Conservationists are criticising the government after it failed to support a move to increase protection of rare Maui's and Hector's dolphins.
New Zealand was one of two dissenting votes against a motion at an international conservation meeting earlier this month seeking more action to prevent the extinction of globally endangered dolphins and porpoises.
At its congress in South Korea, the International Union for Conservation of Nature, while commending New Zealand and other governments for steps taken to preserve rare species, voted to support moves to increase protection.
It wants gillnets and trawl nets banned from the shore to 100 metres of water where both types of dolphins are found and to put observers on every boat using gillnets or trawling in their habitat until the ban is put in place.
The motion, sponsored by the Environment and Conservation Organisations of New Zealand (ECO), was backed by 576 of the union's members.
"There is overwhelming global support for the New Zealand government to take action to stop gillnet and trawl fishing threatening the survival of our endangered dolphins.
"By voting against essential protection for the world's most endangered marine dolphin, the New Zealand government has acted shamefully and can no longer claim to be leaders in conservation," World Wildlife Fund's Rebecca Bird said.
The vote against the motion was also criticised by ECO.
"Almost everyone apart from the New Zealand government wanted to see a strong resolution that recognised the threatened status of these special dolphins and porpoises."
It is estimated that only 55 Maui's dolphins exist off the west coast of the North Island, while there are believed to be around 7000 Hector's dolphins in the South Island.
NZN