Sumatran orangutan habitat offers excellent opportunities for tourism, including direct viewing of orangutans and other diverse wildlife, jungle treks and caving, rafting and bathing in rivers and hot springs, and even unspoilt sandy beaches where the forest meets the sea.

Opportunity costs for the transition from forest to other land uses between 1994-2009 in Tripa and 1990-2009 in Batang Toru are shown. For the transition to the most profitable land-use a price of slightly more than USD 10 per tCO2 would have been sufficient to offset opportunity costs in Batang Toru. For Tripa this value is lower because of the below ground carbon stocks in the peatlands.

Using satellite images, land use changes were determined at Batang Toru (2001-2009) and Tripa (2001-2009) to calculate overall CO2 emissions. Deforestation in both areas led to different land use transitions, with the predominant land use in Batang Toru after deforestation being disturbed forest and in Tripa, oil palm plantations.

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 to land use changes.

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 species of local wildlife, including orangutans. Currently at least eight Nias communities have been established inside the protected forest in the Batang Toru area, leading to the loss of more than 2,200 ha of orangutan forest habitat in specifically ...

Values for the various non-carbon ecosystem services (water, regulation of floods and landslides, fisheries, prevention and limitation of fires, agriculture, tourism, and non-timber forest products (NTFP) and biodiversity) were calculated with a discount rate of 4% over a 30-year period. Total value for ecosystem services beyond climate regulation being USD 3,735/ha.

Net present value (NPV) is in millions of USD over a 30-year period (2000-2030) at a 4% discount rate. The NPV for local communities under a deforestation scenario would be 3,132 million USD and under a conservation scenario 5,341 million USD. The analysis shows that the local community would benefit most from a scenario under which the forest is conserved, negative effects on ecosystem services are avoided and payments for ecosystem services ar...

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 forests. Some areas remain highly threatened, however, including the Batang Toru Forest (production forest), and the Tripa Swamp Forest (not part of the formal forest estate).

If only the most important orangutan habitat is examined – i.e. forest below 1,000 m – for the 1985-2007 period, the rate of loss was even higher, at 28% and 49% for Aceh and North Sumatra respectively. When only the most species-rich forests (below 500 m) are considered, forest loss between 1985 and 2007 was 36% for Aceh and 61% for North Sumatra. For the carbon-rich peat swamp forests the loss was 33% for Aceh and 78% for North Sumatra.

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 Sumatra. Second, when orangutans enter farms or plantations at the for-est edge, for example to feed on fruit trees or other crops, they are often shot or otherwise killed, and any surviving infant eventually ends up in trade or as someone’s illegal ...

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 lowlands, the very areas where orangutan density is highest.

For a range of land uses that occur in Tripa (forests on peatland) and Batang Toru (forest on non-peatland) the profitability and carbon stocks were determined. Undisturbed forest clearly has the highest carbon stock while rice fields have the lowest.

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 province.

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 to land use changes.

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 concessions cover more than 75 percent of Tripa’s total area of 62,000 hectares. While almost certainly hosting as many as 1,000 orangutans or more in the early 1990s, when still covered in pristine peat swamp forest, there are thought to be less than ...

The globally threatened Lesser White-fronted Goose is a Palearctic migrant, breeding discontinuously in forest- or shrub tundra and mountainous shrubby wetlands from Fennoscandia to easternmost Russia. The species has declined rapidly since the 1950s leading to a fragmentation of its breeding range. Many key stop-over and wintering sites are still unknown. Today, three distinct wild sub-populations remain, of which the two Western Palearc...