Orangutan

Category: Wildlife

Orangutans live in the tropical rainforests of Borneo and northern Sumatra. The Bornean species is also found in swampy areas. Orangutans live on fruits, insects, leaves and flowers. Their lifespan in the wild ranges from 30 to 40 years, while they live up to 60 years in captivity.

Bornean Orangutan

Bornean Orangutan

Male Orangutan

Male Orangutan

Female Orangutan with Baby

Female Orangutan with Baby

Baby Orangutan

Baby Orangutan

Scientific & Common Names

Kingdom - Animalia

Phylum - Chordata

Class - Mammalia

Order - Primates

Suborder - Haplorhini

Family - Homonidae

Subfamily - Ponginae

Genus - Pongo

Species & Common Names - P. abelii (Sumatran Orangutan), P. pygmaeus (Bornean Orangutan)

Characteristics

Both species of orangutans have red hair covering their bodies, legs, head and long arms, but Bornean orangutans tend to have darker red coats and thicker hair. Sumatran orangutans have longer, finer hair and white hair on their face and groin. They’re thinner than Bornean orangutans, with adults weighing between 66 and 198 pounds and measuring 4 to 6 feet in length. Adult Bornean orangutans weigh an average of 191 pounds and measure 3 to 4 feet in length.

Breeding

Bornean orangutans breed all year round, while Sumatran orangutans breed during the rainy seasons. Females of both species have an average gestation period of 245 days and give birth to one or two offspring. Sumatran orangutans don’t become independent until they’re 8 or 9 years old, while Bornean orangutans become independent when they’re between 5 and 8 years of age.

Behavior

Both species of orangutans are mostly solitary, although Sumatran orangutans are a bit more social than their Bornean counterparts. Orangutans in general spend a lot of their time in trees and are mainly active during the day. When they interact with others, they do so through occasional play and vocalization. They also engage in nonsocial play and grooming and are known for being highly intelligent. They make a wide range of facial expressions as well.

History

The Sumatran orangutan used to be considered a subspecies of the Bornean orangutan, but it now has its own classification as a separate species. Sumatran orangutans have lost more than 80 percent of their population during the last 75 years and are now found only in the northernmost part of Sumatra. Bornean orangutans have declined by more than 50 percent over the last 60 years.

Present Status

Sumatran orangutans are classified as Critically Endangered, with roughly 7,300 remaining in the wild. Bornean orangutans are listed as Endangered and number between 45,000 and 69,000 in the wild, according to the most recent estimates. Deforestation, mainly through logging, is the main cause of decline for both species. Both are protected by domestic legislation.