The International Whaling Commission wants urgent action to prevent New Zealand's Maui's dolphins from becoming extinct.
A report by the Commission's scientific committee said the rare dolphins, along with Mexico's vaquita porpoise, were threatened by the accidental by catch in gillnet fisheries.
The committee expressed "extreme concern" and called for a ban on gillnet fishing to allow for a safe corridor for Maui's dolphins between the North and South Islands.
There are believed to be about 55 Maui's dolphins remaining.
WWF spokeswoman Aimme Leslie said fishing could drive the dolphins to extinction.
"Advances in technology mean that fishermen and Maui's dolphins can safely share New Zealand's waters."
Alternative fishing techniques should be used and all gillnets and trawl nets must be kept out of Maui's habitat, she said.
Austria's representative at the meeting Michael Stachowitsch said it was time for diplomatic niceties to take a back seat and immediate action be taken.
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