A new study has found that the population of western black crested gibbon, a critically endangered primate and a close cousin of humans genetically, may have grown over the last decade in the Ailao Mountains of southwest China's Yunnan Province.

Researchers trekked the mountain, a major habitat for the gibbon, and concluded after two months of recording and monitoring that there are at least 154 groups of gibbons living in the jungle, compared with 124 groups and over 500 individuals that were discovered when the last survey was conducted in 2010 in the same area.

The number of individual gibbons remains unclear so far, as the size of a gibbon group varies from 3-5, according to a ranger named Li Wei who took part in the survey.

The gibbon's frequent calls have become an effective tool for researchers to locate the tree-dwelling animal. Their whistle-like calls serve different purposes which include among others, claiming territory, courting and gathering group members.  

China currently has five remaining wild gibbon species, all under the nation's first-class state protection and classified as critically endangered by the International Union for Conservation of Nature.

Western black crested gibbon, with the largest population among the five, has been deemed as the most hopeful candidate in gibbon's conservation and restoration efforts in China.

(Cover images via video screenshot)

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