Sumatran orangutans are exclusively found in Indonesia on the island of Sumatra. With only 6,600 individuals left in the wild, the species is in critical danger of extinction.

The only remaining contiguous populations of the Sumatran orangutan (Pongo abelii) that still number over 1,000 individuals all occur within what is known as the Leuser Ecosystem. Covering around 2,500,000 hectares, the Leuser Ecosystem is the largest rainforest ecosystem conservation area in Southeast Asia. Unfortunately, however, in Indonesia today having 'conservation area' status on paper often means little to the various people involved in illegal logging and other destructive practices, legal or otherwise. The Leuser Ecosystem orangutans are by far the most important on Sumatra from a conservation perspective. All three of the largest remaining populations (known as the West Leuser, East Leuser and the Singkil Swamp populations), are struggling to hang on within the Ecosystem's boundaries.

Estimates of remaining orangutan numbers have declined dramatically over the last two decades due to habitat loss. Indonesia was even reported in the Guinness Book of Records for having the fastest rate of deforestation in the world in the last few years. Some surveys concluded that more than 1,000 orangutans were being lost each year due to forest loss during much of the 1990's. According to the most recent survey results published in 2008, only around 6,600 Sumatran orangutans remain in the wild today - compared to slightly over 50,000 Bornean orangutans. Without doubt, with current rates of habitat loss the Sumatran orangutan is under serious immediate threat: scientists have warned that without an immediate halt to the current wholesale destruction of Indonesia's forests, no viable orangutan population will be left in the wild within a decade. This dire situation has led to the Sumatran orangutan being listed as one of the World's Top 25 Most Endangered Primates. Now, more than ever, we must intensify the fight for the survival of this species!