Orangutan

Asian relatives
The orangutan (say oh-RANG-oo-tan) is the only species of great ape that lives in Asia. They are the largest tree-living mammals. They are close relatives to humans.

Habitat
Orangutans are found in the oldest rainforests in the world, on the islands of Borneo and Sumatra. They were once found over much of China and Southeast Asia, but are now only found on these two islands. 

Physical features
Orangutans are covered with long reddish hair. Their long arms are ideal for swinging from branch to branch. Adult males weigh about 144 kg, females, about 65 kg.

Adult males have large cheek flaps on their faces and a sac under their chins which they inflate with air to make a long call which can be heard a kilometre away.

Behaviour 
Males are generally solitary, females are accompanied by their young. Orangutans rarely come to the forest floor, spending their time mostly in the upper canopy of the trees. They build a fresh nest each night, high up in the trees. Much of their time is spent eating. The young are dependent on their mothers for about eight years. Only human young are dependent for a longer period of time.

Food 
Orangutans eat mainly fruit, their preferred food being wild figs and durians. About 400 separate items have been identified as part of their diet, including roots, nuts and berries, insects, reptiles, eggs, bark and leaves.

Conservation status
Orangutans are classified as 'vulnerable'. There are approximately 4000 living in national parks on Sumatra and Borneo.

However, some scientists think that the orangutans of the two islands may actually be different species of orangutan. That would mean that both species would be reclassified as 'critically endangered'.

Reasons for low numbers of orangutans
Habitat destruction due to logging
The demand for rainforest timber means that the forests are logged faster than they can grow. Some rainforest trees take 60 years to reach maturity and 200 years to reach full height.
Poachers
Baby orangutans are very cute and people want them as pets. Poachers steal babies, often killing the mother in the process, and sell them. However, they grow into very large, strong animals and are dumped. Often the animals are suffering from disease because they have been fed unsuitable food, or they may be injured from poor treatment.There are rescue centres which try to train orangutans to be independent and eventually reintroduce them to the wild in protected areas. This is a slow process and orangutan numbers continue to decline.

If you use any of this information in your own work, acknowledge this source in your bibliography like this:
A Trip to Indonesia (2001). [Online], Available: www.kidcyber.com.au

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Updated 27 January 2001