RNZ Insight: A line in the Sand for Freshwater Quality? Kate Gudsell

Gerry Closs heads the University of Otago's Zoology Department

Professor Gerry Closs specialises in freshwater fish – and he says their populations are suffering. Photo: RNZ/Kate Gudsell

He said losing biodiversity made it more difficult for streams to process pollution, and a new pattern of decline was starting to emerge.

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