LiveScience.com 28 Aug 08;
A new census in Cambodia reveals remarkably large populations of two monkey species that are threatened with extinction.
The monkey tally, announced today, represents the largest known populations of these species in the world.
Scientists with the Wildlife Conservation Society counted 42,000 black-shanked douc langurs and 2,500 yellow-cheeked crested gibbons in Cambodia's Seima Biodiversity Conservation Area, which is about the size of Yosemite National Park.
The WCS surveys were conducted with the Royal Government of Cambodia's Ministry of Agriculture, Forestry and Fisheries.
The two primate species are found in much lower numbers at other sites in Cambodia and Vietnam. Before the recent discovery, Vietnam was thought to be home to the largest known populations of both species, with 600 black-shanked douc langurs and 200 yellow-cheeked crested gibbons.
Yellow-cheeked gibbons (Nomascus gabriellae) spend their time in the upper canopy of the forest where they eat fruits, leaves and insects. The other Cambodia resident, the black-shanked douc langur (Pygathix nemaeus nigripes) also lives in forests, eating mostly leaves but also some fruits and seeds.
The report comes in the same month as a WCS announcement of the discovery of 125,000 western lowland gorillas in northern Republic of Congo.
WCS scientists attribute the Cambodian boon in the two monkey species to several factors, including successful management of the area and cessation of local logging activities. The conservation area in Cambodia was once a logging area where the two monkey species were extensively poached. Then in 2002, the Minister of Agriculture, Forestry and Fisheries declared the region a conservation area and began working with the Wildlife Conservation Society for management of the site.
Other contributors, the researchers say, include a nation-wide gun confiscation program implemented in the 1990s as well as habitat within the conservation area that provides plenty of primate food.
The report doesn't deliver a completely stellar update.
"Despite this good news in Cambodia, the area still remains at risk from conversion to agro-industrial plantations for crops, including biofuels, and commercial mining," said Tom Clements, lead author of the WCS report.
He added that WCS scientists will continue to work with the Cambodian government to help to ensure the survival of the primate populations there.
The research was supported by the U.S. Fish and Wildlife Service's Great Apes Conservation Fund, MacArthur Foundation, Liz Claiborne Art Ortenberg Foundation, ADB Greater Mekong Subregion Core Environment Program and the Danish Government's Danida program.
New Rare Primate Groups Found in Cambodia
Sara Goudarzi, National Geographic News 3 Sep 08;
Two new populations of rare primate species, both numbering in the thousands, have been discovered in a Cambodia preserve.
A 2008 survey estimates 42,000 black-shanked doucs and 2,500 yellow-cheeked crested gibbons live in Cambodia's Seima Biodiversity Conservation Area.
"These Cambodian animals represent undoubtedly the largest [known] remaining global populations of either species," said lead report author Tom Clements, a researcher at the nonprofit Wildlife Conservation Society (WCS), which led the survey.
Before this survey, the largest known populations of either species were 600 black-shanked doucs and 200 yellow-cheeked crested gibbons in neighboring Vietnam—the only other country where the two species are found. (See a photo of another rare primate group found recently in Vietnam.)
The primates are listed as endangered on the International Union for Conservation of Nature (IUCN)'s Red List of Threatened Species.
They are among the more than 70 percent of Asia's primate species in sharp decline.
Animal Spotters
Sporting long white whiskers, the black-shanked douc lives high in the trees and feasts on leaves and fruit.
Yellow-cheeked crested gibbons are also tree dwellers, eating and sleeping in the upper canopy of evergreen forests.
Between 2005 and 2008, Clements and his team conducted annual surveys in a 300-square-mile (789-square-kilometer) area of Cambodia.
The surveys are the first known attempts to obtain accurate population estimates for the region's native wildlife.
"Although we expected to find a reasonable number of animals, based on the frequency of ad hoc sightings in previous years, we did not anticipate that both primate species would be present in such considerable numbers," Clements said.
Comparisons with other areas suggest that both species are at or near carrying capacity, the maximum number of animals that the habitat can support.
"This suggests that other adjacent areas, which have much lower densities, could support equivalent numbers of animals if successful conservation programs [such as those in Seima] were established," Clements said.
Conservation Success
Hunting and deforestation are among the greatest threats to the newfound primates, experts say.
The survey also highlights the success of establishing conservation programs like the Seima preserve.
"These animals have probably been maintained in Cambodia due to a combination of factors—principally the area's inaccessibility, successful protection of the habitat by the logging concessionaire in the 1990s, and more recently the government-backed conservation program," Clements said.
Patricia Wright is the director of the Institute for the Conservation of Tropical Environments at Stony Brook University in New York State.
She believes the find is an indication of the potential of biodiversity in the region, where resources should be safeguarded.
"This region where [the two species] were found is an unexplored area, filled with forests on steep karst [limestone] mountains," a habitat which these leaf-eating primates specialize in, said Wright, who was not involved with the study.
"There is much work ahead to make sure this habitat and these new populations of these rare primates are protected for the future."
