Approximately 50% of Sumatran orangutan habitat is inside conservation areas directly managed by the Ministry of Forestry, and 78% lies within the boundaries of the vast Leuser Ecosystem Conservation [..]
Sumatran orangutans occur in two main forest habitats, those on dryland mineral soils and those on wet coastal peat. The three main peat areas are Singkil, Kluet and Tripa on the west coast of Aceh [..]
Forests that support Sumatran orangutans also harbour high numbers of other animal and plant species, including some of the most emblematic megafauna species in the world, the Sumatran tiger (Panthera [..]
Between 1985 and 2007, 49.3% of all forests on the island were lost. In the provinces of Aceh and North Sumatra the figures were 22.7% and 43.4%, respectively. Most forest loss has occurred in the [..]
Roads, both existing and planned, are a major threat to Sumatran orangutans as they increasingly fragment populations, making them more vulnerable and less viable. Often such roads are crossing [..]
Oil palm plantations depend on the microclimate conditions generated by nearby forests, and the rivers emanating from orangutan habitat. Not all plantations concessions on the map have been cleared [..]
In the Tripa peat swamps, companies are operating seven large concessions of between 3,000 and 13,000 hectares. They are converting the remaining forests on peatlands into oil palm plantations. The [..]
The main driver for forest loss on peat areas in the Leuser Ecosystem was oil palm development between 1985 and 2007, while for forest on non-peatlands other land uses than oil palm contributed more [..]
Some timber concessions overlap orangutan habitat in a number of key locations. If left to recover after logging, orangutans will gradually return to former concessions. But if the land is converted [..]
The mining industry is a potential threat to Sumatran orangutan habitat in a number of important areas, both directly by its own activities and indirectly by road access. It includes a major gold mine [..]
Only areas with very low human population densities harbour orangutans. In Aceh and North Sumatra, human settlements are still primarily concentrated in the relatively flat coastal zones, particularly [..]
Migration from the island of Nias to the West Batang Toru forests over the last two decades has been largely spontaneous. These settlers have opened up primary forests for agriculture and hunt many [..]
Orangutans are also still regularly killed or captured. This occurs for three main reasons: first, even today some people still hunt orangutans for food, most notably in the non-Muslim parts of North [..]
Most Sumatran orangutan habitat is protected by Indonesian law. The government has created a very comprehensive system of functional forest categories, and institutions responsible for managing its [..]
Under Indonesian law, areas that qualify for protection are based on slope (>40%), sensitive soil types, elevation (above 2000m), and peat land (>3m), thereby preventing any man-made development [..]
