In 2010 the Psa-V bacterial disease was found in a Bay of Plenty kiwifruit orchard. This was the beginning of a terrible ordeal for many kiwifruit growers. It devastated crops, resulting in the loss of hundreds of jobs, and hundreds of millions of dollars. But though it spread to some other areas in the North Island, it never made it across the Cook Strait. Claire Concannon learns about the science behind keeping this microbe out of Te Waipounamu.

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• The Plant and Food Research (today the Bioeconomy Science Institute) team who worked on science to help with the kiwifruit Psa crisis won the Prime Minister’s Science Prize in 2017.
• In 2012 Alison Ballance reported on the hunt for resistance genes so kiwifruit plants could be more resilient in the face of this bacteria.
• As In-Depth reporter Farah Hancock detailed earlier this year, 95% of the kiwifruit grown here are actually exported - an earner of $4.5 billion in 2025.

Guests:

• Falk Kalamorz
• Rebecca Manners, Bioeconomy Science Institute
• Dr Ed Morgan, Bioeconomy Science Institute
• Leanne Stewart, Kiwifruit Vine Health

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Ketamine was first developed as an anaesthetic, and today is taken by some as a party drug. But since 2000, research has emerged showing it is also helpful as a medication for some people with treatment-resistant depression. While initial studies used ketamine injections, recent research has shown the advantages of taking it in oral form. Now clinical trials are underway to determine if a New Zealand-developed ketamine pill is safe and effective enough to get the regulatory tick.

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In the Auckland suburb of Mt Albert there's a particular brand of doomsday prepping going on. Our Changing World visits the Bioeconomy Science Institute to meet some scientists figuring out how to build an army of Samurai Wasps just in case Aotearoa is invaded by Brown Marmorated Stink Bugs.

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• MPI's website has more detail on the Brown Marmorated Stink Bug and what to do if you find one.
• From December 2025 a new biosecurity inflight video about being vigilant is being played to incoming visitors.
• Our Changing World did a deep dive into the impact BMSB would have on New Zealand, back in 2019. 

Guests:

• Dr Gonzalo Avila, Senior Scientist - Biological Control, New Zealand Institute for Bioeconomy Science Limited
• Karina Santos, Senior Research Associate, New Zealand Institute for Bioeconomy Science Limited
• Dr Scott Sinclair, Manager, Operational Readiness - Plant & Environment, Biosecurity New Zealand

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Our Changing Word heads to Whangārei to speak to a Northland Regional Council scientist whose been using stormwater drains to estimate the scale of our plastic pollution problem. Plus, just outside Christchurch, one of New Zealand’s biggest lakes is home to the ‘canary in the coalmine’ of wetlands. The secretive and elusive Australasian bittern seems to be in trouble - how can we help?

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• Join Alison Ballance on a kayak across a lake to listen to some booming bittern crooners.
• Listen to the nine to noon interview with John Sumich about the 2025 Matuku muster.
• The research into microplastics was part of the AIM2 project, which was reported on in 2021 as part of the OCW episode ‘Unwelcome visitors’.
• Another source of microplastics is textile waste, but an international project is looking to a future where our clothes are fully biodegradable.

Guests:

• Richard Griffiths, Northland Regional Council
• Peter Langlands, Bittern Conservation – New Zealand
• Harry Caley, Department of Conservation

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In Dunedin the local tree crop association has been looking after a heritage apple orchard, but some mixed up labels meant they weren’t quite sure what varieties they had. A chance encounter at a public open day sets one young researcher on a scientific quest to ID them all. Plus, in a nursery in Rotorua, a propagation scientist is figuring out the best way to grow a native tree from cuttings.

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Take a (very) large egg, some insects (plus specially developed food), and a safe place to put on weight for a while. This is how you grow a kiwi, and improve wild survival rates from 5% to 65%. With over 2,600 hatches across their 30 year history, the National Kiwi Hatchery have a lot of experience under their belt, but there's always more to learn from our iconic national bird. Our Changing World visits the hatchery to learn how they combine conservation and eco-tourism to help grow kiwi numbers.

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• Operation Nest Egg has also been a great success for the rowi kiwi, the only remaining wild population of which lives in Ōkārito on the South Island’s West Coast.
• In July 2025 little spotted kiwi were found on New Zealand’s mainland for the first time in 50 years. Two chicks and eggs were subsequently brought to Willowbank Wildlife Reserve in Christchurch to allow them to get to stoat-proof weight.
• With a lot of help, and stoat trapping, brown kiwi are returning to the wilds of Wellington.
• Candling is also used to track kākāpō embryo development and egg fertility, learn more in episode 12 of the Kākāpō Files II podcast.

Guests:

• Emma Bean, manager of the National Kiwi Hatchery
• Carole Dean, kiwi keeper, National Kiwi Hatchery
• Rebeca Bothamley, tour guide, National Kiwi Hatchery

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In the Kaimai Mamuku ranges iwi-led conservation projects are tackling pests, removing weeds and planting natives to restore their whenua.

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• Jobs for Nature also supported an iwi-led wetland restoration project just outside Dunedin.
• In 2024 The Detail spoke to a number of Jobs for Nature supported projects that were nearing the end of their funding.
• The Turning Point video series followed some of the kaimahi working on different Jobs for Nature projects across Aotearoa.
• Country Life’s Dollars for Nature episode covered the government announcement about voluntary nature credits market. 

Guests:

• Louise Saunders, CEO of Manaaki Kaimai Mamuku Trust
• Mohi Korohina, Wairere Mahi project manager
• Hera Denton, GoEco

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A native species is taking over a jewel-in-the crown marine reserve. But what can be done?

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New Zealand is third in the world for the number of orbital rocket launches from our shores, sitting just behind the US and China. Phil Vine discovers some of the challenges raised by our push into the unknown and how it is changing the final frontier.

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• Through a science experiment on the ISS, New Zealand researchers have been taking advantage of the unique conditions in low earth orbit to investigate commercial opportunities.
• While New Zealand is well known as a place from which to launch rockets, we do not have a lot of our own hardware in space (the University of Auckland does have TPA-1 CubeSat). But that might be about to change.
• Tech bros turned space bros like Elon Musk are making big waves out in orbit. The latest news is that Musk is hoping to harness the sun through satellites to power AI data centres.
• The New Zealand government's biggest investment in an international space mission ended in failure last year after MethaneSAT, a satellite built to detect methane emissions around the world, lost contact.
• While there are challenges inherent in humans and their technology being in space, that’s not all that is going on. Scientists are keeping a close eye on an active black hole and bright lights have Northland locals turning their eyes to the skies.

Guests:

• Mark Rocket, CEO Kea Aerospace
• Dr Priyanka Dhopade, senior lecturer in mechanical and mechatronics engineering, University of Auckland
• Dr Tuana Yazici, space law expert

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We know there are issues with sustainability within the fashion industry - can science help create a better future? Claire Concannon visits the Bioeconomy Science Institute in Rotorua to learn how New Zealand scientists are contributing to a massive multi-national project aimed at shaping the textile industry of tomorrow.

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Learn more:

• UPWEARS has their own research project page if you want to learn more.
• Learn more about how the Bioeconomy Science Institute (formally Scion) is figuring out how to make new materials and products using bio-waste products rather than fossil fuels.
• The rise of synthetic fibres impacted the wool industry here in New Zealand, although some entrepreneurs and weavers are making it work for them.

Guests:

• Dr Yi Chen, Bioeconomy Science Institute, and UPWEARS
• Dr Robert Abbel, Bioeconomy Science Institute, and UPWEARS
• Sean Taylor, Bioeconomy Science Institute, and UPWEARS
• Louise Le Gall, Bioeconomy Science Institute, and UPWEARS
• Dr Kate Parker, Bioeconomy Science Institute, and UPWEARS

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