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

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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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• 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

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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.

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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.

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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

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An invasive species has taken hold in the Waikato River, and it’s multiplying fast. Gold clams, tiny but relentless, are now found along a large stretch of the awa, where they threaten water infrastructure, and native species. Where might it invade next, and can we control it?

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Learn more:

• Among their other conservation activities, the team at Kids Greening Taupō have taken on the challenge of speaking to every class about the gold clam to raise awareness.
• MPI’s John Walsh spoke to Paddy Gower on Nine to Noon after last year’s gold clam survey, and more recently to Kathryn Ryan about following the rules to prevent the clam’s spread this trout fishing season.
• In Auckland, efforts are underway to protect the native kākahi from the threats of introduced fish.

Guests:

• Dr Michele Melchior, Earth Sciences New Zealand
• Karl Safi, Earth Sciences New Zealand

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New Zealand’s marine search and rescue region stretches from Antarctica to north of Samoa. If someone goes missing without any means of communication, that’s a lot of ocean to search. Now researchers and the New Zealand Defence Force have teamed up to develop and test a low-tech, no-battery device that can be picked up by radar – including that beamed down by satellites orbiting Earth.

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In this episode:

01:30 At Mission Bay Beach Dr Tom Dowling demonstrates the device

03:40 In the University of Auckland’s Space Institute lab the team explain the device design, and how it works.

10:00 Dr Tom Dowling talks about the radar reflector trials in Campbell Island and Omaha beach

13:00 Dr David Galligan, director of Defence Science and Technology on why DST is interested in the device

19:00 The satellites are the second side of the equation. Dr Tom Dowling explains how that works.

20:50 Back at Mission Bay Beach Dr Tom Dowling explains how the radar reflector would be an additional part of a kit on a boat and how it would work to narrow down the search area…

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