KEY POINTS:
New Zealand species are among the world's mammals at risk of extinction, according to a major survey of global wildlife released yesterday.
At least 1141 of the 5487 known mammal species are threatened worldwide, with 188 listed in the highest risk "critically endangered" category.
The "Red List" assessment, issued by the International Union for the Conservation of Nature, said one in three marine mammals were also threatened and the World Wildlife Fund said this was a warning for the survival of New Zealand's marine mammals.
WWF New Zealand's marine programme manager Rebecca Bird said nearly all of New Zealand's native mammals were found at sea.
They include many threatened with extinction, including the blue whale, fin whale, sperm whale and New Zealand sea lion.
The list also includes the hector's dolphin, though the critically endangered maui's dolphin - internationally recognised as the world's rarest marine dolphin - is not listed separately because it is recorded as a North Island subspecies.
The past three decades of fishing with nets had been killing the dolphins faster than they could breed, Ms Bird said.
The hector's dolphin population of about 30,000 in the 1970s had dwindled to just 7270.
The maui's dolphin population situation is even more drastic with research indicating that only 111 individuals remain - a decrease of 93 per cent of its population size since 1970. Researchers for the Red List note that there may currently be as few as 28 breeding maui's females in existence.
"Hector's and maui's dolphins only range within our coastal waters, so their survival depends entirely on how we as a nation choose to respond," said Ms Bird.
Globally the Red List survey, by 1700 experts in 130 countries, has confirmed the devastating impact of forest clearing, hunting, fisheries, pollution and climate change on the populations and ranges of the world's most studied class of animals.
The figures are likely to be a conservative estimate, because scientists have insufficient data on 836 species to even classify how threatened they are.
Ms Bird said nearly half NZ's marine mammals on the Red List were now in the "data deficient" category, including the orca, bryde's whale and dusky dolphin.
IN DANGER
* Of the 4651 species of mammals for which enough data is available, 1139, or one in four, are in danger of extinction.
* At least 76 mammals have become extinct since 1500.
* 188 mammals are in the worst category before extinction, or "critically endangered".
* Twenty-nine of these may already be extinct, such as the baiji or yangtze dolphin in China.
- NZPA
