Almost half the world's primate species are under threat of extinction because they are being eaten or having their homes destroyed by Man.

Monkeys, lemurs, langurs and great apes are among the primates under threat of eradication in a review of all 634 species, apart from human beings.

It was found that 303 of them face the possibility of extinction in the wild, and for 69 species the threat is so severe that they were classified as critically endangered.

Habitat destruction was identified as the single most damaging cause of decline, but for some animals the threat posed by being hunted and eaten by people was the most significant factor.

Among the animals most likely to end up on someone's table are: the Tonkin snub-nosed monkey and Delacour's langur, in Vietnam; the golden monkey and L'Hoest's monkey in Rwanda; and Kirk's red colobus, in Zanzibar and Tanzania.

Asia had the worst record for declining primates, with 71 per cent in the region being under threat. In Cambodia, the country with the worst record, 90 per cent of native species are struggling to survive.

“It's really, really serious,” said Jean-Christophe Vié, of the International Union for Conservation of Nature (IUCN), as the results of the survey were released at the 22nd International Primatological Society Congress in Edinburgh.

“Primates are one of the most threatened groups we've assessed and the threat is growing. Deforestation is the main threat but on top of that we have hunting pressure.”

Primates are among the easiest prey for human hunters because they are comparatively easy to spot in the tree canopy, and often advertise their presence with loud calls.

Red colobuses, langurs, mangabeys, howler and spider monkeys are among hunters' favourites because, at 10 to 20lb each, they make a sizeable meal loaded with protein.

Russell Mittermeier, a primate specialist at the IUCN and president of Conservation International, said: “We have 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. Tropical forest destruction has always been the main cause, but it appears primates are quite literally being eaten to extinction.”

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