Orang-utans spend most of their time in the treetops of the rainforests - in fact the name orang-utan means "person of the forest". They pass from tree to tree by climbing or swinging. Their strong arms stretch out longer than their bodies (up to 2.1m across) and allow them to move about in the rainforest canopy with ease, or to hang from branches eating fruit and leaves. When climbing, orang-utans use all four limbs - their big toes are opposable (like a human's thumbs) so they can grip branches with their feet as well as their hands. On the ground, orang-utans can stand upright, but they walk on all fours.

They are active during the day, and at night the females and young males sleep in nests which they build in the trees each evening. Due to their heaviness, mature males often sleep on the forest floor.

Orang-utans usually live on their own. This is particularly the case with adult males, who only associate with others during mating, which happens throughout the year. Female orang-utans typically give birth to one baby, although twins are not unheard of. Mothers take great care of their young, who remain with them for up to six years. The average lifespan for an orang-utan is 30 years, and maturity is reached at seven to 10 years of age.


Current threats & problems

Because orang-utans spend most of their lives alone in the trees, calculating population numbers is an extremely difficult task. However, evidence such as numbers of nests suggests that fewer than 30,000 orang-utans exist in the world today. Of these, the vast majority are found in Borneo (about 24,000), with just a tiny population surviving in Sumatra. Over the past 100 years orang-utans have lost 91 per cent of their population.

The most serious threat to orang-utans is the destruction of their rainforest habitat. In the last 20 years an estimated 80 per cent of suitable orang-utan habitat has disappeared, and only around two per cent of what remains is legally protected. The main causes of this habitat loss are commercial logging, clearance for agriculture, and conversion to plantations. Not only does commercial logging destroy the forest, it is often done illegally, creating roads into previously inaccessible areas, which provides access to poachers

Fires pose an increasingly serious threat to the orang-utan's habitat - WWF's Indonesia Programme estimates that in 1997 around 10 million hectares of land were burned in Indonesia. When areas of forest are destroyed, the orang-utans lose both their home and source of food (fruit and leaves).

Despite legal protection in Sumatra and Borneo, orang-utans are often killed for their meat - their slow movements make them easy targets. More serious is the trade in body parts, particularly skulls, which continues despite the efforts of the authorities to stop it. The market in orang-utans for pets thrives in many Asian countries, particularly Taiwan, where the population of orang-utans per square kilometre in the capital, Taipei, has been estimated to be greater than in their natural habitat.

Because orang-utans reproduce slowly, any loss of life is very serious - the population takes many years to recover. Statistics show that a one per cent increase in the death rate could bring about their extinction within three decades.


What WWF is doing

WWF has been involved in orang-utan conservation since 1962. Research has played a vital part in the work carried out over the past three decades, with surveys being conducted in many parts of Indonesia and Malaysia. Data collected has been used to show where there is a particular threat to orang-utans and their habitat.

As a result of this continuing work, WWF has been able to help governments and other conservation organisations in creating and extending protected areas and wildlife sanctuaries where hunting and logging are banned.

WWF has also helped governments to enforce restrictions on the trade in live animals and orang-utan products. When live orang-utans are rescued from traders, they are often taken to refuges where they can recover and be rehabilitated, and eventually be released back into the wild. Wherever WWF works in the field, great importance is placed upon the extensive knowledge and expertise possessed by local people and communities.

With your support, WWF will continue its work to protect the orang-utan and its essential forest habitat.