Most Endangered Apes

Scientists list these four apes - a gorilla from Africa, an orangutan from Indonesia and two gibbons from Asia - among the 25 most endangered primates in the world.

Cross River Gorilla

Cameroon, Nigeria Gorilla gorilla diehli

Somewhere between 200 and 300 Cross River gorillas remain in forests near the border between Cameroon and Nigeria. This great ape subspecies began a sharp decline 200 years ago when hunters acquired guns. Some bushmeat hunting still continues, endangering the group's survival. Rapid cutting of the remaining forest for agriculture also poses a major threat.

Sumatran Orangutan

Indonesia Pongo abelii

This orangutan species is native only to Sumatra, where about 7,000 individuals are left, all near the island's north end. Over 10% of the lowland forests that the tree-dwelling apes require is logged each year and much of the land converted to agriculture. The pace of clearing and road-building is not slowing down. At this rate of habitat loss, the world's population of Sumatran orangutans could be halved in a decade.

Western Hoolock Gibbon

Bangladesh, India, Myanmar Hoolock hoolock

The population of this south Asian gibbon has declined by over 90% since the early 1970s when they totalled over 100,000. Today less than 5,000 survive. In the last five years, western hoolock gibbons disappeared from 18 locations. Numbers are precariously low, fewer than ten individuals, at half of the 122 sites in Bangladesh and India where they still live.

Hainan Black-crested Gibbon

China (Hainan Island) Nomascus hainanus

One of the world's rarest animals, the Hainan black-crested gibbon lives only in forests on the island of Hainan in the South China Sea. They probably numbered over 2,000 during the 1950s. By 1989 most of their forest was gone, leaving 21 individuals confined to a nature reserve. The population has remained at fewer than 20 since then. In 2007 a total of 17 Hainan gibbons survived, including three newborns.

Also Extremely Endangered

These two apes, although not officially on the list of 25 most endangered primates, were noted by the list's authors as also severely threatened with extinction.

Ebo Gorilla

Gorilla gorilla

Cameroon

Scientists only discovered Ebo gorillas in 2001. But local residents have hunted them for years, and very few of these great apes survive. They're an isolated group, living apart from any other gorillas in southwest Cameroon. It's not yet known which subspecies of western gorilla the Ebo gorillas are most closely related to.

Eastern Black Gibbon

Nomascus nasutus

Vietnam, China

Eastern black gibbons once ranged widely in northeastern Vietnam and southeastern China. Much of their tropical forests got cut, and by the 1960s these gibbons were considered extinct. Thorough searching by biologists in 2002 discovered a small enclave in Vietnam. As of 2007, 54 eastern black gibbons were confirmed living in a remnant patch of forest.

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