Many years ago, the wild orangutan's range covered Laos, Vietnam, other areas in Asia and smaller islands in the Indian Ocean. The orangutan is now extinct in these areas and can only be found in the northern areas of Sumatra and on Borneo, Southeast Asia. With a population of approximately 60,000 Bornean orangutans (P.H.V.A. Conference, Jakarta 2004) are not in as immediate danger of extinction as those inhabiting Sumatra, whose population estimates reach only between 4500 and 5400 (Robertson & van Schaik, 2001). The Sumatran orangutan population has decreased by 86% over the past 100 years with a loss of approximately 43% occurring in just the past six years (Robertson & van Schaik, 2001). Assuming this trend continues, coupled with high rates of habitat destruction and food loss, as well as the species' exceedingly slow rate of reproduction, it is estimated that the Sumatran orangutan will become ecologically extinct in the wild within the next ten years (Robertson & van Schaik, 2001). Protection of habitat is vital to the conservation and future well-being of the orangutan.

One of the last strongholds of the Sumatran orangutan is a portion of the Gunung Leuser (GL) National Park located in the province of North Sumatra. The Leuser Ecosystem is the largest protected rainforest system in Southeast Asia and home to one of the largest orangutan populations in the world. However, the range, diversity and orangutan populations of this area continue to be diminished by logging and other human activities.