Nearly half of all primate species are threatened with extinction, according to an evaluation by the International Union for the Conservation of Nature (IUCN).
The study — the most comprehensive analysis for more than 10 years and drawing on work by hundreds of scientists — found that the conservation outlook for monkeys, apes and other primates has dramatically worsened. In some regions the thriving bushmeat trade means the animals are being ”eaten to extinction”.
The 2007 IUCN Red List has 39% of primate species and subspecies in the three highest threat categories: vulnerable, endangered and critically endangered. In the revised list 303 of the 634 species and subspecies are in the most-threatened categories. The two biggest threats to primates are habitat destruction through logging and hunting for bushmeat and the illegal wildlife trade.
”We’ve raised concerns for years about primates being in peril, but now we have solid data to show the situation is far more severe than we imagined,” said Dr Russell Mittermeier, chairperson of the union’s primate specialist group and the president of Conservation International.
”Tropical forest destruction has always been the main cause, but now it appears that hunting is just as serious a threat in some areas, even where the habitat is still quite intact. In many places primates are quite literally being eaten to extinction.”
The picture is particularly bleak in South-east Asia. More than 70% of all Asian primates are threatened, while in Vietnam and Cambodia 90% are considered at risk. Populations of gibbons, leaf monkeys and langurs have fallen because of rapid habitat loss and hunting to satisfy the Chinese medicine and pet trade.
”What is happening in South-east Asia is terrifying,” said Dr Jean-Christophe Vie, deputy head of the union’s species programme. ”To have a group of animals under such a high level of threat is unlike anything we have recorded among any other group of species to date.”
In Africa 11 of 13 kinds of red colobus monkey have been listed as critically endangered or endangered. Two — the Bouvier’s red colobus and Miss Waldron’s red colobus – may already be extinct.
Species and subspecies (11% of the total) seen as critically endangered include the mountain gorilla in central Africa, Tonkin snub-nosed monkey in Vietnam and grey-shanked douc langur from Asia.
In the endangered category (22%) are species and subspecies such as the Javan gibbons from Indonesia, the golden lion tamarin from Brazil and Berthe’s mouse lemur from Madagascar. Species are placed in these categories if they have a small population size, are suffering rapid depopulation and have a limited geographic range.
The apparent jump in numbers of threatened primates from 39% to 48% has not happened in the course of one year. The new analysis has filled in missing data that was not available previously, said Michael Hoffman at Conservation International. The last major assessment was carried out in 1996.
”The situation could well have been as bad as this, say, five years ago — we just didn’t know. But now we have a much better indication of the state of the world’s primates and the news is not good,” said Hoffman.
The review, funded by Conservation International, the Margot Marsh Biodiversity Foundation, Disney’s Animal Kingdom and IUCN, is part of an unprecedented examination of the world’s mammals to be released at the IUCN world conservation congress in Barcelona in October.
There was some good news among the bad. In Brazil the black lion tamarin has been brought back from the brink of extinction and has shifted from the critically endangered to endangered category. This is the result of a concerted conservation effort, which has also benefited the golden lion tamarin; it was downlisted to endangered in 2003.
”The work with lion tamarins shows that conserving forest fragments and reforesting to create corridors that connect them is not only vital for primates, but offers the multiple benefits of maintaining healthy ecosystems and water supplies while reducing greenhouse gas emissions that cause climate change,” said Dr Anthony Rylands, deputy chairperson of the union’s primate specialist group.
The scientists also came close to downlisting the mountain gorilla to endangered following population rises in its forest habitat along the borders of Rwanda, Uganda and Democratic Republic of Congo. But political turmoil in the region and an incident in which eight animals were killed in 2007 led to a decision to delay the planned reclassification. —