Survey doubles the number of world’s rarest ape

Female gibbon. Zhao Chao/FFI

Prior to the survey, it was thought that only about 50 gibbons were left alive, but it is now estimated that some 110 inhabit the forests along the borderbetween China & Vietnam. The survey was the result of an unprecedented cross-border collaboration between Vietnam and China, and its findings will enhance the effectiveness of conservation efforts to protect this Critically Endangered species.

First detailed photos
The study also captured the first detailed photos of the species in the wild as well as video footage. In early September 2007, survey teams of biologists, government rangers and local villagers led by FFI surveyed forest on both sides of the China-Vietnam border for cao vit gibbon groups, counting them either by sight or

by recording their evocative songs. Preliminary estimates suggest that as many as 20 family groups survive. In addition, gibbons are now being reported from parts of the forest they had not previously been recorded in. People from Lung Hoai Village in Vietnam told project staff that they are now hearing gibbon songs near their village where they didn't before.

Rediscovered after 40 years
FFI has been working to save the cao vit gibbon (a sub-species of the eastern black crested gibbon, scientific name Nomascus nasutus nasutus) since it was rediscovered after 40 years with no sightings by FFI staff members who found a small remnant sub-population in Cao Bang Province, Vietnam in 2002. FFI began conservation efforts despite the scarcity of data on the species. Four years later, three more family groups were discovered across the border in Guangxi Autonomous Region, China, where they were believed to be extinct.

Male gibbon. Credit Xu Yongbin/FFI

"We didn't want the cao vit gibbon to go the way of the Yangtze River dolphin, which was declared extinct last year."

FFI has established community groups to patrol and protect the gibbon's forest habitat and is working with local people to prevent habitat loss caused by livestock overgrazing, firewood collection and encroaching agriculture. Simple and cost effective measures such as providing villagers with simple fuel-efficient stoves are helping to relieve pressure on the gibbon's habitat.

The survey demonstrates the success so far of efforts to protect the gibbon. FFI was able to carry out the survey due to the successful training and participation of local people and the support of local government partners. We have made steady progress on the conservation of the species; in 2007, we helped to establish the Cao Vit Gibbon Conservation Area in Vietnam, and a nature reserve is currently being planned in China.

To hear gibbon song recordings and watch a video of their amazing forest acrobatics, visit www.fauna-flora.org.

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