Conservationists and opposition politicians have stepped up calls for the New Zealand government to take urgent measures to protect the country's endangered native dolphins after one of the animals was found dead last week.
The Department of Conservation (DOC) announced Monday that it had yet to identify the animal as either a Hector's dolphin or the more endangered Maui's dolphin, which is thought to have just 55 of its kind.
A preliminary pathology report said the animal, found on a beach on the west coast of the North Island, had died of natural causes and not as a result of "human interaction" such as injury from fishing nets, said a DOC statement.
DNA tests to determine whether it was a Hector's or Maui's dolphin would take at least two weeks, it said.
Conservation spokesman for the main opposition Labour Party, Grant Robertson, said Monday that emotions were running high as the death could mean just 54 Maui's dolphins were still alive.
"The government and fisheries sector can't continue to prevaricate. It's too important -- we are talking about the impending extinction of an entire species," said Robertson in a statement.
Extensions to set net bans on the country's West Coast and a marine mammal sanctuary, expected to come into force next month, could not guarantee the dolphins' survival, he said.
The opposition Green Party on Sunday called on the government to implement an immediate moratorium on set-net fishing on the west coast of the North Island.
Regardless of how the dolphin died, the government should take all practicable steps to ensure the dolphins' survival, said Green Party oceans spokesperson Gareth Hughes in a statement.
Earlier this month, an international coalition of conservation campaigners called on the government to immediately place restrictions of fishing nets, in a letter to Prime Minister John Key.
The world's smallest dolphin, the Maui's dolphin, is the most endangered of all whales and dolphins, and lives only in New Zealand waters.
Hector's and Maui's dolphins are primarily threatened by lethal by-catch in trawl and gill nets, but other factors, including habitat degradation, are also dangers, say conservationists.
Last month, the government announced it was considering further measures to protect the Maui's dolphin after the Department of Conservation warned the existing population was likely to diminish.
Primary Industries Minister David Carter and Conservation Minister Kate Wilkinson announced they were proposing added protection measures while a full review was carried out.