Our Changing World

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℃. 

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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…

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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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