Snapper catch brings questions

A rare catch of snapper at Dunedin’s new Boiler Point fishing jetty is raising big questions about the effect of climate change on fish distribution patterns.

Youngsters Sienna and Liam Dalley, of Townsville, Australia, were fishing at the jetty near Careys Bay about a fortnight ago when they caught a snapper.

Their grandfather, Associate Prof Hamish Wilson, of the University of Otago general practice and rural health department, took a photo of his visiting grandchildren and the fish and submitted it to the Otago Daily Times.

Prof Wilson, who has previously fished for snapper in the Marlborough Sounds and the North Island, said it was "fantastically unusual" to hear of them being caught in Otago Harbour and agreed they were a relatively warm water fish traditionally not caught south of the Marlborough Sounds.

Prof Steve Wing, of the Otago marine science department, told the ODT in January last year that climate change was likely a main reason why kingfish were being quite commonly found in waters off the Otago coast.

Prof Wing, a marine ecologist, said kingfish on the Otago coast had become "sentinels of climate change".

Prof Wilson said yesterday something had changed in respect of snapper, but because of his lack of scientific expertise on fish, he could not comment on whether climate change had contributed.

Prof Liz Slooten, of the Otago zoology department, said she was not a fish specialist, but Fisheries New Zealand and the country’s Fishing Industry Board had acknowledged significant changes in distribution of fish species, partly due to climate change.

Prof Slooten could not say the "extremely unusual" Dunedin snapper find had resulted from climate change.

Nevertheless, changes had clearly been happening and climate change was a likely overall explanation, she said.

She is a specialist in New Zealand’s endangered Hector’s dolphins and "critically endangered" Maui’s dolphins, and said it was too soon to estimate what effects changes in available food sources would make to the dolphins, which were found only in New Zealand waters.

john.gibb@odt.co.nz