Takahē were believed to be extinct not once, but twice. Today their population is just over 500 – still not a huge number, but big enough that new homes are needed for these flightless manu. The latest area to welcome takahē is the upper Whakatipu – in particular, the stunning Rees Valley. But threats remain and keeping on top of predator numbers is key for this comeback bird to survive and thrive in their new home.

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Guests:

• Chrissy Becker-Fifield, Southern Lakes Sanctuary.
• Additional thanks to Glen Greaves of DOC’s takahē recovery programme for background information.
• Also mentioned: the Routeburn Dart Wildlife Trust.

Learn more:

• November 2023 marked the 75th anniversary of the second time takahē were ‘rediscovered’. We spoke to Alison Ballance about her book about takahē, and her years of reporting on these birds.
• RNZ reported on DOC’s efforts to catch the stoat culprits that killed a number of takahē in the Greenstone valley.
• After decades of careful monitoring, DOC are stepping back from the Murchison Mountain’s population of takahē.
• Takahē have been spotted by trampers around the Shelter Rock hut deep in the Rees valley.

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Gas shortages, a reversal of the ban of offshore oil and gas exploration, and a government plan to double geothermal energy in the next 15 years… There’s been a lot in the news recently about New Zealand’s energy supply now and in the future. Claire Concannon speaks to researcher Dr Jen Purdie about our ongoing electrification of industry and transport, about our ‘dry year problem’, and what the future of supply and demand might look like in a changing climate.

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Guests:

• Dr Jen Purdie, Senior Research Fellow, Centre for Sustainability, University of Otago.
• Kirsty Johnston, RNZ In-Depth journalist

Learn more:

• Could nuclear fusion-generated energy be a way to help us power the future? Learn how New Zealand company OpenStar Technologies are trying to crack this.
• Read or listen to Kirsty’s recent reporting about what has changed in climate policies underpinning the Zero Carbon Act 2019.
• The coalition government has stated they want to use New Zealand’s Emissions Trading Scheme (rather than the GIDI fund) to help drive the transition from fossil fuels to other forms of energy, but as climate change journalist Eloise Gibson reports, there are issues with this plan.

References

• The 2025 Energy in New Zealand report came out in August 2025.

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New Zealand’s youth vaping rates are among the highest in the world. How did we get here and what will this mean for the future of our rangatahi? A 2018 court case paved the way for a loose regulatory start for vaping in New Zealand, and rapid uptake by those aged 14–24 in the years since has led to concerns that a new generation is now addicted to nicotine. New Zealand researchers are investigating how vaping affects our lungs, and the harms young people are experiencing in terms of social connections and mental health.

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More and more of us are reaching for low or no-alcohol beers. As the market grows, the options are also expanding – but brewing beer without alcohol fermentation presents a tricky puzzle. In traditional beer brewing the conversion of sugars into ethanol and carbon dioxide through yeast fermentation is a key part of the process. How can you get the same flavour into beer without it? A team at Victoria University of Wellington, including the head of research and development at Garage Project, have begun an interdisciplinary research project to address this. They’re hoping to develop a brand-new yeast strain, one that will recreate delicious beer flavours, but without the alcohol.

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Project Tongariro was established as a living memorial for five people who died in a tragic helicopter accident. Last November, the project turned 40 years old. Over those four decades, activities have expanded beyond Tongariro National Park and into the wider area, including urban restoration through tree planting and predator trapping. Claire Concannon visits the Taupō-based projects that Project Tongariro is supporting as they prepare for Greening Taupō Day – their biggest planting day of the year.

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Guests:

• Kiri Te Wano, CEO Project Tongariro
• Robyn Ellis, Greening Taupō and Predator Free Taupō
• Rachel Thompson, Kids Greening Taupō
• Heidi Pritchard, Kids Greening Taupō
• Celia Bocket, Wicked Weeders
• Zara, Jack, Taylor and Emily, students of Taupō Intermediate School

Learn more:

• Read the article that accompanies this episode: 40 years of Project Tongariro
• Project Tongariro are also involved in a number of restoration projects near Tūrangi, including removing willows from a wetland area.
• In Kirikiriroa Hamilton, a team are also focused on urban greening as part of the People, Nature and Cities project.
• Just outside Dunedin, the Halo Project has been working to provide a safe space for birds around the Orokonui fenced ecosanctuary, as the Country Life team learned last year.

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The battle on the frontlines of conservation continues around the motu. This week we head to the central North Island to join some of the staff and volunteers of Project Tongariro. Ecologist Nick Singers is coordinating the fight against the invasive grey willow that’s taking over a wetland area, while Shirley Potter is applying a ‘let’s get it done’ attitude to reforesting a patch of public conservation land near her home in Tauranga-Taupō.

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Guests:

• Kiri Te Wano, CEO of Project Tongariro
• Shirley Potter
• Nick Singers

Learn more:

• Read the article that accompanies this episode: 40 years of Project Tongariro
• Willow is an issue in many wetland areas where it binds up waterways and transforms the land. Just outside Dunedin, a team are using drone spraying to combat it near the Te Nohoaka o Tukiauau wetland complex.
• In the Rotopiko wetland complex, near Hamilton, the pest battle is a bit unusual: conservationists are concerned about the half a million sparrows and starlings that roost at night.
• The fight for the forest also continues on multiple pest fronts in the Catlins area in Otago.

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During World War II, sonar operators discovered a ‘false seabed’ that appeared to move upwards during the nighttime. In fact, the sound waves were bouncing off huge numbers of small critters. This daily movement is the largest animal migration on the planet, consisting of deep-water animals that hide in the ocean’s twilight then move to the surface after sunset to feed. By far the most abundant fish in this crowd are the lanternfishes. New Zealand researchers are investigating what impact lanternfish migration has on the life cycle of fish we like to eat, and how it may also play a huge role in the Earth’s carbon cycle.

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Guests:

• Professor Jeff Shima, Victoria University of Wellington
• Alisha Gill, Victoria University of Wellington
• Niamh Smith, Victoria University of Wellington

Learn more:

• Read the article for this episode: Lanternfish: small fish, big impact
• Below the twilight zone, in the deepest parts of the worlds’ oceans, including in New Zealand waters, scientists continue to discover new critters.
• The deep ocean makes up the majority of the living space on our planet, where life down there has evolved to cope with the pressure, cold and darkness.
• The Southern Ocean absorbs a huge amount of carbon, but scientists are concerned that may change as the planet warms.

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For a long time, nuclear fusion was viewed as a powerful, but unachievable, energy source, because the technological challenges were just too great. But recent advances, particularly in the development of powerful magnets, have reignited the race to create the world’s first efficient nuclear fusion powerplant. Claire Concannon visits one private company just outside Wellington who have joined the nuclear fusion effort, with a unique approach they believe might be the key.

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Guests:

• Dr Ratu Mataira, Founder and CEO of OpenStar Technologies
• Emily Hunter, Lead Engineer Cryogenics and Docking, OpenStar
• Thomas Berry, Deputy Direct of Plasma Science, OpenStar

Learn more:

• Read the article that accompanies this episode: Could a Kiwi company crack nuclear fusion?
• Kim Hill had a lengthy and fascinating interview with Dr Ratu Mataira in 2023 on RNZ’s Saturday Morning show. He also spoke with Alexa Cook on Morning Report in 2024 after OpenStar achieved ‘first plasma’.
• In 2023 Our Changing World played an episode of the ABC’s Strange Frontiers that went inside the nuclear fusion reactor ITER.
• Learn more about the simplest element, Hydrogen, from RNZ’s 2019 Elemental podcast.
• The Royal Society of New Zealand has a series of videos on Ernest Rutherford’s scientific discoveries including radioactive decay and half-life, and splitting the atom.

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