plant trees that absorb carbon earn units from the government that they can sell.

In a policy framework where carbon sequestration is valued in isolation of other benefits, native trees are at a disadvantage.

This is what the Auckland University of Technology (AUT) Living Laboratories project wants to help address.

It's a set of planting experiments designed to investigate the quickest, cheapest, most risk-free way of restoring native forests in a farmland context, as well as monitoring the ecosystem benefits such forest provides as it grows.

Left to its own devices much of the farmland in Aotearoa would, over time, return to native forest.

First, the pioneer plants would appear - for example, kānuka, mānuka, karamū, māhoe. Able to deal with drier, hotter conditions in open areas, eventually they would provide the cover for the next round of trees to move in - maybe pūriri, rimu, rātā, tōtara. Brought by seeds dispersed by wind or bird, maybe from the native bush nearby.

But this takes time. A lot of time.

Across three sites, the AUT Living Laboratory project is investigating different ways of fast-forwarding this natural plant succession to get to the later, bigger trees earlier.

The first site is on Ngāti Whātua Ōrākei land at Pourewa, where they are revegetating 2.2 hectares and comparing kānuka pioneer plants versus a mixed group of māhoe, ngaio, tarata and karamū…

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The most extreme places in Antarctica give rise to the toughest and weirdest types of life. From creatures living a very different chemical life to ours at underwater methane seeps to the secret tools bacteria use to keep their DNA safe from the harsh conditions of the dry valleys.

Antarctica is a continent of extremes. The coldest. The driest. The windiest. It pushes life to the very limits. Living things down there have evolved some weird and interesting adaptations, which researchers are still discovering.

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Microbial mats and methane

Descending through the ice on a dive in Antarctica, Dr. Sarah Seabrook was struck by how alien it looked, like she could have been diving on Europa, one of Jupiter's icy moons. The dark volcanic sediment at the underwater base of Mt Erebus brought a white fluffy mat into sharp focus, like snow scattered on the seafloor.

It was 2016 and this fluffy mat was the reason that Seabrook was there, diving in the area as part of her PhD research. Under the supervision of Dr. Andrew Thurber of Oregan State University, Seabrook was able to confirm exactly what it was - a mat of methane-loving microbes attracted to the area by a methane seep.

Methane is a gas - the main component of natural gas and a potent (albeit relatively short-lived) greenhouse gas. It can be produced by microbes on land that live in landfills, the soil, or in the stomachs of ruminants, like cows and sheep. But it is also produced when old organic matter is broken down by high temperatures and pressures in rock deep under the ground.

Methane seeps are what happens when this trapped methane reaches the seafloor surface and leaks out. These seeps support amazing and weird deep-sea habitats, the foundation of which are microbes that can make energy from methane, in the absence of light. Methane seeps are found at tectonic plate margins around the world, but their presence in Antarctica is poorly understood.

This is what Seabrook wants to investigate.

She has gathered further evidence of seeps and gas plumes in other areas of the Ross Sea that hint to a wider network. With another research trip to Antarctica planned in 2023, she's hoping to figure out the puzzle of methane seeps in Antarctica, and the weird living things that they support.

Dr. Sarah Seabrook's work at NIWA is supported by the Antarctic Science Platform and the New Zealand Antarctic Resilience initiative. Previous research discussed in this episode was supported by the National Science Foundation and Oregon State University in the United States.

DNA repair tools of extreme bacteria…

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The eruption of Hunga Tonga Hunga Ha'apai in January triggered a tsunami of unprecedented proportions, impacting the entire Pacific. How did this volcanic eruption lead to a tsunami detected across the globe, including as far away as the Mediterranean? Science communicator Ellen Rykers speaks to the scientists unravelling the secrets of this rare phenomenon.

The eruption of Hunga Tonga Hunga Ha'apai, just north of Tonga's main island, surprised scientists. The underwater volcano had erupted a few times in recent years - but only small, localised outbursts. What happened in January was on a whole other scale - blanketing the Tongan archipelago in ash, and sending tsunami waves across the Pacific.

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"When I heard about this one, I wasn't expecting anything near as big as what actually happened," says Dr. Emily Lane, a tsunami expert at NIWA.

The tsunami in particular was unprecedented: most tsunamis are caused by earthquakes, not volcanoes. Plus, those tsunamis that are caused by volcanoes tend to only have effects within a few hundred kilometres. But Hunga Tonga Hunga Ha'apai's waves radiated as far as Japan and South America, and tsunami activity was even detected in the Caribbean and Mediterranean. What made this tsunami go global?

Hunga Tonga Hunga Ha'apai's secret superpower lies in the air pressure shockwave it produced, which circled the globe. This shockwave supercharged the existing tsunami waves, giving them the energy and staying power to travel further than usual.

Plus, the air pressure wave can travel over land, allowing it to sweep across distant oceans like the Mediterranean and Caribbean, warping the sea surface and instigating detectable tsunami activity in these far-flung places.

But there are more complexities underlying volcanic tsunamis, and we don't understand them - or the risk they pose - particularly well.

Enter Dr. Colin Whittaker and his research team at the University of Auckland. In a warehouse filled with giant aquarium-esque tanks, Whittaker's team is unravelling the secrets of tsunamis generated by volcanoes.

One of the ways a volcano can make waves is through the sheer force of the explosion. This is what Dr Yaxiong Shen is investigating, by using a steam jet in a large tank to simulate an underwater eruption. By changing different parameters, Shen can figure out which conditions will lead to the biggest waves…

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With their antler-like mandibles, Helm's stag beetles often get stuck in to one another. But they are fighting a bigger battle too - against predators and habitat loss. PhD student Luna Thomas is studying these little known endemic insects. She hopes her work will add to our sparse scientific knowledge, and maybe help some of the other native stag beetle species, some of which are critically endangered.

This is a(nother) tale of a native New Zealand underdog, and the passionate people who study them. No flashy feathers, no YouTube livestream, no pretending to be something its not for the limelight. And yes, it too is battling predators and habitat loss.

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Meet the Helm's stag beetle, Geodorcus helmsi, so named because of their enlarged mouthparts, or mandibles, that look like stag antlers. In general, they are pretty chill, moving slowly through life. The spend their days in the soil and at night they find a favourite tree to climb up to sip some sap.

It's one of ten native stag beetles in the Geodorcus genus. It is also the most widespread - it has been found along the west and south coasts of the South Island - from Karamea in the north to Tapanui in the south and also on Rakiura Stewart Island.

Which is one of the field work sites for PhD student Luna Thomas' research. She wants to get a better understanding of the behaviour and size and gender distribution of these beetles. To do that, she has to go beetle hunting, at night.

On Rakiura Luna has a natural experimental set up - she can compare findings between the predator-free Ulva island and around the town of Oban. Unfortunately, in the latter, she is coming across the grizzly remains of rat predation - large caches of beetle heads.

Hopefully the recent announcement of Manaaki Whenua and Predator Free Rakiura's joint plan to remove predators from the island means a brighter future for the beetles there.

However, other species in this Geodorcus group are not so lucky. Some have only been found in very restricted habitat, the most extreme example of which is Geodorcus ithaginis or the Mokonhinau stag beetle. It had been restricted to one tiny offshore rocky stack, but couldn't be found in a 2019 survey.

As part of her research, Luna also has a DOC permit to bring some of the Helm's stag beetles back to the University of Otago, where she is trialling conditions to keep them in captivity. Though different species, she is hopeful that the information gleaned from Geodorcus helmsi may also help some of its critically endangered cousins.

To learn more:…

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The New Zealand data science programme, Taiao, aims to help researchers make sense of environmental data so they can make useful predictions to guide good decisions. Claire Concannon meets the team at the University of Waikato where the programme is hosted. And a group in the Auckland Bioengineering Institute are researching a new needle-free jet injector design that they think might lead to a happier future for those with needle phobia.

Every minute satellites and sensors all around Aotearoa are pinging information to servers, taking all kinds of measurements - images, temperatures, water flows, weather conditions, you name it.

For environmental researchers these data hold the clues for what is coming next, but when there is so much information, how do you make sense of it all?

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The data science programme TAIAO aims to help with this.

Led by the University of Waikato, the TAIAO team is developing new machine learning methods able to deal with large quantities of environmental data.

Funded by the Ministry of Business, Innovation and Employment to the tune of $13 million over seven years, the programme is building an open-source online framework to allow researchers to share machine learning algorithms, tweaks and datasets.

It's a collaboration across the Universities of Waikato, Auckland and Canterbury as well as engineering company Beca and MetService.

Environmental scientists, such as Professor Karin Bryan, help connect data scientists and data engineers to interesting New Zealand specific datasets and problems to tackle.

Then data scientists, such as Dr. Nick Lim, create and optimise machine learning algorithms to make relevant predictions, and then make these available online for other environmental researchers to use and adjust as they need.

In this way the TAIAO team aim to promote a vibrant community of environmental researchers sharing information aimed at getting reliable answers or predictions that can guide good decision making.

Needle-free injection research

For hundreds of years a needle and syringe has remained the best way to deliver drugs and vaccines. But for the needle-phobic, is there hope for a future respite?

Dr. James McKeage is working on it. He's a post-doctoral researcher at the Auckland Bioengineering Institute and wants to optimise drug delivery with a needle-free jet injector. The technology has been around for a while, based on spring loading or gas piston, but McKeage wants to perfect an electric motor driving model…

Go to this episode on rnz.co.nz for more details

PhD student Kiamaia Ellis describes crayfish as a vulnerable taonga species. Local iwi in Tauranga believe the crayfish population is decreasing because of urban, industrial and harvesting pressures. But Kiamaia is keen to be a part of the solution, so she's studying the resilience of pēpi kōura / baby crayfish. She wants to understand how these tiny species that take eight years to become an adult are able to thrive based on a kaitiakitanga or guardianship approach.

Inside the lab space at the Coastal Marine Field station Kiamaia Ellis checks in on the pēpi kōura, one is not much more than two centimetres in length.

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In another tank one is darker in shell colour and the other is more translucent, Ellis says it's because of how much light the kōura expose themselves to while in their tanks.

One pēpi is shy and only comes out when it's feeding time, the observation notes refer to it as the 'pipe cray'.

"I'm actually quite attached to the pēpi kōura...they're such characters there's one there that comes out and dances around and plays and we have a little kōrero" Ellis says.

Ellis' Phd research project 'Pēpi Kōura: A transdisciplinary mātauranga Māori and science approach to enhancement and resilience of puerulus kōura in a changing climate" stems from the aspirations of local tangata whenua who according to Ellis have 'observed the degradation of tāonga species over many generations'. Local iwi put this down to urban, industrial and harvesting pressures.

Te Kehu Butler has witnessed first-hand the impact commercial fishing has had at Mōtiti Island located sixteen kilometres north east of Tauranga. According to Butler the once abundant crayfish pataka kai (food resource) areas have all but disappeared. Butler is a seafood diver and argues that commercial fishing was another problem.

"Commercial fishermen would get a license and they would bombard the whole island...and they'd take all the crayfish it made It harder for us to feed the manuhiri at the marae at different occasions...so when they bombed the island like that the old people used to have to go out deeper to dive for crayfish" he says.

In 2013 Ellis spent some time interviewing her Kaumatua to understand the stories and customary knowledge about pataka kai. She's also drawing on the maramataka (Māori lunar calendar) to correlate the times of recruiting kōura from the harbour…

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Working with the community and local schools, the Karioi Project aims to turn the tide on biodiversity loss in their area. In recent years they've rallied around the grey-faced petrel, or Ōi, who they hope to help return to the maunga.

In the great cycle of nutrients between the ocean and the land, seabirds are an important link. Burrowing seabirds transport nutrients from the sea into the costal bush where they nest. But many are having a hard time on the mainland coast due to predators.

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This is the challenge that the ōi or grey-faced petrel in Whāingaroa Raglan is facing.

The bush-clad Karioi maunga, eight kilometers south-west of Raglan, is the most northerly forest on the west coast that connects all the way from mountain top to sea. In recent years the grey-faced petrel has been spotted digging burrows to nest along the coastline at the base of Karioi, but predators such as ferrets and stoats are taking a massive toll on both the chicks and adult birds.

This is what the Karioi Project team are taking action on.

What began as a small volunteer effort has grown to a project employing 12 people part time, including predator control rangers, educators, a backyard trapping hub coordinator, and a seabird ranger dedicated to monitoring the ōi.

Led by project manager Kristel van Houte, the aim is to protect the local biodiversity of Karioi, its ngahere, and the surrounding coastline. It focuses on predator control, both on the maunga and along the coast, with an emphasis ōi nest areas.

The ōi is an oceanic seabird, dark black-brown in colour, with grey feathers at the base of the bill and throat.

They are one of the few burrowing petrels to still survive on the New Zealand mainland, in small colonies scattered around the upper North Island coast. Larger colonies are doing well on predator free offshore islands.

In the Karioi team, Nic Callaghan is the seabird ranger responsible for the monitoring of the burrows. The birds will return in late Autumn, find their mate (they are monogamous), and breed, with an egg laid around mid-winter. The eggs hatch in August or September, with chicks fledging between November and January. At the moment the project is monitoring around 50 burrows, but the numbers of chicks fledging are consistently low, due to the impact of predators.

With an extensive education programme and backyard trapping hub, the team are working with the community to help restore this vital connection between the ocean and the land.

To learn more:

There are a number of Our Changing World episodes celebrating seabirds! Listen to:

More seabirds on Mana island…

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Two stories about the promise and perils of chemistry research. From a team recreating Renaissance beauty recipes in the hopes of rediscovering a 'miracle ingredient', to a researcher investigating New Zealand's deadliest synthetic cannabinoid.

Natural products are the origin of many of today's beauty products and medicines, with plant, mineral and animal product extracts analysed and then often re-made, or improved upon, in the lab.

Today we have one story about new discoveries from old recipes, and another about what can happen when this kind of chemistry goes wrong.

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The Beautiful Chemistry Project

When art historian Associate Professor Erin Griffey was invited to give a public talk on her research into Renaissance beauty culture, she thought some show and tell would be the way to go. Linking up with some of her University of Auckland colleagues in the chemistry department she pulled out a few old recipes and they started making a batch of 15th-century beauty products.

That was the birth of the Beautiful Chemistry Project - an investigation into Renaissance beauty recipes to discover the secrets they might hold.

Griffey's extensive research and cataloguing of Renaissance texts on the subject has provided a database of thousands of beauty recipes, including ingredients from the mundane, to the bizarre and sometimes even dangerous.

Since Senior Research Fellow Dr Michel Nieuwoudt got on board she has helped to support summer students in their investigations of some of the 'stickier' recipes. Those that, according to Erin's database, resurfaced numerous times across the decades and in different countries.

Using chemical and functional analysis the team are figuring out how these recipes work, and if there are compounds in these old beauty products that have been overlooked by today's cosmetics.

Investigating the dangers of AMB-FUBINACA

Between 2017 and 2019, the synthetic cannabinoid AMB-FUBINACA was Aotearoa New Zealand's deadliest illicit drug.

Across those two years, it is thought to be related to at least 58 deaths, though may have contributed to more than 70.

Cannabinoids are compounds found in the cannabis plant that are able to activate cannabinoid or CB receptors in our bodies. This is because we have our own endocannabinoid system - cannabinoids we make ourselves that bind to these receptors…

Go to this episode on rnz.co.nz for more details

The Nevis Fault is a sleeping giant fault, one that awakens only every 10,000 years or so. This week, a team of geologists use paleoseismic trenching to answer questions about this fault and to figure out the pattern of past earthquakes.

Aotearoa New Zealand is in a collision zone. It is the place where the mighty Australian and Pacific tectonic plates meet. The main fault line runs the length of Te Wai Pounamu and off the east coast of Te Ika a Māui, but the pressure of these two plates meeting causes cracks and fissures across Aotearoa.

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These interconnected fault lines rupture at different times, releasing some of the pressure of this massive collision. Some of them rupture relatively frequently. We know that part of the main fault line, the Alpine Fault, is one of these, producing large earthquakes about every 300 years. Others are low recurrence earthquake fault lines, with a larger time interval of more than ten thousand years between ruptures.

The Nevis Valley fault is one of these low recurrence ones. Found in the grassy high country of Otago it runs the length of the Nevis Valley, up to the Kawerau Gorge. Past studies have indicated that it ruptures every 10 to 12,000 years.

This was determined by a method called paleoseismic trenching - digging a deep trench perpendicular to the fault line and looking at the sedimentary layers for evidence of pre-historic earthquakes. This was first done on this fault in the 1980s, but recent advances in technology and dating techniques warrant a second look, says Professor Mark Stirling of the University of Otago.

Stirling is co-lead of an Earthquake Commission-funded project to investigate the seismic risk in low seismicity areas in Southland and Otago.

Dr. Jack Williams, a postdoctoral researcher at the University of Otago, is also working on this project, and he is part of the team who are carefully cleaning and marking the trench wall. Once the wall is tidied up after the digger's impact, a grid is set up, and the visible sedimentary layers are marked.

https://players.brightcove.net/6093072280001/default_default/index.html?videoId=6307389939112

This is the beginning of the tricky interpretation step…

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It's Prime Minister's Science Prize time! We meet some of the people awarded the 2021 prizes for their mahi.

The annual Prime Minister's Science Prizes recognise the best in New Zealand science research, teaching and communication.

Now the 2021 results are in. Congratulations to all the winners!

Listen to interviews with prizewinners Bianca Woyak, Carol Khor and Professor Dame Jane Harding in this week's episode of Our Changing World.

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Outdoor science for hands-on learning (Bianca Woyak, winner of the Science Teachers Prize)

Bianca Woyak is passionate about what she does - 'People call me high energy. I've got so much energy. I always give 150% into anything that inspires me and I want to do.'

Add a specialist science role, a supportive principal, large school grounds and an enthusiastic school full of students, and you've got a winning combination.

A teacher at Burnside Primary School in Ōtautahi Christchurch, Bianca has been awarded the 2021 Te Puiaki Kaiwhaaho Pūtaiao Science Teachers Prize for her success in engaging students in science through a range of environmentally focused activities.

These have included water testing in the local stream, riparian planting, beekeeping, growing trees for planting in Ōtautahi red zone areas and maintaining the school's veggie patch and fruit trees.

Bianca believes in the power of hands-on approaches and real-world learning that is student-led as much as possible.

This is how the B5 (Burnside Brings Back Boulder Butterfly) project came about. While studying the self-introduced Monarch butterfly the students started to wonder about local endemic species. Working with local experts the team decided to recreate a boulder copper butterfly habitat on school grounds and translocated some of these as yet undescribed butterflies there.

When a new generation hatched, they knew that the project had been a success, and the students are now working with other schools and the local zoo to create boulder copper butterfly habitats there too.

Claire Concannon visits Burnside Primary School to catch up with Bianca and tumuaki (principal) Matt Bateman and learn about some projects from the student scientists themselves.

Improving drug treatment for melanoma (Carol Khor, winner of the Future Scientist Prize)

With our high-UV exposure, Aotearoa leads the world in rates of skin cancer, and melanoma is the deadliest form…

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Researchers from the University of Waikato are tackling the tricky question of how to restore native biodiversity in our urban areas.

For her Masters research at the University of Waikato, Hannah Rogers has gotten to know every green patch, nook and cranny of Kirikiriroa Hamilton.

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Within their Nature in the City Strategy, Hamilton City Council set themselves the ambitious target of moving from 1.8% to 10% native vegetation cover in Kirikiriroa by 2050. Across the city there are hundreds of patches of green that they could target for native regeneration. So where should they start?

What the council really needs is a priority list tool. Something that can point them towards the sites with the most potential for restoration.

And that's exactly what Hannah has been working on.

She has mapped and visited different forest remnants, gullies, parks and patches of bush across the city to assess their potential to contribute towards this 10% goal.

In investigating the potential of the sites, Hannah has used eight different ecological criteria, including what plant species there are and how they are doing, the size of the area available for regeneration, the connection to other green spaces, and the type of landform the site is on.

One of the areas that is particularly interesting, and sits high on Hannah's list, is Hillcrest Park. This is because it contains a small remnant of kahikatea forest at its centre. Some of the trees are estimated to be around 120 years old.

But age isn't everything. The kahikatea remnant is missing the usual array of plants, ferns, epiphytes, and lichens that would be found in a fully functioning, mature native forest.

These are the nuanced aspects of the potential and challenges of restoration at different sites that Hannah's research aims to collect.

Her research feeds into a wider body of work around urban ecological restoration. Led by her supervisor, Professor Bruce Clarkson, the People, Cities and Nature research programme investigates the best ways to bring biodiversity back into cities.

The programme involves multiple universities and institutions and conducts research in several urban areas around Aotearoa. Bruce says that while there are obvious challenges to urban restoration, there are many benefits too, both for nature, and for people.

To learn more

In Urban lizards Alison Ballance speaks to researcher Chris Woolley about his work finding lizards in Wellington as part of the People, Cities and Nature research work. …

Go to this episode on rnz.co.nz for more details

We join Marine Science PhD student Namrata Chand on her Autumn field work collecting seaweed samples to learn more about this 'underdog of the ocean'.

Namrata Chand began diving in the coral reefs and warm crystal-clear waters around her native Fiji. Diving to sample seaweed in Otago Harbour for her PhD is quite a different experience.

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'I describe it as refreshing' she says, 'My first dive in Dunedin was in nine-degree water'.

Namrata, or Nam, is studying a type of endemic (found only in New Zealand) red seaweed called Adamsiella chauvinii. Instead of attaching to rock like kelp, this seaweed species can grow on the soft sediment habitat found in Otago Harbour. It is thought to play important roles for this ecosystem including taking up nutrients from the water and providing habitat for a range of other seaweed species and marine creatures.

For her research, Nam wants to understand where this red seaweed grows in the harbour and in what quantities, which nutrient, light and temperature conditions it likes, and what other seaweed species grow with it.

To do this, she has been sampling seaweed at sites in three different areas of the harbour. The samples are taken back to the University of Otago's Portobello Marine Laboratory where Namrata sorts them into different species and weighs them to get the biomass of each type.

Alongside this, over the last two years, Nam has been gathering data on the light and temperature conditions in each area, as well as water samples to do seasonal nutrient analysis.

In the footsteps of female phycologists, Nancy Adams (after whom the species is named), and her co-supervisor Professor Wendy Nelson, Nam has also begun pressing some of the seaweed samples she has collected. This has helped her to get up close and personal with the different species, aiding her identification skills. But it will also be part of her PhD legacy - Nam will deposit her pressed seaweed collection into the University of Otago herbarium for future students to be able to view and use.

In this episode, Claire Concannon joins Nam on her Autumn seaweed sampling trip to learn more about this 'underdog of the ocean', and the art of seaweed pressing.

To learn more

Scientists elsewhere in Aotearoa are growing macroalgae for research purposes and to explore potential uses of native seaweed and freshwater macroalgae. Listen to this episode about the Facility for Aquaculture Research or Macroalgae in Tauranga Moana…

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Pūtahi Manawa / Healthy Hearts for Aotearoa has an ambitious goal - to close the inequity gaps in heart health. Researchers in this Centre of Research Excellence explain the gaps that exist and how they plan to address them.

Cardiovascular diseases - disorders of the heart and blood vessels - are the leading cause of death globally. In Aotearoa, alongside cancer and respiratory diseases, they are one of the leading causes.

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Cardiovascular diseases are also responsible for a large portion of the difference in life expectancy between Māori and non-Māori and Pacific and non-Pacific people.

Life expectancy is a term used for the average period that a person might expect to live. In Aotearoa there is a difference in life expectancy of about seven years between Māori and non-Māori, and about five years between Pacific and non-Pacific.

A Centre of Research Excellence (CoRE) is aiming to address these, and other, heart health inequities. Pūtahi Manawa / Healthy Hearts for Aotearoa is one of ten CoREs, whose funding began in July 2021, and will run until December 2028.

Pūtahi Manawa have set ambitious goals - the Centre aims to address heart health research and health-care gaps that affect Māori, Pacific peoples, women, and rural communities. To do this, it will need to be 'business not as usual' says co-director Dr. Anna Rolleston. That is, a new way of doing research - working with communities to research what is important to them, and within their world view.

While based in the University of Auckland, as a CoRE, Pūtahi Manawa has partnerships with other Universities and groups. Researchers can apply for funding and support if their plans fit with the Centre's goals and values.

One of the partners in the CoRE is the University of Otago's Christchurch Heart Institute. As part of her work in Christchurch Dr. Allamanda Faatoese is investigating the risk factors for cardiovascular disease among Māori and Pacific people. Allamanda has also been learning from these communities about the barriers to them participating in research.

In the University of Auckland, Dr. Anna Ponnampalam has been investigating the intergenerational heart health impacts that can result from pregnancy complications. Anna has focused on gestational diabetes - when the person develops diabetes during their pregnancy. While gestational diabetes generally resolves after pregnancy, it leaves both the pregnant person and their baby at greater risk for developing diabetes and heart disease later in life…

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Claire Concannon meets with some of the people working to protect New Zealand's naturally rare ecosytems and the endangered plants found within them.

Aotearoa is home to over 70 naturally rare ecosystems - places that make up a tiny amount of the total area of New Zealand but can hold incredible amounts of biodiversity.

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Naturally rare ecosystems happen when there are distinct environmental conditions within a geographically small area; whether it is the underlying rock, the soil chemistry, the climate in the region and/or the local effects of volcanic, geothermal, river, or ocean activities.

Braided riverbeds, coastal turfs, shingle beaches, salt pans, volcanic lahars, tarns and cushion bogs are all examples of naturally rare or naturally uncommon ecosystems in Aotearoa.

These specific landscapes, soil chemistries and conditions have given rise to unique flora and fauna that live in these places. So what you get is a set of rare, endemic (found only in Aotearoa), plants and animals dependent on specific ecosystems and restricted to very small areas.

And many of these are threatened.

In the Waitaki Valley area of North Otago limestone ecosystems are rare and in decline. When it breaks down, the limestone rock produces rich fertile soil good for farming, and the stone itself is quarried for building. So the land has been extensively modified, and the areas suitable for limestone endemic plants has shrunk.

One of the biggest problems for the limestone-soil specific plants is non-native grasses such as Chewings fescue. The grasses smother the plants, blocking out light, sucking up all the moisture and building big impenetrable root mats that stop new plant seedlings from establishing. The low growing natives just can't compete, and so their numbers have been dwindling.

At the back of the Department of Conservation's Oamaru field station DOC ranger Tom Waterhouse has been growing these limestone endemic plants in a nursery. But as science advisor Dr. Clement Lagrue explains, the longer-term issue is where to put them. Intensive monitoring and hand weeding have saved the plants from extinction for now, but to allow them to flourish a habitat 'reset' might be what is required.

University of Otago Botany Masters student Jacinta Steeds is trying to investigate what scale of reset is needed. She is running a field trial on small plots of land to look at what type of weed removal works best…

Go to this episode on rnz.co.nz for more details

A visit to Scott's Terra Nova hut to learn about the care given to the objects by Antarctic Heritage Trust conservators. This is an edit of the Antarctic Heritage Trust's podcast 'Frozen in Time: Scott's Antarctic Legacy'.

Scott's Terra Nova hut at Cape Evans in Antarctica has a history rich in both triumph and tragedy.

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In January 1911 Scott and his party disembarked from the Terra Nova ship at a site Scott named Cape Evans after his second in command. Along with the dogs, ponies, sledges, food and scientific equipment they had onboard, they also had a prefabricated hut which they assembled at the cape.

This was to be the men's home over the winter, where the scientists in the party would begin to learn about this remote continent, and from where Scott and his team would launch their expedition for the South Pole the next Antarctic summer.

The hut and more than 11,000 artefacts left behind by expeditions still remain today. Stepping inside, the hut seems, as Sir David Attenborough described, frozen in time.

But that is only due to the extensive conservation work undertaken by New Zealand's Antarctic Heritage Trust. In 2007 the trust began a seven year journey to conserve the wooden hut and the artefacts left behind.

From the building itself, to each tin of preserved food left behind, to the equipment and chemicals in the science lab and dark room, the conservation work was painstaking in its detail. Every artefact was documented, cared for and, where possible, placed back in the hut.

In the Antarctic's Heritage Trust podcast Frozen in Time: Scott's Antarctic Legacy the trust's Chief Operations Officer, Francesca Eathorne, visits the hut and speaks to the conservation experts about their work.

Listen to this week's episode to hear an edit of this podcast.

You can hear the Antarctic Heritage Trust's full podcast, explore photos of the hut and artefacts and hear additional audio at https://nzaht.org/frozen-in-time/.

To learn more:

Visit the Saving Antarctic Heritage Our Changing World compilation webpage from 2015 which has different audio pieces about the conservation work both at Scott's hut at Cape Evans and Shackleton's hut at Cape Royds.

Go to this episode on rnz.co.nz for more details

Justin Gregory finds out about a study investigating how pre-term babies are fed during their first few weeks, and whether there is a better way.

Busy and happy, Isla Rothwell is a confident toddler with a great giggle. She loves an adventure.

'Oblivious to danger is the current mode,' says mum Olivia. '" What are you doing on the table and how did you even get up there?"'

But 21-month-old Isla isn't your everyday toddler. She was born seven weeks early, giving her family a big shock.

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Isla was healthy and a good weight, so the morning after she was born, her parents were approached by a researcher from the Liggins Institute, part of the University of Auckland's School of Medical and Health Sciences. Isla and her family were being asked to play a part in a unique investigation into the care of pre-term babies, called the DIAMOND Study.

DIAMOND stands for Different Approaches to Moderate & late preterm Nutrition: Determinants of feed tolerance, body composition and development. The study, which began in 2017 with 528 babies across four different hospitals, is believed to be the largest of its kind in the world, and is run by Professor Frank Bloomfield, a neonatologist and the director of the Liggins.

Each year, around 5000 New Zealand babies are born prematurely (before 37 weeks gestation); 85% of them between 32 and 37 weeks. They usually need to stay in a neo-natal intensive care unit, or NICU, until close to their original due date.

"They look like term babies, they behave in many ways like term babies, and we think their outcomes are like term babies', explains Frank.

But that may not be the whole story, he says.

'These babies are at increased risk of a variety of issues that affect their health in later life. Obesity, Type-2 diabetes, cardiovascular disease and also developmental issues.'

Large scale studies over the last 20 years have followed pre-term babies into adulthood and have uncovered these worrying findings. A variety of factors are involved, but one of them may be the care these pre-term babies receive after birth.

The DIAMOND study is investigating how pre-term babies are fed during their first few weeks and whether there is a better way. And all the babies in the study really have to do is to have a good kai…

Go to this episode on rnz.co.nz for more details

Stories about looking our warming world in the eye, and preparing for what is coming next. Collecting data about extreme temperatures in estuaries to help manage shellfish populations. Plus what might managed retreat of marae threatened by sea level rise mean for MÄori communities.

We know that global temperatures are on the rise, and even if we could stop all greenhouse gas emissions tomorrow some impacts would still be locked in. 2021 was New Zealand's warmest year on record. Could it also have been the coldest year of the rest of our lives?

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In the week that the IPCC has checked our homework and found that global efforts to reduce emissions are coming up short, we need to prepare for a future that includes warmer temperatures, sea level rise and increased extreme weather events. This week's episode includes two stories of researchers doing just that.

The extreme life of a cockle

Estuary intertidal regions are interesting environments uniquely impacted by warming of both the air and the sea. During daytime low tides uncovered sediment is heated by the sun. Incoming shallow water flowing over this hot sand or mud gets warmed to bathwater temperatures.

Therefore, combinations of land and ocean heatwaves, coupled with low tides in the middle of the day when the sun is at its hottest, lead to extreme temperature events in these environments. These are exactly what University of Auckland researcher Dr. Rebecca Gladstone-Gallagher wants to capture.

Rebecca is leading a project to deploy a network of temperature sensors, or loggers, in 25 locations across New Zealand's estuaries. Long term temperature loggers will remain out for a year, capturing the general trend over 20-minute intervals. But to get details on these extreme temperature events, Rebecca is also deploying loggers that will take readings every two minutes.

For these deployments she has chosen hot weeks with low tides in the middle of the day. The loggers will be placed just above and within the sediment, in cockle bed areas, so that Rebecca can get an idea of exactly what the animals are experiencing.

Claire Concannon joins Rebecca and her collaborator Professor Conrad Pilditch of the University of Waikato to learn more about the cockles that live in these estuaries, and how Rebecca hopes that this monitoring will help them.

Rebecca's work is funded by a 2020 Marsden fund.

Coastal marae and sea level rise…

Go to this episode on rnz.co.nz for more details

At the Malaghan Institute of Medical Research a team of scientists are working on what they believe will be the future of cancer treatment in New Zealand.

When she imagines the future of cancer treatment, Yasmin Nouri sees a very different landscape. Instead of chemotherapy, a blunt technique aimed at all fast growing cells, she envisions therapies that are personalised to the patient and targeted towards cancer cells.

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Yasmin hopes that she can play a part in the development of this next phase of cancer therapies. In her final year of her PhD at the Malaghan Institute for Medical Research, she is researching a type of cancer treatment called CAR T-cell therapy. In this therapy, the patient's own immune cells, their T-cells, are genetically modified so that they have a new receptor on them - one that recognises cancer.

Normally our T-cells don't recognise cancer cells as an issue because they are our own cells, rather than a virus or bacteria. The added Chimeric Antigen Receptor (CAR) allows the T-cells to do their job, which is to target and kill threats to the body.

In particular, Yasmin is working alongside the Phase I clinical trial currently underway to investigate the safety and efficacy of the CAR T-cell therapy that has been developed at the institute. This trial is specific to patients with a certain type of B-cell lymphoma who have exhausted all other treatment options. Yasmin is running tests in the lab to get into the nitty-gritty of exactly how this therapy works in the body.

She is part of the CAR T-cell therapy research team led by Dr. Rachel Perret. Some CAR T-cell therapies are currently licensed for use in other countries, including the US, the UK and Australia. However, they are expensive, can have serious side effects, and can only be used on particular types of cancers. The aim of the research team is to investigate ways to make CAR T-cell therapy safer, more effective, cheaper and applicable to a wider range of cancers.

Also part of the team is postdoctoral fellow Dr. Patricia Rubio-Reyes. Patricia is focused on research to make CAR T-cell therapy safer, by installing an 'off' switch that will kill off the T-cells if side effects occur. She is also investigating how CAR T-cells could be used to target cancers that cause tumors.

Listen to the episode to hear Rachel, Yasmin and Patricia discuss their research and their hopes for the future of cancer treatment.

To learn more: …

Go to this episode on rnz.co.nz for more details

Two stories on addressing our energy problem - using AI to maximise locally produced renewable energy and reducing the carbon footprint of ammonia production.

The latest release from the IPCC sixth assessment report on impacts, adaptation and vulnerability didn't hold back on dire warnings. The UN secretary general referred to it as a 'code red for humanity'.

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We know that we can't continue to produce energy by burning fossils fuels. We must reduce energy demand and use alternative energy sources.

We don't have all the answers yet, but researchers at Te Herenga Waka - Victoria University of Wellington are working on some solutions for this energy problem.

Keeping the lights on - sustainable energy systems

A reliable electricity supply underpins our modern life. Most of us get the power we need from the national electricity grid, oblivious to the work that the power companies and Transpower do to balance the competing requirements of supply and demand - when power is produced versus when we want to use it.

But there is a growing interest in a range of renewable energy systems, with electricity produced locally by various solar, micro-hydro, wave and biomass systems, and stored locally for later use. Coming up with the best ways of using these micro power grids is what interests Professor Alan Brent.

Alan heads Victoria University of Wellington's Sustainable Energy Centre, and along with postdoctoral researcher Dr. Soheil Mohseni, Alan spends a lot of time thinking about the way electricity generation might look and work in the future.

Using AI to optimise energy systems

Soheil is developing an artificial intelligence system or AI that he hopes will help small communities work out the best energy system to meet their particular requirements. Soheil's work recognises that each small rural community running its own micro power grid is unique, so there is no one size fits all solution. To account for this Soheil uses optimisation algorithms, in which the computer program repeatedly analyses different scenarios until it identifies the best solution…

Go to this episode on rnz.co.nz for more details

A story of a community taking the lead to investigate their own history. Near the small fishing village of Moeraki, whānau members are doing the work of excavating, sorting, and identifying artifacts from an old Māori archaeological site.

Standing over a stainless-steel sink, spray gun in hand, Robyn Maguigan is ready to wash and sieve a pile of jumbled up bones, rocks, shells and charcoal she has dug up. Items that will help tell the story about how her tūpuna lived.

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Robyn and her whānau whakapapa to Moeraki, a fishing village not far north of Dunedin on the east coast of Te Wai Pounamu. As does archaeologist and Curator Māori at Tūhura Otago Museum Dr. Gerard O'Regan.

So when Gerard spotted a dark line and some obsidian in an eroding cliff face at the edge of the urupā at Tikoraki point on the Moeraki peninsula, he knew he was looking at the remains of an early Māori settlement site.

Digging at the edge of the urupā for a tree planting project organised by Te Rūnanga o Moeraki confirmed this. When fish bones and shells started to surface Gerard realised they had found a midden - an early domestic dumping site where the remains of what people were eating and tools they were using are left.

With erosion threatening the area, and a flourishing rabbit population burrowing into the site, it seemed important to recover and catalogue the material from the midden before the story was lost. Especially when preliminary radiocarbon dating of a pāua shell indicated that it could be from 600 years ago.

But instead of calling in others to do it on their behalf, the community decided to take the lead themselves. Te Rūnanga o Moeraki put out a notice, a pānui, and got warm support from the wider Moeraki whānau, including from Robyn's mum, kaumātua Aunty Reita of the Tipa whānau. With help from archaeologists from the University of Otago, the community have done the excavations at the site themselves - pegging out, digging and sieving to collect the material.

In the next phase the whānau travelled to Dunedin to the archaeology department labs at the University of Otago to wash, dry, and sort through the recovered bones, shells, charcoal and bits of tools.

Claire Concannon visits them in the lab to learn more.

This project is supported by MBIE's Curious Minds Otago Participatory Science Platform funding to enable community involvement. It is lead by Te Rūnanga o Moeraki and Moeraki whānau members, and supported by staff and students from the Archaeology programme at the University of Otago and staff from Tūhura Otago Museum.

Go to this episode on rnz.co.nz for more details

This sea week Our Changing World joins Dr. Kim Currie on the Munida transect time-series - a long running investigation of how the chemistry of the oceans off New Zealand is changing.

Six times a year, for the last 23 years, Dr. Kim Currie has made the same boat journey, for the same reason - to collect valuable ocean chemistry data.

As Kim knows, sometimes good science takes time.

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The Munida transect time series, named after the research vessel it started on, has been running since 1998. Back then, we didn't know about ocean acidification - how the ocean's chemistry is changing as it absorbs carbon dioxide from the atmosphere.

When she started the study, Kim was interested in how New Zealand oceans were involved in the movement of carbon between the land, sea and air. So, she picked a 65 km transect line off the coast of Dunedin, one that crosses an interesting area where subantarctic and subtropical water masses meet, and she began to collect data.

Today, Kim follows this same transect line six times a year and gathers data in the same careful, consistent manner. While the boat steams along, Kim collects a myriad of surface ocean chemistry measurements, as well as water samples for later carbon content analysis.

There is a lot of natural variation in something as dynamic as the South Pacific Ocean. Only because of Kim's careful data collection over a long period have they been able to tease out the trend that shows that the pH of the open ocean is indeed dropping, as a result of the oceans absorbing more carbon dioxide.

For Kim collaboration is key. Collaboration with the global science community to ensure that data is collected the same way and therefore comparable. Collaboration across New Zealand to establish a New Zealand Ocean Acidification Observing Network to investigate coastal changes. And collaboration with staff and students at the University of Otago to maximise the use of the research vessel and the time at sea.

This New Zealand Seaweek, listen as Claire Concannon climbs aboard the University of Otago's research vessel the Polaris II to learn more about this globally important study and to find out about the wide range of other research happening along the way.

Thanks to Dr Kim Currie of NIWA, University of Otago students Erik Johnson, Hannah Heynderickx, Jordon Sparrow, Nico Daudt and Oscar Thomas, University of Otago research technician Judith Murdoch, and to Graeme Loh.

To learn more:

- Listen to this Our Changing World episode about ocean acidification from April 2021…

Go to this episode on rnz.co.nz for more details

Creating safe spaces for wildlife to thrive means benefit for the local community too. This week, two stories on that theme.

We know humans benefit when biodiversity flourishes. This week, Claire Concannon brings us two stories about providing sanctuary for fish, and how local communities also gain from these spaces.

Listen to DOC ranger Tim Shaw and Mountains to Sea director Zoe Studd on Our Changing World

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Marine Reserve Sightseeing

Marine reserves are areas in the ocean completely protected from sea surface to seafloor - safe spaces for marine life to flourish. But, compared to a stroll through a protected area of bush or wetland, it's a bit harder to notice wildlife returning.

The Mountains to Sea Wellington group acts as 'Tinder for nature' - connecting people and te taiao. Some of their summer activities include community snorkel days, a free opportunity for local Wellingtonians to get to know the underwater wildlife in their backyards.

After taking part in one of the snorkel events at Island Bay in Wellington, Claire sits down with executive director Zoe Studd to find out more about the work of the group, the community snorkel days, and the changes she has seen after 14 years of the Taputeranga Marine Reserve.

Making Space for Inanga

New Zealand's native migratory freshwater fish are not having a good time.

The inanga's habitat is being destroyed as they also suffer due to poor water quality, dams and culverts block their way, they get eaten by introduced fish, and each year their juveniles are fished as whitebait. Unsurprisingly, their numbers are in decline.

The West Coast sustainable wild whitebait fisheries project aims to help the threatened whitebait species (inanga, kōaro, and the giant, banded and short jaw kōkopu), by providing more and better habitats for them along the South Island's West Coast.

Having received Mahi mō te Taiao/Jobs for Nature funding, the project, led by the West Coast Regional Council, is working with Conservation Volunteers New Zealand and the Department of Conservation to create a whitebait sanctuary on an 18-hectare site at Wadeson Island just outside Hokitika. In addition, fish passage assessment, weeding and fencing will take place on rivers and streams along the coast.

The West Coast sustainable wild whitebait fisheries project team involves representatives from: DOC, University of Canterbury, West Coast Regional Council, Ngāti Waewae, Te Rūnanga o Maakawhio, West Coast Whitebaiters Association, West Coast Conservation Board and commercial whitebaiters.

To learn more: …

Go to this episode on rnz.co.nz for more details

Alison Ballance catches up with two earthquake researchers. Geologist Carolyn Boulton is a "fault finder", interested in how faults slide. And geophysicist Martha Savage eavesdrops on the earth to better understand why earthquakes do what they do.

Dr Carolyn Boulton is a structural geologist at Victoria University of Wellington and she sees things in rocks that most of us would never notice. Including finding beauty in greywacke, which is a common, rather ordinary grey rock that most geologists would regard as somewhat dull.

Carolyn's real passion, however, is earthquakes and the way faults - and greywacke faults in particular - behave.

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Finding faults

A fault is a sliding zone, where two blocks of rock slip past one another during an earthquake. That slipping is often lubricated by fault gouge, a fine-grained clay-like substance that is created by the grinding pressure of the rocks on either side.

Carolyn has become an expert fault hunter, reading the landscape for clues about its past. Last winter she noticed that big floods in the Hutt River had washed away a thick layer of gravels to reveal a new exposure of the Wellington Fault. She has been returning to the site to study it and collect samples of the fault gouge. She will study these small samples in overseas labs under high temperature and pressure, like those experienced within the fault itself, and she hopes the data will shed new light on why faults sometimes slide and sometimes stick.

Eavesdropping on earthquakes

Geophysicists such as Professor Martha Savage, from Victoria University of Wellington, often use seismic noise to visualise what lies beneath the ground. Noise, after all, is just vibrations and seismic noise is the earth vibrating in response to all sorts of things - including earthquakes, as well as wind, people walking and passing traffic.

Geophysicists use seismographs or seismometers to detect this noise and there is a network of these positioned all around the country.

Martha and colleagues have been developing some sophisticated methods that use the background seismic noise collected by this nationwide network of seismic detectors in new ways. These methods can help determine the structure of the earth and they might also be useful in future for developing earthquake detection and early warning systems.

Martha has also been working on an EQC funded project that is installing seismic detectors around Wellington and the Wairarapa next to existing water monitoring stations, to measure how both the ground itself as well as groundwater levels respond during earthquakes.

To learn more:…

Go to this episode on rnz.co.nz for more details

Claire visits a macroalgae research facility in Tauranga to learn how and why the team there are growing large quantities of seaweed and freshwater macroalgae.

At Sulphur Point in Tauranga sits a warehouse-sized greenhouse, designed for just one purpose - to grow macroalgae.

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The Facility for Aquaculture Research of Macroalgae, or FARM, is key to the work of the University of Waikato's macroalgal biotechnologies programme, led by Dr. Marie Magnusson. The multi-million dollar facility allows researchers to figure out how best to grow large quantities of macroalgae, as well as explore the potential uses of different species.

As researcher Dr. Rebecca Lawton explains, native seaweed or freshwater algae is harvested from different areas of the Bay of Plenty and brought to the facility to be cultivated and studied. First, in small batches to work out what species or individual will grow best in their controlled conditions, and then in larger quantities to extract the component that they need.

The macroalgae can be separated into different fractions and analysed at the on-site chemistry lab, under the watchful eye of Dr. Chris Glasson. With the goal of ensuring every part of the harvested macroalgae is used, the team have been working with industry and other partners on a range of applications, including animal and human food, health supplements and materials science.

In a local collaboration with Aqua Curo, the team have developed a system to allow bioremediation of wastewater by freshwater macroalgae at the nearby Te Puke wastewater treatment plant - the algae sucks the excess nutrients out of the wastewater as a last clean-up step before discharge. And, based on previous research work that showed promise in animal models, and in collaboration with partners at Lincoln University, they are also about to begin a clinical trial investigating the potential of sea lettuce pills to help people with metabolic disorders.

Plus the researchers have also been experimenting with their own seaweed recipes, though some remain.... contentious.

The Enterpreneurial Universities Macroalgal Biotechnology Enterprises Programme and facilities is funded by the Tertiary Education Commission and the University of Waikato. The clinical study mentioned by Dr. Chris Glasson is also partially funded by an internal grant from Lincoln University awarded to Dr Catherine Elliot. The freswhater bioremediation work mentioned at Te Puke wastewater treatment plant is funded by Aqua Curo.

To learn more

Visit the groups webpage

Find out more about the bioremediation project mentioned at Aqua Curo's website.

Go to this episode on rnz.co.nz for more details

Claire learns about honey fingerprinting while Katy Gosset meets a scientist studying the anti-microbial properties of some native plants.

Honey is big business in Aotearoa. An estimated 27,000 tonnes of honey was produced in the 2019/20 season, with the value of honey exports for that time at $425 million. So New Zealand honey is in global demand, but how can you be sure that honey labelled as New Zealand origin was really made here?

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The fingerprint of honey

This is what Dr. Megan Grainger hopes to help address with her latest research. Megan has been investigating the elemental fingerprint of different New Zealand honeys and comparing them across regions and with honey from overseas.

The elemental composition of rocks and soils in different locations is taken up by the plants, represented in the nectar, and subsequently in the honey made from that nectar. By using analytical chemistry techniques and equipment, Megan can profile what elements are in the honey and what concentrations they are found in. By analysing over 200 different samples of honey she has been able to build up a picture of what the elemental fingerprint of honey from different regions in the North Island looks like.

Megan has also identified tiny amounts of so-called 'heavy metal' elements in the honey, things like lead, mercury and cadmium, which are linked to human activity. This has sparked her next avenue of research - figuring out if and how these impact the bee's activities and if they could play a role in declining bee populations and colony health.

Plant powers

When microorganisms get in to the soil from manure spreading or livestock excrement, it can lead to further issues downstream when they get into our water ways and impact water quality.

To figure out how to combat this a team at the Bioprotection Aotearoa research centre have turned to native plants.

After testing 12 native plant species for antimicrobial properties, the team have shown that extracts of some of the species are effective at reducing e.coli contamination in soil in a greenhouse experiment. Extracts from northern rātā and swamp mānuka could reduce e.coli by 90% after 14 days, compared with the 45 days it took to see this level of reduction with a control plant extract.

Katy Gosset finds out more at the Bioprotection Aotearoa Research Centre.

Learn more

Read the Marsden Fund Fast-Start grant summary into Megan's upcoming research.

Megan has her own website where she talks about her research…

Go to this episode on rnz.co.nz for more details

Claire Concannon joins a meteorite hunt on the South Island's West Coast and learns what these rocks from space can tell us about the early formation of our solar system.

In January 1976 Ted Dowie was looking for gold in a river in the mining district of Dunganville near Greymouth when he came across a black, smooth-topped boulder in a dry creek bed. It rang like a bell when he hit it and was unusually heavy. Intrigued, Dowie rolled the boulder up on the stream bank and sent a small sample he had chipped off to New Zealand Geological Survey.

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Mr. Dowie had found a 50.2kg iron meteorite, the name we give to rock or other solid debris that has come from outer space and landed on Earth. The Dunganville meteorite is still the largest of the nine recorded in New Zealand to date, and it is the iron core of a protoplanet from four and a half billion years ago when our solar system was forming.

At that time most of the gas and dust left over from an explosion of a massive star came together to form our sun. Some of the remaining material became protoplanets, with some getting big and hot enough to melt so that they separated out into a dense iron core and a lighter mantle.

A few of these protoplanets went on to become our familiar family of planets, but others got smashed apart before they made it that far. The remnants of these drifted in space, but the odd collision knocked them on a course to land on earth.

A short time after Mr. Dowie's find a further search of the creek bed turned up 68 pieces of the weathered crust. But what if some was overlooked, or if the boulder was just one in a shower of meteorites? Could there be more out there?

These are the questions on the minds of Associate Professor James Scott and students from the Geology department at the University of Otago. Following in Dowie's footsteps, with metal detectors in hand, the team set out to see if they can find a piece of a core of a four and a half billion year old protoplanet in a river on the South Island's West Coast.

To learn more:

Read the 1984 paper that describes the Dunganville meteor here.

Find out more about the recorded New Zealand meteorite falls and finds on the Te Ara website.

Thanks to GNS Science, Te Pū Ao, for providing fragments of the Dunganville meteorite for XRF testing.

Go to this episode on rnz.co.nz for more details

The story of titipounamu, New Zealand's smallest bird, on Otago Peninsula, told by Karthic SS, a wildlife film maker and podcast producer based in Dunedin.

From the bustling hot city of Coimbatore in southern India to the rather less bustling, and definitely cooler, south of Te Wai Pounamu in Aotearoa, Karthic SS* has spent most of his life paying close attention to the sounds around him.

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Now based in Ōtepoti, Karthic produces the Tune into Nature podcast, telling stories of New Zealand wildlife and conservation, and encouraging his audience to listen to the sounds of the natural world around them.

In India, that included the odd interaction with elephants. But in Aotearoa it often means birds. Lots of birds.

This week, we play an episode of the Tune into Nature podcast about titipounamu (rifleman) on the Otago Peninsula.

Weighing just 6 grams, the titipounamu is New Zealand's smallest bird.

The Otago Peninsula Biodiversity Group have been taking care of the pairs that live on the Peninsula, including setting up nest boxes for them.

Though one pair famously declined these in favour of nesting in a possum trap!

Join Karthic, Shanta McPherson and Marcia Dale on a forest walk to learn more about titipounamu.

The Tune into Nature podcast is created by Karthic SS. It is supported by Otago Access Radio and the Centre for Science Communication, with funding support from the Otago Regional Council's Ecofund. You can find it on Facebook, Instagram, and on your regular podcast provider. The podcast Karthic created as part of his studies, mentioned in this episode, can be found here.

*Where Karthic comes from it is usual not to use family names - instead the first name followed by the initials of father's or mother's name is used.

Go to this episode on rnz.co.nz for more details

Summer science continues with a play of a science related episode from RNZ's Voices podcast. In 'To spray or not to spray' we meet Tim Vandervoet as he investigates ways to reduce insecticide use in orchards.

This week on Our Changing World, as part of the Summer Science series, a science related episode from the Voices podcast.

To spray or not to spray - from cotton fields to codling moth

As a Peace Corp volunteer in Malawi, Tim Vandervoet developed a passion for using agriculture and science as a tool for social change - reducing insecticide use through more biological control of pests being one way.

Vandervoet was raised in Arizona where the family business involved the import of agricultural produce from Mexico into the US.

Although slightly removed from his direct area of interest, it was still an important influence from the periphery that steered him to agricultural science and entomology.

The expansive cottonfields of the Southwest in Arizona were where he began as a scientist, working on maximising biological control of whitefly.

After landing a job at Hawkes Bay's Plant and Food Research Vandervoet focus has now shifted to helping develop more effective biocontrol of the codling moth here.

Each year New Zealand exports apple worth nearly 800 million dollars to European and Asian market - both markets with stringent residue regulations and pest-free standards.

Achieving both these in order to maintain access to these crucial markets means a need for to explore newer and more effective ideas - ideas that help ensure high quality fruit with that ultra-low pesticide residues and pest-free status.

A tactic that has been refined in Hawkes Bay is the air-dropping of sterile codling moths imported from Canada.

These are drone-dropped by the thousands over demarcated orchards and disrupt mating behaviour of the moths and suppress the population.

Covid-19 has disrupted this tactic - with no flights coming in, the import of these moths from Canada has been brought to a standstill for the moment.

So it's back to simple methods. Aside from phermone-laden traps for codling moth, Vandervoet uses simple cardboard traps for the larvae strapped around the tree-trunks, offering several more data points for studying the pest population in orchards and developing more effective biocontrol strategies around this.

"Lowering toxicity, reducing the use of insecticide is obviously good for growers, the environment land and consumers" says Vandervoet

"I'd take an NZ apple over a US apple any day" Tim laughs - "New Zealand has a very good reputation for very low residue fruit"…

Go to this episode on rnz.co.nz for more details

Centre for Science Communication student Laura McDonald speaks to Dr. Mike Palin about lead contamination in the environment.

Laura McDonald learns the backstory to the discovery of lead contamination in the environment.

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After the incident in Waikouaiti in Otago where toxic lead was found in the towns drinking water, there has been much question as to where the lead is coming from. After talking to geochemist Mike Palin, his findings suggest that the lead is very low in the natural waters indicating that the lead is likely coming from the towns water pipes, which are in the process of being removed and replaced. Lead is toxic, so why is it that it's in the water pipes beneath our towns that deliver our drinking water?

This links to an interesting controversy that started in the 1950's with a geochemist named Clair Patterson. For his PhD, Clair Patterson was tasked with figuring out the age of the earth using lead isotopes in meteorites. However, he came across some difficulties due to the high concentrations of lead in the environment making it impossible to decontaminate and measure the lead in his meteorite samples. After building a clean laboratory Patterson figured out the age of the earth, and his next mission was to address the issue of the lead contamination in the environment.

During this time lead was being used as an additive to petrol as it improved motor performance and was also being used in water pipes, taps, paint and even children's toys. Clair Patterson advocated to the US government to get lead removed from these sources as he claimed that it was contaminating the natural environment. To this, the petroleum companies argued that lead is natural in the environment and that the lead from petrol is hardly contributing to the lead already present in the atmosphere. They also brought a medical doctor on board, Robert Kehoe, who claimed that there was no evidence that lead was toxic to humans. For Clair Patterson to prove that lead was contaminating the environment he collected a range of evidence which included ice cores from Greenland and samples of deep ocean water which proved that lead had only been occurring in such high concentrations since it was added to petrol in the 1920's. After years of work Clair Patterson finally won his battle when the US passed the Clean Air Act in 1970 and when lead was subsequently banned from paint in 1977 and from petrol in 1986.

…

Go to this episode on rnz.co.nz for more details

Summer science continues with a play of a science related episode from RNZ's Black Sheep podcast. Invasive tells the story of one man who released thousands of invasive fish into New Zealand's rivers, lakes and streams. Programme Code

This week on Our Changing World, as part of the Summer Science series, we bring you one of our favourite conservation related episodes from the Black Sheep podcast.

Invasive: the story of Stewart Smith

Between the 1960s and late 2000s Stewart Smith went on a one-man crusade, releasing thousands of invasive fish into New Zealand's rivers, lakes and streams.

One kind of fish he introduced is now so widespread it's been declared an "acclimatised species", meaning the authorities have basically acknowledged it is impossible to remove it from the wild.

"The amount of damage he did was incalculable," says science journalist Charlie Mitchell, who wrote a feature on Smith for Stuff.co.nz.

"He could be positioned alongside the people who released stoats and weasels and ferrets in New Zealand," says Bryan Winters, who wrote an authorised biography of Smith entitled That Pommie Bastard.

So who was Stewart Smith?

He was a devout communist with a stubborn streak a mile wide, a conspiracy theorist who spent years locked up in a conscientious objectors camp, and an environmental imperialist dedicated to the cause of "improving" recreational fishing in New Zealand.

Subscribe free to Black Sheep: Apple Podcasts, RadioPublic, Spotify, RadioPublic or Stitcher.

Go to this episode on rnz.co.nz for more details

Centre for Science Communication student William Bowden speaks to Dr. Mike Joy & Dr. Tim Chambers about the issue of nitrates in New Zealand's waterways.

William Bowden dives into the controversial topic of nitrates in our waterways.

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Dr Mike Joy is a freshwater ecologist at Victoria University of Wellington. As a scientist he works in the field, studying freshwater organisms and the complex relationships they have with the aquatic environment. As a science communicator however, Mike has become an active participant in one of New Zealand most controversial issues; the nitrate pollution of New Zealand's freshwater.

On this podcast, Mike discusses the issue in depth, tracing the path of nitrogen from the fertiliser factory, through the industrialised farm and into the river network, highlighting the increasingly detrimental impacts it has on ecosystem health as it accumulates there. However, it is on the subject of setting nitrate limits and enforcement where this issue truly becomes controversial.

As a member of the Science and Technology Advisory Group, set up by the Ministry for the Environment, he and other scientists have recommended nitrate limits for our rivers and drinking water supplies. However, if the nitrate limits recommended by this group of scientists were to be adopted and enforced, it could spell the end for industrial dairy farming in some of New Zealand's largest dairy producing regions. As a result, an unavoidable conflict between protecting the environment and protecting the economy emerges.

What may prove to be non-negotiable however, is human health. The link between nitrate and colorectal cancer is an existing debate within the nitrate issue. However an even newer discovery; the emerging causal relationship between nitrate consumption and birth defects in new born babies, could have the potential to tip the balance of public opinion once and for all. So to discuss these emerging health issues, I interviewed Dr Tim Chambers, a leading public health researcher from the University of Otago.

If you are interested in the freshwater environment, the future direction of New Zealand's economy, and emerging public health issues, then be sure to tune in and listen to the podcast.

Go to this episode on rnz.co.nz for more details

How to deal with unwelcome visitors. Katy Gosset learns about a native fungus that might help in the battle against wilding pines. And two national research programmes combine on an expedition to protect our oceans from plastics and invasive species.

Invasive species in Aotearoa are the unwelcome guests who have taken over, made a mess, and just won't leave. Plants that smother ecosystems, seaweeds that take over ocean floor habitats, insects, fungi and bacteria that harm native species. Not only that, but others are constantly knocking on the door. This week, stories on keeping them out, and keeping them in check.

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Pine-fighting fungus

New research has shown a native fungus could help slow the spread of invasive wilding pines.

Conservationists estimate that these weeds now cover 1.8 million hectares of land across New Zealand and the Ministry of Primary Industries forecasts that as much as 20 percent of New Zealand could be covered by unwanted conifers in as little as 20 years. The cost? Around $100 million annually in lost productivity, irrigation, hydro-electric power and fire control. And if the wilding pines continue to spread the cost to our economy could reach into the billions.

Katy Gosset meets a Canterbury Masters student who hopes to halt the pines' progress by innoculating the felled trees with armillaria fungus.

Keeping an eye on the oceans

Unwelcome visitors from the ocean include both invasive species and plastic pollution; keeping both at bay is a massive job.

Two national collaborative research programmes are trying to tackle these issues - the AIM2 (Aotearoa Impacts and Mitigation of Microplastics) project and the Marine Biosecurity Toolbox programme. Both involve large teams of scientists from multiple organisations.

In 2021 these research programmes came together on two expeditions coordinated by the Blue Cradle Foundation to gather biosecurity and microplastics data, first in the Hauraki Gulf and then in Fiordland.

Collaboration and data sharing between the two teams is key, as plastic rafts could act as vehicles for invasive species to arrive in the waters around Aotearoa. Scientists across the two projects are working to identify what different organisms tend to interact with different kinds of plastic so that they can make predictions about what threats the marine environment might face.

Listen to how the researchers sample for plastics, and use environmental DNA methods to survey for biosecurity threats in the Hauraki Gulf…

Go to this episode on rnz.co.nz for more details

Chemical isotope analysis is a powerful technique - Dr. Charlotte King explains to Claire how she uses it to reconstruct past lives of forgotten people from the Otago gold rush.

Our skeleton, our nails, our tissues, are all made from basic chemical elements. These elements pass from the soil, to growing plants, to the food we eat and into our bodies. By following this pathway backwards, one researcher is learning about the lives of some forgotten people of the Otago gold rush.

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In a small lab in the Department of Anatomy at the University of Otago, research fellow Dr. Charlotte King is carefully photographing a piece of bone, teeth and some hair. She is documenting them before she takes a small section to do her research - chemical isotope analysis.

Charlotte is part of the Southern Cemeteries Archaeology project - a group of researchers working with local communities who were concerned about unmarked graves related to the gold fields of central Otago.

The project has run over several years and has involved excavations of unmarked graves at several cemetery sites in Milton, Lawrence and Drybread. Once human remains are recovered, many lines of evidence are used by the team to reconstruct where these people came from and how they lived.

The aim is to learn about them, and their lives in the Otago gold fields, before they are reburied in marked sites.

Charlotte is investigating the ratios of isotopes of different chemical elements in the human tissues recovered. Because different chemical isotope signatures are present in different rocks, soils and food, Charlotte can use this to uncover clues as to where the people were from and what kinds of food they ate at different times during their lives.

Learn more:

A previous Our Changing World episode was recorded at the archaeological dig in Milton.

The Drybread cemetery dig was reported on with several interviews at the time:

On Nights, before the excavation

Morning report

Checkpoint

The project's website contains further information about their findings

The Southern Cemeteries Archaeology project is co-lead by Prof. Hallie Buckley and Dr. Peter Petchey. The excavations at Drybread cemetery were done in consultation with, and permissions from, the Drybread Cemetery Trust and Leslie and Maisie Wong of the Otago-Southland Chinese association.

Go to this episode on rnz.co.nz for more details

Sci Fi / Sci Fact is a new podcast series in which scientists from New Zealand's MacDiarmid Institute talk to RNZ host Bryan Crump about whether some of science-fiction's most popular concepts could actually come true.

Sci Fi / Sci Fact is a new podcast series in which scientists from New Zealand's MacDiarmid Institute talk to RNZ host Bryan Crump about whether some of science-fiction's most popular concepts could actually come true.

Follow Sci Fi / Sci Fact on Apple Podcasts, Spotify, iHeart Radio, Google Podcasts, Stitcher or wherever you listen to podcasts.

Taken from the popular Materials: Fact or Fiction segment which runs on Nights with Bryan Crump, this podcast series delves into the mines of Moria in Middle Earth to find out what Frodo's mithril vest might be made from.

It travels into deep space with the crew of the Starship Enterprise to find out if dilithium crystals are real and if they really could separate matter and anti-matter.

And don't miss the episode looking at what aspects of quantum physics could explain just how Santa manages to deliver all those presents on Christmas Eve.

Go to this episode on rnz.co.nz for more details

Two stories on keeping an eye on river flow - helping fish to migrate back upstream, and development of a national river flow forecasting tool.

Fish friendly flow

For thousands of years several species of New Zealand's native freshwater fish have been making journeys from the rivers, down streams, to the ocean, and back upstream again, as part of their natural lifecycle. Until we started putting things in the way.

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Look out into the fields and ditches of New Zealand, along the roadside and down on the farms, and you'll see them - culverts. Structures designed to channel water past an obstacle or under structures, such as roads. Often made of steel, plastic or concrete in either a box or pipe design, many in Aotearoa have been designed with water flow considerations in mind, but not the needs of migratory fish.

Changing the bottom of a stream into a uniform flat piece of concrete can mean very fast and uniform water flow. But native juvenile fish, on their return from their ocean phase of their lifecycle, just can't swim upstream against these flows. They're too fast. Plus, many culverts have steep drop-offs that some fish can't climb up and over.

Different solutions to this problem have been proposed - including remediation of the existing culverts - that is, installing devices to make them more fish friendly. Because if these fish can't make it back upstream, we lose the next generation, and most of these migratory species are already classified by the Department of Conservation as threatened with extinction or at risk of becoming so.

Claire Concannon catches up with Stephanie Patchett, an engineering master's student from the University of Canterbury, as she begins her research testing some of these devices in real world settings. In collaboration with a team of scientists from the Department of Conservation, the study will look at fish numbers up and downstream of each culvert before and after the devices have been installed to figure out which devices work best in different situations.

Forecasting the flow

It rains a lot here in New Zealand. A lot.

Between 600-1600mm falls here every year. For context, Australia gets around 400mm annually, although a more apt comparison might be with the United Kingdom, which records around 900mm every year.

Westerly winds scream in from the roaring forties, hit our high mountain chain and then rain falls, in vast quantities, sometimes very quickly…

Go to this episode on rnz.co.nz for more details

A team of scientists are installing an array of seismic sensors along the South Island's Alpine Fault. Claire Concannon joins them to find out how and why.

Standing in the last back field of a deer farm near Whataroa on the South Island's West Coast, orange high-vis vest on, shovel in hand, Professor John Townend is looking for the perfect spot - not too wet, not too stony, with a good view of the sun. A good space to dig a hole and bury something that may help us learn what is to come in the next big earthquake.

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This is to be the site of one of the South Island Long Skinny Array (SALSA) seismic sensors - a string of 55 sensors spaced 10km apart along 450km of the Alpine Fault between Maruia and Milford Sound.

The Alpine Fault is the on-land boundary between the Pacific and Australian plates, running almost the length of the South Island. Paleoseismology research has shown that the fault has a remarkably regular history of producing large earthquakes; one about every 300 years. The last large earthquake was in 1717 - 304 years ago, making it likely that the next severe earthquake on the Alpine Fault will occur within our lifetimes.

The aim of SALSA is to increase our understanding of what will happen as a result of that earthquake. The seismic sensors John and his team are using are able to detect a wide range of frequencies of seismic waves, including the background hum, or ambient seismic noise, that is produced when ocean waves hit the land.

Previously, scientists would have deleted this 'noise' from their data, or avoided capturing it in the first place. However, recent advances have shown that collecting this type of data over a long period and running analysis on it can give insight into how seismic waves will move along the fault and affect ground shaking further afield. It allows scientists to create 'virtual' earthquakes - they can model how the energy will transfer without having to wait for an actual earthquake to occur.

First though the sensors have to be installed, a mammoth task in itself as the team must contend with the challenges that the Southern Alps present - different terrain, difficult access and changeable weather. The full team of 11 people are working together over two and a half weeks to fit as many sensors as possible. Claire Concannon joins a group as they install one sensor to learn all about how and why they are doing it.

Listen to more episodes about earthquakes and earthquake science by visiting our collection.

https://www.youtube.com/watch?v=bU_O6Qe6Knk…

Go to this episode on rnz.co.nz for more details

Katy Gosset speaks to a PhD student designing new tech to catch predators and Claire Concannon meets the team who are working to restore a unique landscape on the South Island's West Coast.

Whistles, song, calls, booms, rustling in the undergrowth, hooting at night. How busy the bush of Aotearoa must have been, this land of birds, before human-introduced predators and tree clearance. Today, two stories of people committed to the restoration of our forests, taking steps towards returning some of this former glory.

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New lure technology

The battle to save our native birds is heating up with Predator Free 2050 spending $2.4m to enlist fresh scientific talent to the cause.

Department of Conservation figures show 4000 native species are currently under threat, with about a quarter of them in serious danger of extinction.

Predator Free 2050 has now funded six young scientists to come up with new solutions to the problem.

Katy Gosset meets one University of Canterbury student whose intelligent lure system will make it easier to trap predators. Ben McEwen hopes his work will play a role in returning native bird song to the bush.

Planting the polje

Dramatic forest-clad limestone cliffs surround a flat expanse with snakes of gravel - a clue that sometimes water flows through there - the Bullock Creek area just north of Punakaiki is unique in Aotearoa.

This wetland valley of flat ground with steep walls is known as a polje, having formed when a giant cave of series of caverns collapsed. The soft, dissolvable limestone results in unusual hydrology - at times the Bullock flows underground, before resurfacing, and the area is subject to flash flooding. This makes it far from ideal for the farming purpose it was once cleared for.

Conservation Volunteers New Zealand began replanting some of this area in 2020 using Te Uru Rākau, One Billion Trees programme support and are continuing with funding from Jobs for Nature, Mahi mō te Taiao.

Claire Concannon visits the team on the West Coast to learn about this special landscape and find out how the restoration work is going.

Go to this episode on rnz.co.nz for more details

On the 100th anniversary of radio in Aotearoa, Claire Concannon learns about the very first broadcast, explores how radio works, and finds out about current research into communicating using light.

How are you reading this? On a computer, laptop, mobile phone? Connected to the internet by a cable or wirelessly through the use of radiowaves? Instantaneous round-the-world communication is now an everyday - almost essential - part of life. And this week, radio celebrates a major milestone.

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A century ago, on the 17th November 1921, Professor Robert Jack of the Physics department in the University of Otago completed New Zealand's first successful radio broadcast using equipment he had assembled in his lab. It was the beginning of radio stations in Aotearoa New Zealand.

That equipment sits in Tōitu Otago Settlers Museum in Dunedin today, to help tell the story of that broadcast. But Professor Jack was tapping in to technology that had already been explored by others across the world, and which can be traced back to the mid-1880s when physicist Heinrich Hertz was the first to deliberately produce radio waves.

Hertz was experimenting to prove the existence of electromagnetic waves - synchronised oscillations of electric and magnetic fields, waves of energy that can move through space. These electromagnetic waves exist on a spectrum from waves with a very long wavelengths (time between peaks) and low frequencies (number of wave oscillations per second) to those with very short wavelengths and high frequencies.

By understanding the different properties and behaviours of waves along this spectrum, from radiowaves to microwaves, infrared, visible and UV light, X-rays and gamma rays, we have been able to harness their power.

Listen to the episode to hear Tōitu Otago Settlers Museum curator Pete Read talks about the background to that first broadcast by Professor Robert Jack. Then Associate Professor Harald Schwefel of the University of Otago explains how radio works and talks about his latest cutting edge research into improving communication via light.

Thanks to Ngā Taonga Sound and Vision for their help with archival audio. This episode also contains two sound files from NASA: Chorus Radio Waves within Earth's Atmosphere and Kepler: Star KIC7671081B Light Curve Waves to Sound.

Go to this episode on rnz.co.nz for more details

Claire visits the team at K9 Medical Detection Charitable Trust to learn how their dogs are being trained to detect bowel and prostate cancer.

Levi loves what he does. He gets picked up each morning at 8:30am, happy and excited to go to work. He spends his time investigating samples, figuring out whether they contain cancer or not. His payment - toys and play time.

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Levi is a German Shephard with a finely tuned olfactory system - a nose perfectly adapted to smelling, around 225 million scent receptors and a large part of the brain designated to distinguishing smells.

He is part of the K9 Medical Detection Charitable Trust team based at AgResearch in Invermay. Alongside his colleagues Wētā, Frieda, Magic and puppy Ace, Levi has been training to do one job extremely well - sniff out bowel cancer.

Trainer Courtney Moore works with the dogs - helping them to 'imprint' on the cancer scent from an early stage. It is unclear exactly what the dogs are sniffing out - it is likely to be metabolites or volatile organic compounds released by the cancer cells into the solutions they are in - but the dogs are able to distinguish a unique cancer 'scent'. The imprinting is part of the first 'proof of concept' phase, a validation step that the dogs must pass through where they show they can selectively pick which of the saline samples contain the cancer cells, and ignore those that contain healthy cells.

Levi has already passed this validation step with flying colours with regards detecting bowel cancer, and the team hope that Wētā will soon follow. Frieda has recently passed for prostate cancer detection with 100% selectively and specificity. The next phase is a test of diagnostic accuracy, says director Pauline Blomfield. This would involve the dogs investigating urine samples from patients.

The goal is to provide a non-invasive, value-added tool to existing cancer screening methods. In addition, identifying the volatile organic compounds the dogs are detecting could provide a further opportunity to develop specific and selective diagnostic tests based on these molecules, says Professor Sarah Young of the University of Sydney, one of the scientists who work with K9 Medical Detection.

While it is still relatively early days in terms of the dogs providing help with cancer diagnoses, the dogs have achieved good results so far and the team have faith in their strong work ethic and amazing noses. Levi is just happy to do something he loves each day.

Learn more: …

Go to this episode on rnz.co.nz for more details

Claire Concannon hits the Central Otago hills with Botany PhD student Ben Teele to imagine the landscape as it use to be, and to follow the clues to find leftover pockets of tōtara trees.

The hillsides of Central Otago are known for their golden grass and tussock slopes with scattered low-lying shrubs. But once this landscape was covered in tōtara forest. Now only a few trees remain, cryptic and scattered across the large region, and Ben Teele is on the hunt for as many of them as he can find.

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University of Otago Botany PhD student Ben Teele is mapping and 'health-checking' the remaining tōtara tree populations. Some large, some small, some regenerating well, but others struggling.

Clues are key to him finding the trees in this vast landscape, and he finds them in all kinds of nooks and crannies - tōtara sightings from geologists, botanists or hill walkers, environmental reports to local authorities and even historical gold mining records describing where tōtara grew.

Ben is looking for the thin-barked tōtara species well adapted to this semi-arid environment. Once widespread, they are now restricted to rocky bluffs high on the hills, which helped them survive the fires that swept across the region after human arrival.

Ben wants to collect the seeds and grow some cuttings from these Central Otago survivors to ensure good genetic diversity, and to figure out what the optimal conditions might be to help them regenerate, and spread back down the hills to the lowers slopes they once inhabited. His research is funded by the Ministry for Primary Industries One Billion Trees programme, with the aim of planning one billion trees across Aotearoa by 2028. Ben hopes that at least some of those trees planted will be thin-barked tōtara in Central Otago and imagines a future where this landscape could look very different.

Go to this episode on rnz.co.nz for more details

Claire Concannon hears how the the New Zealand Plant Conservation Network's favourite plant competition is shaping up, while Katy Gosset learns about research to improve the quality and growth efficiency of grapevines.

If you had to choose, what would your favourite plant be? Something beautiful and flashy like kōwhai or pōhutukawa? Or maybe something subtle like a native moss or grass? Or perhaps you would go with something that produces delicious fruit like a cherry or peach tree? This week, we pick favourites.

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The dwarf plant with long odds

From a childhood exploring shrub-filled gorges around Taranaki, through a career learning about and looking after threatened native plants with DOC, John Barkla has never lost his love of plants. Currently John is the president of the New Zealand Plant Conservation Network - an organisation dedicated to advocating for plant conservation and sharing information about Aotearoa's native flora.

On a stroll through Dunedin's town belt John speaks to Claire about the threat status of native plants and the issues they are facing, as well as introducing her to some of the locals. Plus he puts his vote behind a dark horse, outside contender for the Favourite Plant competition - korthalsella lindsayi - the dwarf mistletoe.

Perfecting the pinot

A plant native to Burgundy in France, the Pinot Noir grape has found a home in New Zealand, and is a favourite tipple for many both here and abroad.

But keeping the quality consistent while ensuring yield for the years to come is a balancing act for wine makers.

Katy Gosset meets Minoo Mohajer, a PhD student at Lincoln University, who has found a way to help, using focused grapevine management to control yield while ensuring the favourite drop still tastes just as good.

Listen to more

- Learn more about the life of mistletoe and its vine cousins in Epiphytes - high-rise plants

- It's not just plants that are important in brewing wine - in the episode Using local yeasts to make distinctive NZ beers & wine Peter Griffin learns how New Zealand scientists are looking for native yeasts to give local brews a unique flavour.

Go to this episode on rnz.co.nz for more details

This week on Our Changing World, Aotearoa Science Agency's Damian Christie speaks to three scientists about the world of data.

As we approach the end of our second year dealing with Covid-19, it's notable how many of us are now familiar with the basic concepts of epidemiology. Social conversations are no longer about house prices and sports results, but debates over elimination versus suppression, the stringency of our lockdown measures, and the current R-value as our daily cases creep higher.

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We have become armchair experts in looking at data, searching for meaning - and hope - among the numbers. What does the latest study say about the best gap between vaccines? What do ICU admissions tell us about our level of protection? What proof do we have against the deniers?

For scientists, making sense of the data is all part of the job. Damian Christie speaks to two scientists who work with respectively some of the the largest and smallest data sets there are - from the mindblowing amount of information collected every single hour that helps researchers make sense of our changing climate, to a marine scientist tasked with tracking the mere dozens of māui dolphins remaining in Aotearoa. They discuss how their own research journeys, and how they have watched as the public interest in using data for decision making has grown during the pandemic.

https://youtu.be/I6MTGfOjCu8

Thanks to Professor James Renwick, Dr Andrew Chen and Associate Professor Rochelle Constantine for their contributions to this episode.

You can read more about Associate Professor Rochelle Constantine and the MAUI63 drone project here: https://www.maui63.org/

Go to this episode on rnz.co.nz for more details

Claire Concannon hears from Dr. Brigid Ryan of the University of Auckland about the New Zealand genetic frontotemporal dementia study and speaks to some of the family members involved in this unique research study.

Frontotemporal dementia is one of the sneakiest forms of dementia, arriving with no warning signs and slowly chipping away at a person's personality, behaviour and language. It even impacts your thought process and judgement. If the disease is triggered by an unknown cause, people may not get properly diagnosed until quite late. However one unique New Zealand study into frontotemporal dementia is trying to change all this.

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What happens in brain cells to cause dementia actually occurs over a long time period. The goal of the New Zealand genetic frontotemporal dementia study, being led by Dr Brigid Ryan in the Centre for Brain Research in the University of Auckland, is to identify signals that the body is giving off in the early stages, before symptoms occur, that can be used as indicators that the person is going to develop dementia.

Known as preclinical biomarkers, the researchers won't know exactly what they are until they find them, thus, they need to run many test on participants each year - blood tests to look for microRNA changes, smell tests to check for olfactory deficits, MRI's and memory tests to look for changes in the brain structure and function.

This is where the commitment of the participants come in. This research is only possible because one New Zealand family, following the diagnosis of one of their family members with a version of frontotemporal dementia caused by a genetic mutation, have put themselves forward to be part of the study.

Claire Concannon learns from the researchers about this type of dementia, the details of the study and what they hope to find, while two of the family members involved share their thoughts and experience.

Learn more:

- You can read about the study in a piece published in the New Zealand medical journal

-Learn more about the Centre for Brain Research in this story by Dr. Victor Dieriks on his work on Parkinson's Disease…

Go to this episode on rnz.co.nz for more details

Stories about the potential of bioengineering to transform health care. A new tracheostomy kit design that has halved the time for emergency operations and 3D bioprinting of tissues to help healing.

Stem cell infused wound dressings that promote healing, bone scaffolds that help knit breaks before dissolving naturally and clever device design to half the time of emergency life-saving procedures are all ways bioengineering is changing healthcare.

Bioengineering is paving the way for new and better healthcare, and new research projects - with 3D bioprinters at the University of Otago and tracheostomy kit design at the University of Canterbury - are looking for new ways to save lives.

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Ordering up organs

The over-arching goal for 3D bioprinting bioengineers, such as Dr. Jaydee Cabral and her team at Otago's Chemistry Department, is to develop 3D printed organs made of the patient's own cells for transplant. But it will be a while before they get there.

Cabral is focusing on overcoming one of the major roadblocks on the path to those new 3D printed organs - getting the vascularisation right. That means figuring out how to make the blood vessels needed to spread nutrients through the organs and take away waste material, and they are tricky to recreate. So Cabral is starting smaller, by creating a wound dressing that will promote healing for patients with chronic wounds, for example, foot ulcers in diabetic patients.

Alongside this, Mina Rajabi, a PhD student in Cabral's lab, is working on a bone healing scaffold. Instead of using metal rods or pins this scaffold will encourage the bones to knit together and grow, before naturally degrading inside the body.

Rajabi and Cabral' fill Claire Concannon in on the potential of 3D bioprinting and how to choose the right materials, add-ons and structure for what you are trying to make.

Dr. Cabral's work was funded by Health Research Council of NZ Explorer Grant and a Lottery Health Research Grant.

Designing better medical devices

When the pressure's on and someone's airway is blocked, sometimes the only solution is an emergency tracheostomy.

But it can be a time consuming procedure with many steps and the risk of complications.

Now a University of Canterbury student has designed a new, simplified version that has halved the time it takes to perform a tracheostomy

Katy Gosset talks to Student Engineer of the Year, Francis Pooke, and looks at the bigger picture of how bioengineering can transform health care…

Go to this episode on rnz.co.nz for more details

Stories of physics research in Antarctica - into, under, and from within the ice. Claire finds out about measuring sea ice thickness and supercooling. Katy Gosset learns how scientists detect neutrinos from outer space.

The frozen continent of Antarctica is defined by its snow and ice. On land, freshwater ice sheets kilometres thick sit on top of rock. In the ocean, an area of sea ice twice the size of Australia forms each winter, to break up in summer.

Though distant and intangible to most of us, what happens to Antarctic ice has global impacts, hence researchers want to find the best ways to monitor it in a warming world.

But for others, Antarctic ice presents unique and ideal conditions to catch glimpses of elusive subatomic particles from space.

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How thick is that ice?

What happens to Antarctic sea ice affects the global climate and ocean circulation. But measuring its thickness is hard.

Not only does it change every year, but in some places, it can change every day. On top of that, it forms over a massive area, much of which is inaccessible. Added to that, radar from satellites has difficulty finding the bottom of the ice because of the salt and a soft mushy layer that confuses it.

Instead, satellites can only measure the distance between the top of the snow and ice and the water. Which is maybe only 10 - 20 cm thick, on the most volatile patch of ocean on the globe.

So, tricky to do.

Emeritus Professor Pat Langhorne started her career trying to use radar to measure sea ice thickness. But when she and colleagues discovered that the salt and 'warm' mushy layer under the ice prevented this, she put that research aside and went on to investigate other aspects of sea ice.

Now, 35 years later, she has returned to this problem.

Langhorne and her collaborators now use electromagnetic (EM) induction to identify the bottom of the ice layer by flying a torpedo like piece of equipment, called Rosie, low over the ice.

This 'EM bird' gives more accurate measurements, which can be ground-truthed by drilling holes in the ice and checking the thickness manually. Eventually the plan is to use Rosie's measurements to calibrate the satellites. And, though retired, this is what excites Langhorne, and keeps her coming in to her office at the University of Otago Physics department.

Supercooling and crystals

But the ice in Antarctica has even more mysteries to it…

Go to this episode on rnz.co.nz for more details

Claire Concannon learns about experiments aimed at slowing Parkinson's Disease progression. Sonia Yee explores research into our perception of emotions in a mask-filled world.

The complexity of the human brain is astounding. Billions of brain cells or neurons forming circuits, with countless connections sharing information. This allows us to perceive the world around us, form complex thoughts, respond and move.

But it also makes it difficult for us to fully understand how the brain will react when things go wrong, or when situations change.

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Protein clumps and Parkinson's disease

Dr Victor Dieriks starts each day with the sound of the tissue culture hood alarm going off. This specialised enclosed bench has an air flow system that is constantly on, designed to keep the bench area as sterile as possible.

A Sir Charles Hercus Senior Research Fellow at the Centre for Brain Research in the University of Auckland, Dr Dieriks' daily routine includes changing the media of the dishes containing the cells he is working with, making sure they keep growing until he is ready to do experiments with them.

He works with a type of human brain cell called pericytes, grown from Parkinson's diseased brains that have been donated to the Neurological Foundation Human Brain Bank.

Dr Dieriks is investigating the protein clumps that are found within brain cells in Parkinson's disease sufferers. These clumps are made up of a protein called alpha-synuclein, which under normal circumstances has a role in helping neurons communicate with one another. But when certain environmental factors trigger this protein to form clumps, it can lead to problems.

The alpha-synuclein clumps are toxic to brain cells. Over time the clumps accumulate, exceeding the repair capacity of the brain, causing neurons to die. The clumps also spread throughout the brain, and when specific neurons in a part of the brain called the substania nigra start to die off this leads to the movement dysfunction characteristic of Parkinson's disease. How fast this progresses and what the specific symptoms are varies from patient to patient.

To add further complexity, the clumps can form different shapes to which the cells react differently, and which seems to result in these differences in symptoms and disease progression…

Go to this episode on rnz.co.nz for more details

The return of South Island kākā to the the Ōtepoti Dunedin area has been a bit of a rollercoaster ride. Claire Concannon hears about the tragedies and the triumphs, and the plans for what comes next.

The sun filters through trees as tūī and korimako compete for space at the sugar water feeders behind the Orokonui Ecosanctuary aviary. The giant bird cage contains three South Island kākā, waiting to be released, the hopes of many local groups resting on their feathered shoulders.

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Orokonui Ecosanctuary sits in the hills just north of Dunedin city. Three hundred and seven hectares of land cleared of pests and enclosed with a predator proof fence. It is a safe space for native birds such as South Island robin, tūī, kiwi and korimako, as well as for tuatara, skinks and geckos - watched over by conservation manager Elton Smith and ranger Kelly Gough.

In 2008 six South Island kākā were released into the ecosanctuary, the beginning of a plan to re-establish a population of these birds, long lost to their ancestral Otago home. Different to North Island kākā, their South Island cousins are also found in Ulva, Codfish and Steward Islands, Waitutu and Eglington valley in Fiordland and in Kahurangi national park. The population in Orokonui Ecosanctuary has been growing since that initial release, with 49 birds counted in the latest survey, but it has also suffered some setbacks. One of which was the infamous 'year of the stoat', in 2015, when several stoats managed to get inside the fence and raided the sanctuary for a few months before they could be caught and killed.

While supplementary feeding entices them to stay around the ecosanctuary, kākā don't pay much heed to the $2.2 million predator proof fence that they fly over, and the population has also suffered losses due to 'deaths by misadventure' on the outside. But through collaboration with a group of organisations, the team at Orokonui Ecosanctuary are hoping these latest three juvenile birds that have come from the Dunedin Botanic Garden aviary will bolster the numbers, and live safe and happy lives.

The South Island kākā breeding programme at the Dunedin Botanic Garden, in its eleventh year, continues to help kākā parents in their aviary to raise new chicks, to supplement those breeding inside the ecosanctuary. Aviary curator Alisha Sherriff is currently in charge of this programme and works closely with the Dunedin Wildlife Hospital to ensure the birds are kept healthy and well, and fit for release…

Go to this episode on rnz.co.nz for more details

Native mangroves in Aotearoa are expanding, putting them in conflict with some local communities & councils. A wade into the research about the value of mangroves & how they are managed.

Unlike many of Aotearoa's native plant species, our mangroves are actually doing great. Is that a problem, with mangroves clogging some waterways and taking over estuaries? Or is it just nature adapting, providing a great habitat for some birds and protection for our coastlines? Are mangroves the bad guys or just misunderstood?

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Finding footprints

Jacques de Satgé has spent three field seasons surveying for banded rail in mangroves. He has learned how to trap and GPS tag these cryptic birds. He has learned how to mark out quadrats in dense mangrove growth to survey for footprints, banded rail prey and vegetation. And he has also learned about the different properties of mud!

Jacques is part of the Human-Wildlife Interaction Research Group at Massey University, led by Associate Professor Weihong Ji. His research work is aimed at starting to fill a knowledge gap about how native birds, such as the banded rail, use mangrove habitats.

While New Zealand's mangroves don't have any obligate bird species - that is, a bird that relies solely on mangrove habitat - there is evidence that some birds do use mangroves for foraging and resting.

With hundreds of footprint surveys conducted at his four mangrove sites, coupled with GPS data from tagged banded rails, Jacques can now add what he has learned to the bigger picture of what we know about how birds use Aotearoa's temperate mangroves.

Mangrove expansion

Aotearoa's native mangroves can be found in the north half of the North Island, on the shorelines and estuaries found between Ōhiwa on the east coast and Kawhia on the west.

Mangrove is actually a term for a collection of tree species - those who can survive a twice-a-day dunking of sea water. Globally, there are many different species of tropical mangrove, and near the equator there can be mixtures of 20 to 30 species in just one stretch of coast. Right at the southern latitude limit of where mangroves can survive, in Aotearoa there is just one species of temperate mangrove (Avicennia marina subspecies australasica, known as Manawa)…

Go to this episode on rnz.co.nz for more details

Katy Gosset finds out how researchers investigate the plant penetration powers of myrtle rust. Claire Concannon speaks with the caretaker of a tropical forest and hundreds of butterflies.

From the lab to lockdown, stories of caring for the forest.

The destructive plant fungus myrtle rust is continuing its march across Aotearoa. Katy Gosset speaks to researchers studying its plant penetration powers in an effort to combat it.

Then, a visit to a balmy tropical forest in Dunedin with an essential worker who is caring for all the living things inside it.

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Fighting the plant pandemic

Since it was first found in Aotearoa in 2017, the invasive fungus myrtle rust has been spreading throughout the country, infecting native plants in the myrtle family - including pōhutukawa, rātā and mānuka.

Attacking the young leaves, shoot tips and young stems - myrtle rust results in deformed growth, affects flowers and fruiting, and can kill the plant.

Figuring out how to slow or stop this destructive fungus is what drives PhD student Sarah Sale. She wants to better understand the forces it uses to penetrate plants. To do this, she and her colleagues have gone to the microscale, and are using a unique device to do this.

The team is part of the Government's Beyond Myrtle Rust campaign and Katy Gosset visited them in the lab.

Unusually essential

When thinking about 'essential workers' Dr. Tony Stumbo's role is probably not the first that springs to mind. But the Tūhura and Living Environments Coordinator at the Otago Museum has an important job during lockdown - looking after the living things in the museum's tropical forest.

The tropical forest is a three-story enclosed space kept at an average temperature of 27oC. It is hot, humid, full of lush plants, and home to a terrapin (Shelly), as well as different species of birds, spiders and insects.

It is also a butterfly house. Each week hundreds of butterfly pupae are shipped to the museum from the Philippines or Costa Rica, to hatch in the quarantine room, before being released into the forest.

During lockdown, the careful protocols and checks that are involved in importing live, non-native species must continue, as well as the care of the pupae themselves. Tony explains his daily routine to make sure the plants, animals and butterflies are all being looked after.

Go to this episode on rnz.co.nz for more details

Two stories of looking to the skies. Claire Concannon joins a hunt for planets outside of our solar system. Katy Gosset reveals the results of the annual New Zealand Garden Birds Survey.

This week, Our Changing World looks to the skies. We start by gazing out to space, exploring how scientists find planets outside of our solar system, and what they hope to learn. Closer to home (just outside the window, in fact) we find out about an annual survey taking place in New Zealanders' backyards, one we can all get involved in!

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Looking for planets

We all learn about our solar system in school - the sun, our closest star, and its family of eight planets. The beautiful clear New Zealand skies reveal many, many more stars within our own galaxy - do they have a planet orbiting them? Their own planetary systems? And what can we learn from them about our own?

Since the first exoplanets (extra solar planets - planets outside of our solar system, going around other stars) were discovered in the 1990's, scientists have been trying to get a clearer picture of the diversity of planets that are out there, to learn more about how planets and planetary systems form.

But finding exoplanets is hard. Compared to stars, they are small, dim objects in the sky. In Aotearoa New Zealand the MOA project - Microlensing Observations in Astrophysics - has identified dozens of exoplanets since the telescope's 'first light' in 2006. The project uses gravitational microlensing to do this, whereby light from a distant star is magnified by something passing between it and the earth, giving a light signature that astronomers can analyse and interpret.

Claire Concannon speaks to Dr. Nicholas Rattenbury of the University of Auckland to learn how this works, what scientists are finding, and what the future of this area of astronomy will be.

The New Zealand Garden Birds Survey

In winter 2021 New Zealanders counted more than 260,000 birds across 133 species, in just over a week, providing key data that will be used to assess the state of the country's bird population.

Running since 2007, the latest results from the New Zealand Garden Bird Survey show more sightings of fantail, or pīwakawaka, tūī, and kererū since 2009.

Meanwhile the silvereye population, which had been declining, appears to have stabilised.

But the survey, based on one first conducted in Britain, only exists because thousands of citizen scientists take to their gardens every year to help count the birds.

Katy Gosset joins them and finds the project also brings other benefits for participants.

Go to this episode on rnz.co.nz for more details

This week, how information flows in the cell from DNA to proteins, and how scientists have tapped into this to enable a new way to make vaccines using messenger RNA.

For hundreds of years humans have triggered the immune system on purpose, in advance, to prepare it for deadly invaders. Smallpox, measles, typhoid, and today, Covid-19.

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We can trace the history of vaccination back to early days of smallpox inoculation - to China & India in the 1500s (maybe much earlier). They scratched matter from smallpox sores into the arms of people in an attempt to prevent future fatal infections. It was basic, but it was the start of a science saving millions of lives today. Over the years, vaccine technology has become more refined, and now, we have added one more way of making vaccines, using messenger RNA.

Information flow in the cell goes in one direction - from DNA to messenger RNA (mRNA) to protein. The genes in our DNA encode instructions to build the protein machines that make our cells function. DNA is the store of this information and is kept in a small compartment called the nucleus. The ribosomes, the cellular machinery that makes proteins, are found in the main part of the cell - the cytoplasm. Messenger RNA then is the intermediary, it is a temporary copy of genes from the DNA, which can move to the cytoplasm to be translated into a protein.

While previous vaccines have directly used dead or crippled virus or bacteria - or viral or bacterial proteins or toxins - to trigger an immune response, mRNA vaccines work on an elegant system of sending in a message containing instructions for the cell to make a specific protein. Once the cell makes this protein some of it is presented on the outside of its cell membrane for the scanning immune system cells to test. Once it is recognised as foreign it triggers an immune response - antibodies against the protein are created, meaning the immune system is primed and ready to go should infection ever occur.

When Pfizer BioNTech announced in November 2020 that their new mRNA vaccine against Covid-19 infection had shown success in its Phase 3 clinical trial it was certainly big news for a world gripped in a pandemic, but also a leap forward for this field of research. The Covid-19 vaccines made by Pfizer and Moderna are the first mRNA vaccines to be approved for public use…

Go to this episode on rnz.co.nz for more details

How do you find a tiny robin in a whole lot of forest? Researchers have been tracking the movements of forty North Island robins, or toutouwai, that have been reintroduced to a large reserve area near Palmerston North. Claire Concannon finds out how these Massey University researchers monitor them, and what they are learning.

The sound of static crackles in the damp bush. It's a common background noise for many bird conservation researchers following the birds they are busy trying to save. 'You start dreaming about it' says Postdoctoral Fellow Dr. Zoe Stone, as she walks through the Turitea Reserve holding an aerial, with a receiver slung across her chest.

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Zoe is tracking the movements of the forty toutouwai, or North Island Robins, that sing and peck their way through life in a 4000 hectare area of bush on the outskirts of Palmerston North. The toutouwai came from Bushy Park Tarapuruhi Forest Sanctuary near Whanganui and have been re-introduced to the area through a collective effort involving Palmerston North City Council, the Rangitāne o Manawatū iwi and researchers from Massey University, including Zoe and her colleague Professor Doug Armstrong.

While toutouwai do very well in fenced predator free reserves and offshore islands, re-introductions on the mainland have not had the same success.

But that's all about to change. After decades of work on predator-trapping, bird behaviour and tree flowering and seeding, conservationists are moving towards re-introducing native birds back into mainland forests. This toutouwai translocation is the ideal opportunity for researchers to gain helpful insights towards that goal.

They want to know what happens when you bring birds back to a large area like Turitea. Do they stay close to the release site? Or do they disperse more widely? What kind of area needs to be controlled for predators to keep them safe? How do they react to 'edges' like farmland?

Each toutouwai has been fitted with a transmitter that broadcasts a signal on different radiowave frequencies. These signals can be detected by flying an aerial-equipped drone over the forest, or, the traditional way, by Zoe hiking through the bush and scanning for birds.

Zoe & Doug hope that what they learn will inform future bird re-introductions, and help with the overall larger goal of getting More Birds in the Bush.

To learn more:

Watch the Palmerston North City Council video Robins Return about the toutouwai translocation.

Zoe spoke with Karyn Hay about toutouwai for the Lately show in July 2021…

Go to this episode on rnz.co.nz for more details

How do you get in the zone to achieve your very best in an activity? And does a cheering crowd help? This week, two stories about the psychology of performance - the advantages of being at home, and how to find your flow.

They say that sport at the very highest level is won and lost in the "top two inches"; it's as much about getting your mind in shape as it is your body. The pressure to perform at an event like the Olympics or an All Blacks' test is immense - the expectant crowd, internal pressures, and intensity of the moment can undermine years of hard work.

If you want to deliver, how can you get your mind in the right place? This week, two stories about sporting psychology.

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Home Game Advantage

The 2020 Tokyo Olympics have been strange in many ways, not just the excess of hand sanitiser. Empty stadiums, empty stands, empty swimming pools. How does the lack of people impact athletes who are accustomed to regular cheering, who might in fact thrive on it? Especially the Japanese athletes who would have expected to have had the sort of boost you only get competing in front of a home crowd.

Research form the University of Canterbury is probing the impact of crowds and match officials on 'the home game advantage'.

While most teams rise to the occasion when the crowd roars its support, there can be other outcomes too.

Katy Gosset hits the sports field to find out more.

Finding flow

As rock climbing makes its Olympic debut, a Dunedin-based researcher is looking into the importance of being "in the zone" when doing these types of adventure sports.

Patrick Boudreau is studying "Flow and Clutch" - they're the technical terms for optimal mental states. While flow state is about 'letting it happen', so that the activity enjoyable and motivating, clutch can be thought of as 'making it happen', something that is vital when you're doing an activity where a wrong move could be disastrous.

But both of these psychological states have wider applications too, in the office as well as on the sports fields. Claire Concannon catches up with Boudreau at a bouldering gym to talk about his research work.

Go to this episode on rnz.co.nz for more details

Researchers from the University of Waikato talk about Relative Energy Deficiency in Sport (RED-S) - a condition in which athletes don't take in the right amount of calories to do the exercise they are doing. Katie Schofield & Holly Thorpe explain why the problem is much more complex than just calorie intake, and why it is important to research this condition in a multidisciplinary way.

Watching the Olympics from the safety of the couch with snacks in hand, it's hard to imagine what athletes go through to reach the pinnacle of their sport. We can find ourselves watching and wondering, "What does it take to be so fit? What's the price of that sort of success?"

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For some athletes it's meant almost starving themselves to achieve their desired body weight and goals. In the 'no excuses', 'no pain, no gain' world of elite sport, hunger for success sometimes means actual hunger, but this can have devastating consequences to the athlete's performance and health.

Now, athletes are starting to speak out and researchers, like Dr. Katie Schofield at Waikato University, are turning their attention to RED-S, or Relative Energy Deficiency in Sport.

Schofield, a professional track cyclist for four years, was diagnosed with the condition herself, and was forced to take a year out of the sport to recover. What she learned on her personal journey inspired her to return to research RED-S for her PhD.

All of us need a baseline amount of energy to keep our bodies ticking over. But when elite athletes - or even over-enthusiastic amateurs - are expending so much energy in their training and not putting enough in, the deficit can do serious damage. It impacts not just the athlete's performance, but also their mood, immune system, hormone levels and bone health, among others.

For example, RED-S can lead to lower oestrogen, causing disruption in the menstrual cycle and loss of bone strength. If left unchecked this makes the athlete vulnerable to future fertility issues and stress factors. The warning signs can be missed amidst a tough training schedule and the stigma against not wanting to look weak; it's often not until bones are broken or other more serious injuries occur that people realise something more is going on…

Go to this episode on rnz.co.nz for more details

Scientific research can be thought as on a spectrum from blue sky to applied - this week, two stories that span this. Claire Concannon learns about a blue-sky research project on bacterial evolution while Katy Gosset watches testing of a new system of base isolation designed to help homes during earthquakes.

Using science to solve an urgent problem - like, say, developing a vaccine in the midst of a global pandemic - is pretty satisfying. But knowledge only moves forward because researchers build on what is already known, the idea of 'standing on the shoulders of giants' to see further. If no-one has done the basic research into how cells and immune systems work, you have nowhere to start.

So at one end of the science spectrum you have blue sky research, which asks basic questions about the world, without knowing what the application of the knowledge gained might be. At the other, is applied science, specific research aimed at fixing an immediate problem.

This week, two stories that span this spectrum.

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Blue sky thinking

Professor Craig Cary from the University of Waikato has been to the most extreme environments around the world - from deep sea, super hot and toxic hydrothermal vents, to the ultimate in dry and cold on Mount Erebus in Antarctica. His quest? To discover new bacteria that live there. He is fascinated by the microbial life that calls these extreme places home and how have they adapted to survive and thrive in these hostile conditions.

But for his next project, to find the bacteria he needs, he won't be boarding a plane or boat, but instead, asking a supercomputer to find it for him from a vast array of genome databases.

Craig is part of an international group of researchers who have been awarded a Human Frontier Science Program grant to investigate the evolution of the flagellum of a group of bacteria. The flagellum is the tiny protein motor that allows bacteria to move and find the nutrients they need to multiply. It's a critical job. Craig and his colleagues will be investigating whether flagella evolution always involves small step-wise changes, or, whether sometimes large protein components are incorporated that allow leaps forward in flagellum evolution.

Its blue sky research - high risk, possible high reward, but with no idea right now of what the application of any knowledge to come out of the project might be.

Base isolation for homes

When earthquakes strike, we're often just relieved to have survived. But Canterbury's deadly quake sequence has shown damaged homes can also cause years of disruption, stress and expense…

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On this week's Our Changing World - how songbirds learn their song, and how researchers in the Southern Hemisphere are trying to correct a long-standing male bias in the songbird world.

The traditional view in the songbird research world is that male birds sing elaborate songs to attract a mate, while females stay silent. That's just the done thing. Or so it was thought. Now Southern Hemisphere songbird researchers, such as those in Massey University, Auckland, are challenging this.

Songbirds, also known as the passerines (a massive group of 5000 or so species of bird including tūī, kōkako, stitchbird as well as wrens, tits and sparrows) must learn their song, just as a human baby learns language from those around them.

Professor Dianne Brunton is interested in the cultural evolution of songbird learning - how and why songbirds learn from each other, and how songs change with time and movement of birds. By studying the evolution of song changes in North Island tieke when they were translocated to different offshore islands, Dianne and her colleagues were able to investigate how saddleback song dialects change and how quickly they can innovate.

In tieke only the males birds sing, but Dianne is also determined to shine a light on female song, which is more common in the Southern Hemisphere. Her research, along with that of Dr. Michelle Roper and Dr. Wesley Webb, who work alongside her, has focused on female korimako or bellbird song. By recording individual bellbirds and breaking their song down into parts or 'syllables' the group has been able to show that male and female bellbirds are singing distinct songs - they have different language dialects.

Instead of a larynx, which allows humans to speak, birds have a syrinx. It is double barrelled, allowing them to make more complex sounds. They have identified differences in the physical structure and development of the syrinx in male and female birds that might allow them to sing these different song. Now Michelle is investigating the different syrinx structures in a family of passerines called the honeyeaters, which in New Zealand includes bellbirds and tūī.

Dianne, Michelle and Wesley explain how they study birdsong, what studying birdsong evolution can tells us and how their findings are disrupting the traditional view of female birdsong.

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To learn more:

Visit the Avian Acoustics Research page. Dianne, Wesley & Michelle also use Twitter to talk about their research work, you can follow them at @bellbirdsong_nz @wesleythewebb and @Musedmichelle,…

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Mathematical equations can help us get new perspectives, but sometimes can be difficult to understand. This week, one story about how maths has helped the understanding of a enigmatic quirk of heart rate control and another on how crafts can be used to better understand maths.

Mathematical rules and equations can help us get new perspectives on our world, but sometimes can be difficult to comprehend. This week, stories about how maths has helped the understanding of a enigmatic quirk of heart rate control and how crafts can be used to better understand maths.

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A new perspective

Alona Ben Tal was sure that her mathematics experiment would be a simple check to confirm an existing idea about heart rate control. When the modelling proved that the existing theory couldn't be true, it instead uncovered new insights into how heart rate is regulated during breathing.

An Associate Professor at the Mathematics Department at Massey University, and a member of the Manaaki Mānawa Centre for Heart Research at Auckland University, Alona uses mathematical modelling to get a new perspective on puzzles about how the heart and lungs work and interact.

Getting crafty about teaching maths

For some it's the scary subject at school but more New Zealanders are rediscovering maths, thanks to a crafty approach by local mathematicians.

Maths Craft uses creative skills such as knitting, crochet and origami to demonstrate the mathematical patterns and concepts that are all around us.

Katy Gosset visits one of the group's festivals in Christchurch.

Want to listen to more?

Our Changing World has a great back catalogue of mathematics related episodes, some are listed here.

For Maths, models & insights into the coronavirus pandemic Alison Ballance spoke with Associate Professor Alex James about creating mathematical models for complex systems.

What bird is that? is about collaboration between mathematicians and biologists to develop computer software that can recognise bird calls.

In The significance of statistics University of Otago science communication student Ellen Ozarka, explores the funnily named p-value or probability-value.

Maths professor Mark McGuinness is featured in a short episode about muesli and sea ice (2016) as well as one about lumpy volcanic eruptions (2013).

To find more, use the search tab on the home Our Changing World page and type in maths.

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Researchers at the Auckland Bioengineering Institute are working on what they hope will be the first New Zealand designed Class 3 medical device - a pressure sensor for the brain, to help people with hydrocephalus. The team explain the sensor design, how it works and how they test it.

Feeling the pressure

Professor Simon Malpas and his lab group are dedicated to figuring out how to detect pressure in the brain; pressure caused by a build-up of fluid, a condition known as hydrocephalus. But it's pressure of another kind that gets Malpas and his team out of bed every morning and drives them on.

"We often meet patients and their families, and neurosurgeons as well, and a common thing they say is, if you can get this to work, its a game-changer for their lives"

Malpas has been interested in how you detect pressure inside the body for many years, but these days he and his colleagues at the Auckland Bioengineering Institute are trying to invent a new kind of implantable brain pressure sensor to help hydrocephalus patients. If they can, it will be the first New Zealand designed Class 3 medical device.

In New Zealand medical devices are rated by their potential risk from Class 1 (low risk) upwards. A Class 3 device is something that is long term implanted in the body, and is, therefore, high risk (for example, a cardiac stent).

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In hydrocephalus, a build-up of fluid around the brain increases the pressure, which can impact brain function, cause brain damage, and can even cause death. Normally, about half a litre of cerebrospinal fluid is produced in the body each day. The fluid flows through cavities in the brain called ventricles, and bathes the brain and spinal cord, before being reabsorbed into the bloodstream. An imbalance of this - either by overproduction of fluid, or blockage of the absorption back into the bloodstream - can result in a build up. While it can affect anyone at any age, hydrocephalus is most common in infants and other adults.

Before the invention of an implantable shunt to drain this fluid, hydrocephalus was almost universally fatal. But unfortunately, the shunts commonly used today are still failure-prone - in children the failure rate is 30 - 40% at one year and about 50% at two years. This can be due to a variety of reasons, including infection, blockage and mechanical failure. Some of the most common early symptoms of a shunt failing are nausea and headache, which can create a lot of uncertainty and anxiety amongst patients and their families. Is the headache they are experiencing due to shunt failure, or something more innocuous?…

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Two stories of Aotearoa New Zealand conservation communities who are caring for the flora and fauna in their backyards. Claire learns about the Catlins Bats on the Map project while Katy learns about saving scurvy grass.

Bats on the Map

One wall of the Owaka museum is covered with a giant map of the Catlins area, with stickers marking where bat detectors have been used to successfully detect pekapeka. The Catlins' Bats on the Map project has delivered on its aim. Literally.

It's opening night of a new exhibition telling the story of the project, and the crowd gathered is abuzz about bats, eager to share what they've learned. They've been investigating bat distribution in different areas at different times of year, as well as gathering data on the insects that they eat.

The Catlins is a large hilly forested coastal area straddling South Otago and Southland. It is home to one of Aotearoa's two native land mammals - the long tailed bat. Classed as nationally critical, any data that can be collected on the distribution of these bats can help with their conservation.

The Catlins community have been doing this work as a massive group effort. Volunteer groups run summer evening transect surveys each year with hand-held detectors. School children, their parents and their teachers have gone on overnight bat camps and have studiously hung out bat detectors in different areas around their homes, farms and schools, hoping to record the echolocation calls of bats as they hunt their prey at night.

The project has been supported by the South Otago Branch of Forest and Bird and by Curious Minds Otago Participatory Science Platform. Project leader, and South Otago Forest and Bird volunteer, Catriona Gower, says all the data collected will be analysed and fed in to the Department of Conservation work on pekapeka.

To find out more, the students in Catlins Area School have made a video about the project, or you can visit the project's Facebook page.

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Scurvy saviour fights for survival

It helped Captain Cook's sailors stay afloat in the 18th century but these days Cook's Scurvy Grass is fighting for its own life.

The sub-species of coastal cress was used by the English explorer to ward off the vitamin C deficiency, scurvy, but it's now considered a threatened species.

However the plant is being monitored and nurtured at the Charlesworth Reserve in Christchurch, alongside another conservation trial of a rare native butterfly…

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Claire Concannon meets a group of researchers who are determined to do the best science they can, to try to help the people they love.

Emeritus Professor Warren Tate hadn't heard of the disease that would become such a big part of his life until his 14 year-old daughter, got glandular fever. Instead of recovering normally from this viral infection, her fatigue, pain and noise sensitivity symptoms worsened, and, months later, after ruling out everything else, she was given the diagnosis - Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS).

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Looking for answers

Other scientists in Warren's lab also have a deeply personal connection to the research topic. Anna Blair, who is interning at lab, has ME/CFS herself. Jemma Ellie, who is investigating cellular changes during the post exertional malaise response (a term for a type of exhaustion ME/CFS sufferers feel after doing strenuous exercise or thought), has first-hand experience of what the disease can mean for families.

The medical history and background to ME/CFS is convoluted, and includes a fair share of controversy and scientific dispute. ME/CFS is a chronic, multi-system disorder that has proven difficult for scientists to unravel.

Warren and his biochemistry research lab group in the University of Otago have been trying to help solve this puzzle by looking for changes at the DNA and cellular level. This could help them figure out what causes the disease or help them identify a specific biological marker that could be used for diagnosis.

Recently, they looked for changes in DNA and proteins of immune cells taken from the blood of ME/CFS patients. In 2020 they reported significant differences between with regards DNA methylation and some protein levels between the patients and the healthy controls (samples taken from people who don't suffer from ME/CFS). Because DNA methylation (the adding of a little molecule called a methyl group to DNA) is known to change the expression of genes (that is, which genes get read, and the instructions in them are used to make a protein) it is likely that this difference is impacting gene expression in these patients. When they looked closely at the changes in protein levels in ME/CFS patients (some proteins were there in increased amounts, some in decreased amounts) they found that the careful balance of proteins related to the mitochondria was disrupted…

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Two stories about science pathways - Katy Gosset heads to the University of Canterbury STEM careers fair to find out what the future might be for science students, while Claire Concannon learns about the weird world of parasite life cycles.

Just where might science lead? This week, two stories on the winding paths that science can take you on.

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Our Changing Careers

Meet Dr Sarah Kessans. As an undergraduate she started off in plant biology. For her PhD she trialled an HIV vaccine at Arizona State University. Now she's at the University of Canterbury teaching product design and developing space craft.

Tomorrow's challenge? Who knows!

Our world is changing and, with it, our careers. And science jobs will be among the first to evolve.

Katy Gosset visited a University of Canterbury Careers Fair for STEM (Science, Technology, Engineering and Mathematics) students to find out what the future might hold.

For Kessans, much of the appeal of her diverse career lay in the opportunity to explore new concepts and translate them to business models. "Getting to work with people from all sorts of different disciplines and to develop things that are not things yet, to design entirely new sectors of industries. It's just incredible," she said.

Kessans urged her students to seize every opportunity by attending public lectures and meeting academics from different fields. She believed it was those interactions that would help create new industries.

"You never know where that next innovation is going to come from so a lot of this innovation is sort of the serendipity of new connections. So the more our students can develop new connections across different industries, the more opportunities they're going to have for both their education and then their future careers."

Finding your niche

Jeff Doherty moved from Canada to New Zealand to follow his interest in how parasites manipulate their hosts. He is at the end stage of his PhD studying hairworm parasites. Like other parasites they have a complex life cycle, in fact more interesting than most, as it involves the parasite moving from a water-based insect host, to a land-based insect, which somehow is fooled into going to the water to allow the hairworm to complete its lifecycle…

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In her final trawl through the audio archives, Alison Ballance heads to Putauhinu Island, a southern sanctuary for rare birds.

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Alison Ballance revisits a favourite story from the archives: southern island sanctuary for rare birds.

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Alison Ballance revisits a 2013 feature on kauri dieback disease and talks to Nick Waipara to find out how the northern kauri forests are coping with the disease in 2021.

Alison Ballance's archive choice this week is about kauri dieback disease - she goes back to a feature recorded in 2013, and then hears from Nick Waipara about the situation in 2021.

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For more information head to the original 2013 feature: kauri dieback disease.

For further research into kauri dieback disease:

Kauri dieback and how microbes sense the world

Hunt for kauri that are resistant to kauri dieback disease

For stories on kauri's role as a keeper of past climate records:

Giant kauri trees and climate change

Climate data from kauri trees

Swamp kauri and past climates

Time travelling with a climate scientist

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Alison Ballance revisits a 2013 story about kauri dieback disease and gets an update of the disease's impact in 2021.

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In this week's retrospective, Alison Ballance revisits an ocean acidification special feature called The Acid Test.

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Alison Ballance's foray into the vaults finds a feature on ocean acidification, The Acid Test and adds a 2021 update.

Alison Ballance revisits a story about ocean acidification, which has been described as 'global warming's evil twin.'

She also catches up with NIWA marine biogeochemist Cliff Law to discover what we've learned in the past decade about the growing impact of carbon dioxide on the acidity of the world's seas.

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The Acid Test - a feature on ocean acidification, first played 2010.

Our Changing World has made a number of stories about climate change and its impact on the world's oceans:

Acid test for coastal seas

Winners or losers? Antarctic starfish and climate change

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2020 Prime Minister's Science Prize winners talk about their research and teaching.

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There are some familiar names as well as some new faces among the winners of the 2020 Prime Minister's Science Prizes.

There are some familiar faces as well as some new names among the Prime Minister's Science Prize winners this year.

Two of the five prizes are awarded for efforts to better understand and communicate the Covid-19 pandemic.

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The five Prime Minister's Science Prizes are New Zealand's most valuable research awards. Awarded annually, they are worth nearly $1 million.

A real team effort

The team prize, worth half a million, has been awarded to a consortium of 24 researchers working together in the field of complexity science as part of Te Pūnaha Matatini, a Centre of Research Excellence.

In early 2020, director Shaun Hendy saw that there was a gap in providing the New Zealand Government with the data science it needed to make informed decisions about responding to the Covid-19 pandemic.

He assembled a multi-disciplinary team that developed a series of new mathematical models and ran a multitude of different scenarios to inform the unique situation that New Zealand found itself in.

The team has done modelling work and analysis on a wide number of areas, including hospital capability, contagion rates and likely disease spread, virus genomic tracing, contact tracing, and vaccination.

The results of this work were translated for use by the government policymakers and front-line operators and helped inform the government's response to the Covid-19 pandemic.

Among other actions, this led to the government's 'Go Hard and Go Early' mantra that resulted in stringent lockdowns - both the country-wide lockdown beginning in March 2020 and the tailored Auckland lockdown beginning in August 2020.

Hendy and University of Auckland colleague Siouxsie Wiles have both been active spokespeople on the subject of Covid-19.

Hendy says the team's work is not finished yet. He adds "we will be leaving our tools, making them open so they can be maintained in perpetuity, so next time we meet an infectious disease crisis they are there for people to use."

Technology a winner in Prime Minister's Science Teacher Prize

Sarah Washbrooke, from Remarkables Primary School in Queenstown, is the first technology winner of the Prime Minister's Science Teacher Prize.

She uses a hands-on approach to teaching technology which is so engaging that her students often remain unaware of the depth and range of learning they are doing…

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Alison Ballance digs into the Our Changing World archives for an Antarctic blast from the past with Voice of the Iceberg 2: Revelation.

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Alison Ballance digs into Our Changing World's Antarctic treasure chest and finds part 2 of Voice of the Iceberg.

Alison Ballance made two trips to Antarctica during her 12 years as host of Our Changing World. She also visited 'virtually' with an award-winning podcast series that celebrated the sounds of icebergs.

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In this week's icy retrospective, Alison revisits the Voice of the Iceberg series, in which artist Joseph Michael and his team recorded the characters and sounds of icebergs in Antarctica.

In Part 2: Revelation, the varied personalities of different icebergs began to reveal themselves.

Visit the Voice of the Iceberg webpage to see Joseph Michael's stunning photos.

Voice of the Iceberg won Best Creative Feature at the 2018 NZ Radio Awards.

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Alsion Ballance revisits a story looking at the complexity of the 2016 Kaikōura earthquake.

After more than 12 years as host of Our Changing World, Alison Ballance is diving into the archives in search of some golden oldies.

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This week's theme is 'the big one'.

The magnitude 7.8 Kaikōura earthquake in 2016 had a big impact on the landscape and communities of North Canterbury and Marlborough.

It also shook up the science community, which responded quickly to study and understand what was described as a 'very complex earthquake.'

Check out the original story from May 2017, to see photos and read more about the earthquake.

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In this week's retrospective, Alison Ballance looks at the 'big ones': a big earthquake in Kaikōura in 2016 and a big science effort to understand it.

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With more than a thousand conservation stories under her waterproof parka, science journalist Alison Ballance is retiring from RNZ's Our Changing World programme.

Alison Ballance has dived with 17 different species of shark, she's drilled down into the ice of Antarctica to capture the symphony of Weddell seals, she's become the kakapo "aunty".

But after telling more than 1,000 stories, the voice of RNZ's science, environment and nature programme Our Changing World, Ballance is retiring.

"My work life balance gets a bit blurred because I can go to a remote island and help out on a diving expedition and I can be recording for Our Changing World and I might be blogging for Auckland Museum, when I went to the Kermadecs and I'm diving and it's all just a big blancmange for me," she says.

Today on The Detail Ballance talks to Sharon Brettkelly about her career that was inspired by a four-month trip to the sub Antarctic islands to study feral sheep for her master of science. She didn't really want to study the sheep but she desperately wanted to go to the southern tip of New Zealand.

"I've kept going back, sometimes there's decades between my trips but once you get down there it just gets into your system."

For five years she persistently contacted the Natural History New Zealand documentary team in Dunedin asking for a job, before they finally recruited her. The job took her to Mongolia, Ecuador and Russia but the "incredible" Galapagos Islands remain her top overseas experience, continuing her "obsession with seabirds and with islands and with natural history".

For more than 12 years Ballance has taken OCW listeners to far flung places to tell science and nature stories.

"I'm a tramper from way back, I'm a camper from way back so I don't mind how basic the living conditions are, if it's an opportunity to join people - and there are some very generous and amazing scientists in New Zealand who've been willing to have me along - I don't mind how crude my living situation is if I've got an opportunity to tag along and tell stories."

The rugged and famously windblown sub-Antarctic islands have a special place in Ballance's heart but they are also the location for one of her toughest living and working experiences.

"The living conditions were very difficult because there had been a massive rainfall event, there'd been these huge slips which had shunted the one small hut on the island about 20 or 30 metres and it needed to be fixed…

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Alison Ballance looks back at the 1,000+ stories she has made, and revisits stone-eating spotted shags and urban eagle rays

As Alison Ballance prepares to stand down as host of Our Changing World, she looks back at the more than 1,000 stories she has made and revisits some favourites.

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This week's theme is wildlife spectacles 'under our noses.'

Stone-eating spotted shags turn up at dawn on Tata Beach, in Golden Bay - and Alison headed there in 2013.

In 2015, she went in search of urban eagle rays in Wellington's inner harbour.

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Alison Ballance plays favourites from the archives - stone-eating spotted shags and urban eagle rays.

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Seabird species are being reintroduced to Mana Island to help restore the ecology of the island.

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The story of a seabird translocation to Mana Island, involving fluffy white-faced storm petrel chicks, artificial burrows and sardine smoothies.

'Bringing back the seabirds' is the rallying call for conservationists working to restore Wellington's Mana Island.

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The latest seabird to be brought back to Mana Island is one of New Zealand's smallest - the white-faced storm petrel.

A handful of these sparrow-sized birds already breed on the island, and the Friends of Mana Island are hoping the 260 chicks they have rehomed to the island in the past three years will soon give this number a welcome boost.

The new arrivals hail from Rangitira, in the Chathams, which is home to a thriving white-faced storm petrel breeding population.

They were collected as late stage chicks, and translocated to Mana Island via crayfish boat, plane and helicopter.

Upon arrival, each chick was fed and transferred to an artificial burrow. The burrow comprises a dark, quiet nesting chamber with a soft floor of dry leaves.

A tunnel made from drainage coil gives access to the world outside, although for the first few days the chicks are barricaded inside to prevent them wandering outside and getting lost.

A team of volunteers from the Friends of Mana Island, led by seabird expert Cathy Mitchell, look after the chicks for several weeks until they develop their full adult plumage and are ready to fledge.

Once a day, each chick is collected from its burrow and taken to the classic caravan that serves as the dining room.

The chick is weighed to check that it is on a perfect trajectory - adding precious grams until the final week before departure, when it needs to slim down to flight weight.

A wing measurement gives an indication of flight readiness - wing feathers grow up to 3 mm a day until they are about 50 mm long.

Health and Plunket check complete, Cathy and sidekick Shane Cotter give each bird its once daily meal - 7 ml of sardine smoothie delivered directly into the crop via a syringe and a soft feeding tube.

A sardine smoothie - made from finely blended sardines, fish oil, boiled water and a vitamin pill - mimics the natural diet of krill that parent birds feed their sole chick once a day.

Once Cathy judges that a chick is getting close to departure, the barricades on its tunnel come down. Then, if the chick is so inclined, it can explore down the tunnel during the night and check the outside world.

Depending on the chick, this stage might last a few days until one night it will leave the burrow and without any fanfare, simply lift off and fly away…

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Rare dolphins and whales were among the discoveries when the Far Out Ocean Research Collective surveyed the seas off Northland.

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The Far Out Ocean Research Collective has been surveying for whales and dolphins in the seas off Northland.

The offshore ocean may seem a flat featureless expanse, but underneath the surface there are interesting features, currents and water masses that make ideal habitats for a range of marine creatures.

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The Far Out Ocean Research Collective is a non-governmental organisation based in Paihia in the Bay of Islands.

Their goal is to survey the Northland offshore area to find out more about what is out there, where they are, and why they are there.

They are interested in marine megafauna - large marine creatures - and the seabird life that can be found offshore.

These types of offshore multi-day surveys are difficult to do. Travelling 20 - 50 nautical miles off the coast to observe and identify marine seabirds and creatures requires excellent weather conditions, a suitable vessel, and the right equipment and expertise.

This is why systematic surveying has not been done in this region before, and why we know quite a bit about New Zealand coastal or inshore marine species, but we lack data about those that live in this offshore environment.

For some species, the only information we have to date has come from strandings, rather than live sightings.

Since starting this work, the Far Out team has identified a wide range of marine life in this area.

Rarely-seen beaked whales, a previously unknown group of sperm whales, a juvenile whale shark and extremely rare dolphin species are just a few of the marine creatures encountered in this year's survey.

Alongside the visual surveys, the team also uses acoustic recordings to help them locate cetaceans that might be in the area.

A few species can be identified by their calls alone.

In the past few years, the scientists have collected incredible recordings of dolphins, false killer whales and pilot whales.

Their latest revelation is Northland sperm whale coda - a distinctive short patterned series of clicks, which sperm whales use to communicate with each other.

The Far Out team is planning further surveys and aims to build a map of this offshore area that integrates marine creature and seabird sightings, acoustic recordings and oceanographic data to give a detailed picture of what is out there.

Listen to the full episode to take a trip to the open ocean and dive deep into the acoustic world of sperm whales.

Far Out Ocean Research Collective

The Far Out Ocean Research Collective is a group of five marine scientists who set up a not-for-profit trust in 2017…

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Shaun Eaves talks about glaciers in the North Island and how evidence left behind by glaciers can help reconstruct past climates.

Talk about glaciers in New Zealand and most of us think about the great glaciers of the South Island - Fox and Franz Josef glaciers on the West Coast, and Tasman Glacier near Mount Cook.

But glaciologist Shaun Eaves has been pondering the forgotten glaciers of the North Island, and their past and future.

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Making a glacier

"The recipe for a glacier? You need cold temperatures and precipitation," says Shaun. "Snow is what the glacier wants."

Over time this snow compacts to become ice and eventually becomes large enough to be counted as a glacier.

Weather is critical to a glacier's survival.

"The colder the temperature, the less snow and ice you'll lose over the course of a year, particularly during summer."

"If you manage to keep some of your winter snow through the summer then that will add mass, and either sustain or start to build a glacier," says Shaun.

Sweet spot for a glacier

Glaciers occur at higher altitudes, where it is colder.

Shaun says they exist above a hypothetical line that glaciologists call the snowline, the altitudinal point where it is cold enough for snow to last year round.

Snowline in the South Island is about 2000 metres above sea level, so there are plenty of mountains higher than that where glaciers can form.

Although glaciers are born at higher colder altitudes, their ice can flow well below the snow line, almost to sea level in the case of Fox and Franz Josef glaciers.

Shaun says there are more than 3,000 glaciers in the South Island, although some smaller ones at lower elevations have disappeared in the past few decades.

The North Island's forgotten glaciers

He says that people may be surprised to know that there are still glaciers in the North Island, although it's difficult to put an exact number on them as defining exactly what a glacier is can be difficult.

"To me, a glacier is a perennial body of snow and ice that is deforming under its own weight," says Shaun.

Shaun says that physics shows that an ice patch needs to be at least 30 metres thick for it to start deforming.

There has not been any research to measure ice thickness on Mount Ruapehu, which at 2797 metres tall is the only North Island mountain high enough to rise above the snowline. The snowline is at about 2600 metres on the central volcanic plateau…

Go to this episode on rnz.co.nz for more details