Nobody knows how many feral cats roam New Zealand, but estimates are in the millions and they’re a major threat to our native species. They've infiltrated almost every landscape, from coasts, to farms, to National Parks like Fiordland. Plus they’re wily and trap-shy, making them a tricky predator to tackle. RNZ's In-Depth reporter Farah Hancock speaks to some people on the front lines of the battle against feral cats.

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In this episode:

00:00 – 00:59 Introduction to bonus episode
01:00 – 03:24 Background to feral cat problem

03:40 – 10:30 Playing ‘poos clues’ & trapping cats with hunter Victor Tinsdale

10:40 – 15:00 Daniel Cocker on how cats are threatening the dotterels on Rakiura

15:20 - 16:20 Farah explains how secondary poisoning works

16:30 – 19:42 Objections to 1080 use on Rakiura, and efforts to address these

20:18 – 24:08 Brad Windust with cat poo smelling dog Wero

24:09 – 24:44 Credits

Learn more:

• Read the series of articles and see photos on the RNZ Feral webpage.
• In 2023 OCW spoke to ‘Dotterel Dan’ about the plight of the pukunui, and a tagging study aimed at identifying exactly where they nest on Rakiura.
• In the Catlins, Forest and Bird pest control officer Gavin Whiteis also battling trap-smart feral cats. While in the Wye valley near Queenstown, the Southern Lakes Sanctuary is hoping that new AI tech will help in the battle.
• Kākāpō were moved fromRakiura because of predation by feral cats. As the numbers of these manu grow, hopes are that achieving Predator Free Rakiura goals, including eradication of feral cats, will allow them to return.

Guests:

• Victor Tindale, hunter
• Daniel Cocker, Department of Conservation ranger
• Brad Windust, trapper

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

On three small predator-free islands off the coasts of Fiordland and Southland, preparations are underway for what many hope will be the biggest breeding season ever for the kākāpō. Alison Ballance returns to report on New Zealand’s most famous parrot in the Kākāpō Files Season II. She chats to Claire about why this season of the podcast is shaping up to be quite different to the first. Plus, analysts from the Science Media Centre summarise the massive science sector changes that have happened this year, and what is on the horizon for science in 2026.

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

The wetlands and surrounding forests of Te Awarua o Porirua, or Porirua Harbour, were once rich food baskets for Ngāti Toa Rangatira. But decades of development throughout the catchment - large-scale deforestation, road and rail building and urban growth - have brought sediment and pollution into the harbour, damaging the habitat. Veronika Meduna meets some of the team working to restore the harbour to its former plenty.

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Learn more:

• Julian Wilcox recently spoke to artists Jasmine Arthur and Te Rauparaha Horomona about Ngati Toa in Porirua and the opening of a new exhibition Mutumutu ki Mukukai Freshwater to Salt Water.
• Ngāti Toa Rangatira celebrated the return of their sacred maunga, Whitireia, to iwi ownership earlier this year.
• Alison Ballance visited both Porirua and Wairarapa in 2018 to explore how environmental impacts travel from the hills to the sea and what communities are willing to do to make their waterways cleaner and healthier again.

Guests:

• Kaumatua Te Taku Parai, Ashleigh Sagar, Robert McLean and Jaida Howard of Ngāti Toa Rangatira
• Brian Thomas, Porirua City Council
• Bryce and Jacqueline Watkins
• Lisa Casasanto and Jon Bluemel, Kahotea stream Restoration Group
• John McKoy and Simon Glover, Guardians of Pauatahanui Inlet

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

What does a ‘good day’ look like for you? Researchers are using wearable sensors and wellbeing surveys to understand how lifestyle patterns impact life satisfaction. Perhaps this can help us plan for more ‘good days’. Plus, with the help of an EEG study, one neuroscientist graduate considers how social media use might be impacting his brain.

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Learn more:

• Sleep is a fundamental process for us humans, we just don’t function well without enough of it. But what if your job requires long working hours across time zones?
• Exercise is good for our bodies and mental health and, research suggests, can also help our brains maintain and grow nerve cells.
• Recently, a report by the Education Review Office suggested the mobile phone ban in New Zealand schools is working, and that social media should be banned next.
• Australia’s social media ban for those under 16 comes into effect on the 10th of December, while debate continues here as to whether New Zealand should follow.

Guests:

• Professor Scott Duncan, Auckland University of Technology
• Dr Anantha Narayanan, Auckland University of Technology
• Tom Bolus, University of Otago

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

This upcoming summer is likely to be the biggest ever kākāpō breeding season, and RNZ will be following the twists and turns as they happen. The kākāpō files with Alison Ballance return for a second season.

New Kākāpō Files II episodes will appear when news breaks on the Wild Sounds and Kākāpō Files podcast feeds. Don't miss out. Find and follow them now.

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

Our freshwater ecosystems are facing numerous challenges. Many of New Zealand’s lakes have lost much of their native underwater plant life. At the Ruakura ‘tank farm’ in Hamilton, researchers have been working on a project to help restore the freshwater forests.

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Learn more:

• Listen to Invasive: the story of Stewart Smith from the Black Sheep podcast to learn more about New Zealand’s pest fish issue.
• Read more about the koi carp bow hunting that removed tonnes of pest fish.
• While the announcement of the eradication of lagarosiphon from Lake Ngatu was welcome it came on the heels of the disappointing news about finding this invasive weed in two South Island hydro lakes.
• It’s not just invasive plants that are an issue, invasive critters like the gold clam can also cause issues. Contained to the Waikato for the last two years, it has recently been found in a Taranaki lake.
• Restoring freshwater lakes and wetlands is a catchment wide effort, but groups around the motu are working on this.

Guests:

Mary de Winton, Earth Sciences New Zealand

References:

NIWA’s RotoTurf webpage.

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

Oil and water don’t mix — unless surfactants step in. At Auckland University of Technology, a team of chemists has created a new kind of surfactant made from wood pulp rather than fossil fuels or palm oil. They hope that the cosmetic industry will be interested in this greener way to make smooth creams and lotions. Plus, what do geothermal spring microbes have to do with smelly wine?

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Learn more:

• Dr Jack Chen has been on RNZ several times to talk about the chemistry of dishwashing, oven cleaning and laundry detergents.
• Soap is also a surfactant, which is what makes it good at washing oils off our hands, as well as busting open viruses.
• The cosmetic industry is not new, and during the Renaissance there were some ‘interesting’ recipes about, but did they have some good ideas?
• Listen to episodes exploring the use of chemistry in reconstructing past lives, honey fingerprinting, reducing the carbon cost of producing ammonia and creating a perfume to trap invasive spiders.

Guests:

• Dr Jack Chen, Dr Mohinder Naiya, Dr Victor Yim and Josh Van Dongen of Dot Ingredients.
• Sarah Manners, University of Canterbury

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

Until late 2024, nobody had seen te pua o Te Rēinga “the flower of the underworld” in the Wellington region for more than a hundred years. A chance discovery of a small struggling population has kick started a race to protect the plants and help them return.

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Learn more:

1. First Up interviewed Avi Holzapfel about Te Pua o Te Rēinga in 2024
2. In 2020, OCW looked at efforts to resurrect a transplanted population of Te Pua o Te Rēinga at Zealandia.
3. Graeme Atkins is also one of the driving forces behind an effort to help the ngutukākā plant return to the wild, plus the 1769 Garden – a living library of rare local East Coast native plant species.

Guests:

• Graeme Atkins (Ngāti Purou, Rongomawahine)
• Barrett Pistoll – Greater Wellington Regional Council
• Avi Holzapfel – Department of Conservation
• Rhys Mills - Ngā Manu Nature Reserve
• Bart Cox – Wellington City Council

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