female northern yellow cheeked gibbon

Based on population surveys conducted in 2009, there are an estimated 500 groups of northern yellow-cheeked gibbons at the site; each group consists of two adults and their juvenile offspring. 

The gibbon species in Veun Sai-Siem Pang Conservation Area was discovered for the very first time in 2010 in a multinational collaborative effort by primatologists throughout the region with data contributions from Conservation International researchers at the site. 



The (VSSPCA) was extremely important to the discovery of the species and genetic material recovered from the faeces of the wild gibbon group helped demonstrate that this indeed was a new species. 

The discovery of new apes are incredibly rare and the opportunity to see this species in their natural habitat is all the more unique. This new species, Nomascus annamensis, has not yet been assessed for is threat status by the World Conservation Union (IUCN Red List), however it is extremely likely that they will be listed as Endangered. 


mail yellow cheeked gibbonAt the Gibbon site it is possible to see and follow a family group of an adult male, adult female, a sub-adult, a juvenile and an infant. Gibbons are monogamous with groups generally consisting of 2 adults and up to 3 offspring. When the offspring reach maturity at around 7 to 10 years they leave the group to find a mate in another part of the forest to raise their own offspring. Gibbons are fiercely territorial of their areas of the forest and make their claims known through ritualistic vocalizations. 


The gibbons live in perfect harmony with the Kavet people who consider the gibbons as extremely important; they are not hunted but respected and share the jungle together.  


This in huge contrast with many other areas in Southeast Asia, where gibbons and other primates are persecuted and hunted for bushmeat, for their perceived medicinal properties, or for the trade in pets.  This is why such a healthy population exists in this area and is a testament to the importance of the site and its relatively untouched nature. We hope that showing that gibbons and the natural environment can be valuable maintained as they are will help preserve this species and this area for generations to come. 


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