Our Changing World

Since 2018 there's been a massive effort underway to clear over 110,000 hectares of South Westland of possums, rats and stoats. As the pest numbers have dropped the native flora and fauna seem to have flourished. The eradication stage is now nearing completion, and the focus is switching to maintenance. What will it take to keep the pests out long-term? And what can be learned from this large-scale project that could be used elsewhere in Aotearoa?
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Read/Listen to the rest of the reports from Tess Brunton’s reporting trip to the West Coast, about the eradication project, the work of species dogs, the feedback from tour operators and how rowi, New Zealand’s rarest kiwi, has been helped come back from the brink.
For more on the use of AI in pest management project, listen to how the Southern Lakes Sanctuary team have been making use of it at Wye Creek.
Guests:
Chad Cottle, Predator Free South Westland
Ethan Perry, Predator Free South Westland
Nate St Hill, Predator Free South Westland
Pouri Rakete-Stones, Predator Free South Westland
Dion Arnold, White Heron Sanctuary Tours
Go to this episode on rnz.co.nz for more details

Some insects communicate using a secret language that we can’t sense – a language of vibrations. Now researchers at the Bioeconomy Science Institute are starting to decode what insects are saying to each other. They hope to harness this knowledge to develop new, chemical-free methods of pest control to help farmers and growers.
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Insects can also be recruited to help. For example, insects can be released into New Zealand for biocontrol in the effort to combat invasive weeds.
While we often talk about the impact of invasive mammals on New Zealand’s bird life, they are also a problem for native insects too.
We’ve got some invasive pest spiders here too, but researchers are trying to figure out if they can trap them by developing a special spider perfume.
Guests:
Dr Mark MacDougall, Bioeconomy Science Institute
Dr Lloyd Stringer, Bioeconomy Science Institute
Pete Mundy, Castle Rock Orchards
Dr Rachael Horner, Bioeconomy Science Institute
Dr Bethan Shaw, Bioeconomy Science Institute
Go to this episode on rnz.co.nz for more details

When do humans begin to interact with the world, and develop our sense of self? When we are born? Or might it start even earlier than that? Our visual systems are a key way that we perceive the world. New findings from the University of Waikato have shown that light can enter the womb and that we might already be learning about the world before we arrive in it.
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Listen to Our musical minds to learn why, to psychologists, humans’ musical ability is just weird.
Like our sense of vision, our ability to hear also involves physical inputs from the world around us combined with the processing and prior knowledge of our brains. But sometimes things can go a bit awry, such as happens for those with tinnitus.
Our visual system is evolved for daylight, but what about those creatures that live in the deep darkness, such as squid.
Professor Vincent Reid’s early research in this area was covered by RNZ podcast ‘This Way Up’ in 2017.
Hear more from William Ray in the award-winning Black Sheep podcast series, or in a recent Our Changing World episode about the Flowers of the Underworld.
Guests:
Professor Vincent Reid, University of Waikato
Associate Professor Jacob Heerikhuisen, University of Waikato
William Ray, Janella Espinas, James Espinas Ray
Go to this episode on rnz.co.nz for more details

A Southland company is growing red seaweed as a supplement that’s been shown to significantly reduce methane emissions in beef and dairy cattle. In our last summer science series episode, Cosmo Kentish-Barnes of the Country Life team heads to Bluff to learn more.
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You can read Cosmo Kentish-Barnes' story about this topic, Red seaweed cuts methane emissions from cattle, scientists say.
Cosmo signed off from the Country Life team earlier this year, after 17 years as the show's South Island producer. You can listen to his final episode.
There are also pāua and whitebait farms operating out of the Ocean Beach Aquaculture Hub in Bluff. Kate Evans visited both ventures in a 2024 episode of Voice of Tangaroa, Fish out of water.
Guest:
Brent Jackson, production scientist
Go to this episode on rnz.co.nz for more details

Why do we spend more than we need to? Is it mood, FOMO, the desire to impress? Or maybe some tricky behavioural triggers we're not even aware of? Our summer science series continues with an episode of the RNZ podcast Thrift, in which Katy Gosset gets to the heart of the matter with a consumer behaviourist, and shares some tips to stop us spending.
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You can read about the psychology of spending in RNZ's story: Why do we spend more than we need to?
Thrift is an upbeat podcast that offers wise ways to beat the cost of living crisis and get the best from your money. Listen to more episodes of Thrift.
Guest:
Ekant Veer, consumer behaviourist
Go to this episode on rnz.co.nz for more details