A German conservation group says it will mount a legal challenge over what it believes are inadequate measures by the New Zealand Government to protect the Maui's dolphin species.
Under new rules announced by Conservation Minister Nick Smith in November a set-net fishing ban will be extended to cover 350 square kilometres of the Taranaki coast, at a distance of between two and seven nautical miles offshore.
But conservationists argue the measure fails to protect the Maui's dolphin, of which only 55 over the age of one are thought to exist.
NABU International said it planned to challenge the decision in the New Zealand High Court and is calling for an international boycott of seafood from New Zealand, the BBC reports.
Its head of conservation Dr Barbara Maas says New Zealand's failure to protect the world's smallest and rarest dolphin is a bitter blow to marine conservation.
She told Morning Report the Government's 350 square kilometre ban is not enough.
"It's like chucking a glass of water at a burning house really, every relevant scientific body in the world have approached the New Zealand government repeatedly saying you need to take the gill nets and the trawl nets out of the Maui's habitat - not range, habitat."
Dr Maas says every area where the dolphin could conceivably be should be protected.
She says the Government has ignored the facts and the advice of the world's scientific community so it can accommodate the commercial interests of its fishing industry.
Dr Maas says it is still possible to avoid the extinction of the Maui's dolphins, because there is still adequate genetic variability in the population, but saving them is a race against time.
NABU has also raised concerns about deep sea mining and the impact on the dolphins of seismic surveying.
Conservation Minister Nick Smith has said the Government will deal specifically with that issue at some point.