This week, an underwater mystery connecting New Zealand and Ireland - the puzzle of the disappearing sponges of Lough Hyne. In the late 1990s/early 2000s James Bell was doing PhD research on the sponge communities that coated the underwater cliffs of this small sea inlet in West Cork. When he returned 15 years later, they had vanished. Why did they disappear, are they starting to recover, and can they be helped to return? Now a Professor at Victoria University of Wellington, these are the key questions that James, and PhD candidates from his lab, have been working to answer.

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In this episode:

00:00 – Divers return, introduction to Lough Hyne and its scientific history.

02:50 – James Bell on his early research at Lough Hyne and the surprising disappearance of sponge communities.

05:15 – Gabi Wood and Kea Witting get ready to dive at Whirlpool Cliffs.

06:30 – James Bell explains the unique tidal regime of Lough Hyne that means it has many diverse habitats.

09:00 – Gabi Wood is collecting water samples to study sponge feeding and nutrient levels.

11:00 – What caused the sponges to disappear.

14:00 – Kea Witting is investigating sponge community recovery.

21:00 – Experiments to help the sponges return…

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