Orangutans are 3e xtant species of the great apes that are classified under the genus Pongo. The orangutans were initially classified as one species. However, they were split into two species in 1996 (Sumatran orangutans and Bornean orangutan). A third species known as Tapanuli orangutan was identified by 2017.
Orangutans are the only existing members of the subfamily Ponginae. They are the most arboreal great apes that spend a considerable percentage of their lives on trees. Wild Orangutans can only be found in two countries on the planet: Malaysia and Indonesia. They are currently living in the rainforests of Sumatra and Borneo.
Natural Habitat of Orangutans
The Sumatran orangutans and Tapanuli orangutans can be found in the northern parts of Sumatra, Indonesia. More than 88% of the orangutans are in the Leuser Ecosystem in Aceh province. The Sumatran orangutans are rarely found in southern parts of River Asahan or south of River Simpang Kanan.
Bornean orangutans are native to Borneo; therefore, they are found in both Malaysia and Indonesia. Sumatra is in Indonesia while Borneo is split between three nations (Indonesia, Brunei, and Malaysia). There are 3 subspecies of Bornean orangutans (Northeast, central, and northwest Bornean orangutans. Northeast Bornean orangutans can be found in Sabah, Indonesia, and East Kalimantan, Indonesia. The central Bornean orangutans live in central Kalimantan and Southern parts of West Kalimantan. The Northwest Bornean orangutans live in northern parts of West Kalimantan and Sarawak (Malaysia).
According to the IUCN, the number of orangutans living in the wild would decrease from 288,000 in 1973 to about 47,000 in 2025. The Bornean population has reduced by 60% in the last six decades. Bornean orangutans have become locally extinct in some parts of Borneo, and the largest surviving population can be found near River Sabangau. The number of Sumatran orangutans reduced by 80% in the last 75 years and currently, they are only found in the northern parts of Sumatra island, particularly in the Leuser Ecosystem.
The orangutan habitat decreased at a very high rate due to forest fires and logging in the early 2000s. Orangutans are hunted and killed for use in traditional medicine, crop protection, and bush meat. Infant orangutans are captured and sold as pets after their mothers have been killed. Another factor that contributed to the reduction of orangutan habitat is the introduction of palm oil plantations in the vast area of the tropical forest. A new species of orangutans known as Pongo tapanuliensis (Tapanuli orangutan) was discovered in 2017 in the Batang-Toru forest in Sumatra. The researchers estimated the population of Tapanuli orangutans to be less than 800, making it the most endangered species of the great apes.
Orangutan Conservation Centers
There are numerous organizations in Malaysia and Indonesia working on rescuing orangutans and then rehabilitating them before releasing them into the wild. The largest organization is the BOS (Borneo-Orangutan-survival) foundation which was established by Willie Smits. The BOS foundation runs various projects in Borneo, including the Nyaru-Menteng rehabilitation center. Other conservation centers in Indonesia include the ones in Bukit Lawang, Gunung-Palung National park, Kutai, Sebangau National Park and Tanjung-Puting National Park among others. The conservation regions in Malaysia include Sepilok Otang-Utan Sanctuary, Matang wildlife center, and Semenggoh wildlife center.