Kloss’s Gibbon Hylobates klossii
Endangered
Mentawai Islands, Indonesia
The Kloss’s Gibbon belongs to the genus Hylobates. The word Hylobates means ‘Forest Walker’ in Greek. The gibbons in this genus are known for the white circle of fur around their faces. They are known to communicate in species-specific song when defining territory or attracting mates. They sing in regional accents to each other, have long swinging arms, inquisitive natures and superior acrobatic skills, they spend most of their lives high up in the tree-tops.
The Kloss’s Gibbon is arboreal, diurnal, and omnivorous, though predominantly frugivorous (Whitten 1982a). Although disturbance levels in this species’ habitat are variable on different islands, a recent survey detected similar population densities in un-logged forests, forests logged 10 years ago, and those logged 20 years ago (Paciulli 2004, Whittaker 2005).
This species is threatened mainly by hunting and commercial logging (Whittaker 2006). It is also threatened by conversion to oil palm plantations, in addition to forest clearing and product extraction by local people (Whittaker 2006).
IUCN Red List
The Kloss’s Gibbons live in #Mentawi #Malaysia endangered on @IUCNredlist by #palmoil #deforestation. Join the #Boycott4Wildlife on the supermarket brands responsible for rainforest destruction. See more on my website
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The Kloss’s Gibbon is Endangered due to a past and continued population reduction, estimated at more than 50% over a period of 45 years, including two past generations (1986-2015) and the current generation (2016-2030). The population reduction is due to widespread local hunting for cultural reasons and loss of habitat, particularly in North Pagai, South Pagai and Sipora Islands.
A recent study shows that habitat loss in the Mentawai islands was mainly due to forest conversion for agriculture expansion by local communities. A total of 73,500 ha of forest in Siberut, North Pagai, South Pagai and Sipora Islands have been allocated for oil palm plantation by the local government and about 34,000 ha (46%) was granted to only two companies (FFI, unpublished report)
Further Information

Liswanto, D., Whittaker, D., Geissmann, T. & Whitten, T. 2020. Hylobates klossii. The IUCN Red List of Threatened Species 2020: e.T10547A17967475. https://dx.doi.org/10.2305/IUCN.UK.2020-2.RLTS.T10547A17967475.en. Downloaded on 06 February 2021.
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