Extinction Closes in on Half the World's Apes, Monkeys

"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 Russell Mittermeier, longtime chairman of the IUCN Species Survival Commission's Primate Specialist Group and the president of Conservation International.

Habitat destruction, through the burning and clearing of tropical forests, which also emits at least 20 percent of global greenhouse gases, is a major threat to primates. Other threats include the hunting of primates for food and the illegal wildlife trade.

Indochinese Lutung, Trachypithecus germaini, Endangered, Phnom Tamao Zoological Garden and Wildlife Rescue Center, Cambodia. (Photo © CI/Russell A. Mittermeier)

"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," Mittermeier said.

The first comprehensive review in five years of primate conservation status presented at the conference shows that of the 634 kinds of primates in the world, almost half are in danger of going extinct, according to the criteria of the Red List of Threatened Species compiled by the IUCN, formally known as the International Union for the Conservation of Nature.

With the input of hundreds of experts worldwide, the primate review provides scientific data to show the severe threats facing these animals, which share virtually all DNA with humans.

All great apes - all gorillas, all chimpanzees, all orangutans, all bonobos - are either Endangered or Critically Endangered.

In Asia, more than 70 percent of primates are classified on the IUCN Red List as Vulnerable, Endangered or Critically Endangered - meaning they could disappear forever in the near future.

In both Vietnam and Cambodia, 90 percent of primate species are considered at risk of extinction. Populations of gibbons, leaf monkeys, langurs and other species have dwindled due to habitat loss worsened by hunting for food and to supply the wildlife trade in traditional Chinese medicine and pets.

"What is happening in Southeast Asia is terrifying," said Jean-Christophe Vié, deputy head of the IUCN Species Programme. "To have a group of animals under such a high level of threat is, quite frankly, unlike anything we have recorded among any other group of species to date."

Kirk's Red Colobus, Procolobus kirkii, Endangered, Zanzibar, Tanzania (Photo © Tom Struhsaker)

Elsewhere, the survival of species from tiny mouse lemurs to massive mountain gorillas is in jeopardy, the report shows.

In Africa, 11 of the 13 kinds of red colobus monkeys assessed were listed as Critically Endangered or Endangered. Two may already be extinct: Bouvier's red colobus, Procolobus pennantiibouvieri, has not been seen in 25 years, and no living Miss Waldron's red colobus, Procolobus badius waldroni, has been seen by a primatologist since 1978, despite occasional reports that some still survive.

"Among the African species, the great apes such as gorillas and bonobos have always tended to grab the limelight, and even though they are deeply threatened, it is smaller primates such as the red colobus that could die out first," said Richard Wrangham, president of the International Primatological Society.

Non-human primates are important to the health of their surrounding ecosystems, the report points out. Through the dispersal of seeds and other interactions with their environments, primates help support plant and animal life in tropical forests. Healthy forests provide vital resources for local human populations, and also absorb and store carbon dioxide that causes climate change.

Meanwhile, scientists continue to learn more about primates and their role in the world.

Since 2000, 53 species of primates previously unknown to science have been described - 40 from Madagascar, two from Africa, three from Asia and eight from Central and South America.

Golden lion tamarin, Leontopithecus rosalia, Endangered, Atlantic forest, Brazil (Photo © CI/Russell A. Mittermeier)

In 2007, researchers found a long-rumored population of Critically Endangered greater bamboo lemurs, Prolemur simus, in Madagascar in a wetland 400 kilometers (240 miles) from the only other known home of the species. In total, this species numbers about 140 individuals in the wild.

Despite the grim assessment, conservationists point to one success in helping targeted species recover.

In 2003, two Brazilian primates - the black lion tamarin and the golden lion tamarin were downlisted to Endangered from Critically Endangered as a result of three decades of conservation efforts involving many institutions.

Populations of both animals are now well-protected but remain small, and conservationists say there is an urgent need for reforestation to provide new habitat for their long-term survival.

"If you have forests, you can save primates," said Anthony Rylands, the deputy chair of the IUCN Primate Specialist Group.

"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," Rylands said.

The bodies of four of the eight mountain gorillas killed in July 2007 in Virunga National Park, a World Heritage Site. (Photo courtesy International Gorilla Conservation Program)

But the slayings of eight mountain gorillas in 2007 and continuing political turmoil in the region delayed the planned reclassification.

"The great apes are more diverse – and more threatened – than many of us ever expected," the scientists say on the IUCN SSG Primate Specialist Group website. At least 14 kinds of great ape are now recognized - five kinds of gorillas, four of chimpanzees and the singular bonobo, all found in central and western Africa, plus four kinds of orangutans known from tropical Asia.

In total, the gorillas, bonobo and chimpanzees occur in 21 African nations. Of the orangutans, one species is wedged into northernmost Sumatra, and the other, divided into three subspecies, survives on the island of Borneo.

The primate species review, funded by Conservation International, the Margot Marsh Biodiversity Foundation, Disney's Animal Kingdom and the IUCN, is part of an unprecedented examination of the state of the worlds mammals to be released at the IUCN World Conservation Congress in Barcelona in October.

The IUCN Red List sets a series of criteria for a species to be categorized as threatened. In cases where scientists lack the necessary information, the species can be listed as Data Deficient. This classification applied to nearly 15 percent of the primates in the new review. The scientists said that many of those species, particularly newly discovered ones, are expected to eventually be classified as threatened.

For a list of the assessments of all primate species and subspecies as they will appear on the 2008 IUCN Red List of Threatened Species in October, visit the website of the IUCN SSC Primate Specialist Group at: www.primate-sg.org

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