Kākahi are a keystone species in lake and river ecosystems, keeping the water clean by filtering one litre of water every hour. These native mussels once blanketed lakebeds across Auckland – but recent surveys found an alarming decline and disappearance across many lakes. A team of scientists and divers have mounted a rescue mission for one of the last remaining kākahi populations, trying to keep the mussels safe from invasive fish through all the steps of their complicated – and fascinating – life cycle.

Guests:

• Madison Jones, Senior Healthy Waters Specialist, Auckland Council
• Belinda Studholme, Senior Biosecurity Advisor – Freshwater, Auckland Council
• Ebi Hussain, Submerged Environmental and Aotearoa Lakes
• Andrew Simpson, Global Dive

Learn more:

• Read the article that accompanies this episode: A rescue mission saving rare freshwater mussels.
• Meet the bullies – the native freshwater fish that host the kākahi in their parasitic stage – in this 2023 episode recorded by Claire at Zealandia, where the fish have been translocated.
• Alison Ballance covered the translocation of kākahi into Zealandia back in 2018.
• Wondering how the perch and other pests ended up in Lake Rototoa? Black Sheep has the details in the episode Invasive: the story of Stewart Smith.

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