The IUCN Red List of Threatened Species 2008

One in four of the world’s mammals is threatened with extinction and half are in decline, the most comprehensive assessment so far has found.

Scientists who carried out the five-year survey of the 5,487 known mammal species described their findings that 1,139 face dying out as “bleak and depressing” and said that it was likely to get worse.

Marine mammals were the worst affected, with more than one in three at risk of annihilation. For the Yangtse river dolphin, it may be too late. It is one of 29 species already declared “probably extinct”.

The survey by the International Union for the Conservation of Nature (IUCN) is the first for 12 years and its findings were announced yesterday at a conference in Barcelona.

Researchers were so concerned about the survival chances of 188 species of mammals that they were described as critically endangered, the highest ranking before extinct.

Among them was the Iberian lynx, which, with an estimated population of 84 to 143 adults left in the wild, is among the rarest animals in the world.

The Tasmanian devil was one of 450 mammals described as endangered, despite previously being regarded as of least concern. It has been afflicted by an infectious facial cancer and its population in Australia has fallen 64 per cent in 11 years.

The survey, carried out by more than 1,700 scientists from 130 countries, is used to draw up the IUCN’s Red List of Threatened Species, the international benchmark for the level of threat to animals and plants.

Of the 44,838 animal and plant species assessed worldwide, 16,928 are under threat, up from 16,306 last year. One in eight birds, one in three amphibians and 70 per cent of plants are threatened.

“Within our lifetime hundreds of species could be lost as a result of our own actions, a frightening sign of what is happening to the ecosystems where they live,” Julia Marton-Lefèvre, the director-general of the IUCN, said. “We must now set clear targets for the future to reverse this trend to ensure that our enduring legacy is not to wipe out many of our closest relatives.”

Jane Smart, head of the IUCN’s species programme, said: “The longer we wait, the more expensive it will be to prevent future extinctions. We now know what species are threatened, what the threats are and where — we have no more excuses to watch from the sidelines.”

Seventy-six species known to be alive in 1500 are now extinct. But while the prospects for some animals are bleak it is possible to save many.

Five per cent of mammals were found to be have stable or expanding populations, including the black-footed ferret, which was on the verge of extinction until conservationists stepped in, and the African elephant, which has been downgraded from vulnerable to extinction to the lower category of near-threatened.

Habitat loss and hunting are regarded as the biggest causes of the decline, with Asian species suffering most among land mammals. They include fishing cats, which have lost much of their territory to agriculture.

The Caspian seal is in severe decline. It was listed as endangered, compared with vulnerable in 1996, after crashing 90 per cent in the past century. Other aquatic species for which there is heightened concern are narwhals and Irrawaddy dolphins.

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