The suicidal pace of deforestation and peatlands destruction in just the past 10 years has created pockets of isolated populations across Borneo and Sumatra. Habitat losses with the destruction of vast areas of tropical forest throughout the island and their conversion to agriculture (mostly oil palm plantations – Elaeis guineensis, but also acacia, rice, subsistence crops, cocoa, etc). An overall loss of 15.5 million hectares of forest (24% of total forest area) was recorded between 1985 and 1997 in Sumatra and Kalimantan, while 37% of the total forest area was lost in Sabah between 1950 and 2000 (FAO 2000). In the lowlands (prime orangutan habitat) this figure is higher and reaches more than 60%. We consider that today only 86,000 km² of habitat remains available to the species throughout the island (which is about 740,000 km²). Protected areas home to significant orangutan populations are also threatened by habitat loss.
The rapid expansion of oil palm plantations in Borneo in response to international demand (the oil is used for cooking, cosmetics, mechanics, and more recently as source of bio-diesel) has accelerated habitat losses. Between 1984 and 2003, the area planted with palm oil on Borneo increased from 2,000 km² to 27,000 km²: about 10,000 km² is located in Kalimantan; 12,000 km² in Sabah and 5,000 km² in Sarawak. Many areas used to be prime habitat for the orangutans: eastern lowlands of Sabah, the plains between the Sampit and Seruyan rivers in central Kalimantan, etc.