Stolen Apes

BONOBO

CHIMPANZEE

BORNEAN ORANGUTAN

SUMATRAN ORANGUTAN

2010; Kormos et al. 2003; Morgan et al. 2011). Habitat destruc- tion and fragmentation, poaching, respiratory diseases, and other diseases such as the Ebola virus and anthrax are among the primary threats that chimpanzees face. Orangutan The orangutan is the only great ape found in Asia, and histori- cally is thought to have once ranged across Indochina. Today, two distinct species are found on the islands of Borneo and Sumatra, respectively. The Bornean orangutan is divided into three further sub-species. Sumatran orangutan The Sumatran orangutan ( Pongo abelli ) has been listed as Critically Endangered since 2000 and its population has de- creased by 80 per cent over the last 75 years (Wich et al. 2011). This species is native to the Indonesian island of Sumatra and today mainly inhabits the northern end of the island as a re- sult of habitat loss and human encroachment. An estimated 6,600 wild individuals are left, based on nest density surveys and models applied to satellite images of forest distribution (Wich et al. 2008; Mittermeier et al. 2009), although exten-

sive forest clearance and fires in Tripa in 2012 are likely to have reduced the overall number.

Bornean orangutan The Bornean orangutan ( Pongo pygmaeus ) is found on the island of Borneo, in areas governed by Indonesia and Ma- laysia. The species is divided into three sub-species: the Southern Bornean orangutan ( Pongo pygmaeus wurmbii ); the Northeastern Bornean orangutan ( Pongo pygmaeus morio ); and the Western Bornean orangutan ( Pongo pygmaeus pyg- maeus ). The species has been classified as Endangered on the IUCN Red List since 1986 – with an exception in 1996, when it was briefly listed as Vulnerable. As with its Suma- tran relative, the population of Bornean orangutans has de- clined by 50 per cent over the last 60 years, and an estimated 1,950 to 3,100 individuals have been killed annually over the last few decades in Indonesian Borneo, which is higher than the rate at which the species can reproduce (Meijaard et al. 2011). The Bornean orangutan is endemic to Borneo, where it inhabits patchy areas in the central, north eastern and north western part of the island. The latest population estimates indicate a total population of 54,000 remaining in Borneo (Wich et al. 2008).

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