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Conservation Of Orang-utans

For thousands of years, the orang-utan has been exploited by humans. Early humans found it an abundant source of food and hunted it to local extirpation in many areas. More recently in Borneo, it has served as a substitute for humans in traditional head-hunting rites. In the 1960s, the population of orang-utans was decreased by the collection of young animals for sale to zoos and the pet trade. Despite legal protection by the governments of Malaysia and Indonesia, the capture of young orangutans has not yet been completely halted. There are now an estimated 12,000-21,000 wild orang-utans in Borneo, and 9,000 on Sumatra.

Today the greatest threat to this species is the destruction and disturbance of their habitat. Old-growth tropical rainforest is rapidly being logged and cleared for agricultural development on Borneo, leaving only patches of suitable habitat. In recent decades, wildfires have also destroyed extensive areas of forest habitat. This has happened during years of unusual drought associated with El Niño events, when fires lit by people to develop agricultural land accidentally escape into the wild forest.

The orang-utan is extremely sensitive to human intrusions, and as a consequence suffers reductions of an already low rate of reproduction when frequently disturbed. For this reason, research on how it responds to alteration of its habitat, especially selective logging, is necessary. Several protected reserves for this species have been designated in Sumatra and Borneo, but these reserves must be managed effectively and additional habitat must be preserved if the orang-utan is to escape extinction.

See also Apes; Primates.



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Betsy A. Leonard


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—Living in trees.


—To swing by the arms from branch to branch.


—Having two distinct forms.


—The tree and fruit of Durio zibethinus, a plant cultivated in Southeast Asia. The fruit is 6-8 in (15-20 cm) in diameter and has a hard external husk covered with coarse spines. Inside, five oval compartments are filled with sweet, custard-like pulp.


—A protruding rim, edge, rib, or collar.


—The reproductive organs, especially the external sex organs.


—The period of carrying developing offspring in the uterus after conception; pregnancy.


—Adapted for seizing or holding, especially by wrapping around an object.


—Having thick, fleshy leaves or stems that conserve moisture.

Additional topics

Science EncyclopediaScience & Philosophy: Octadecanoate to OvenbirdsOrang-utan - Physical Characteristics And Habits, Diet, Communication, Behavior And Reproduction, Conservation Of Orang-utans