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 Рand 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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