Bornean orangutans live in the tropical rainforests and swampy areas of Borneo. Their diet includes fruits, insects, leaves, flowers, bird eggs and bark. They live to be between 30 and 40 years old in the wild and up to 59 years in captivity.
Scientific & Common Names
The scientific name of the Bornean orangutan is Pongo pygmaeus. It does not have any other common names.
Bornean orangutans have coarse, orange-reddish hair and long arms that they use to move between trees. Some males have cheek pads, or flanges, and a big throat patch; these develop when the males are between 15 and 20 years old. Adult Bornean orangutans measure between four and five feet high and weigh between 73 and 180 pounds.
Bornean orangutans do not have a particular breeding season. Females breed every six to eight years and give birth to one or two offspring at a time. Their gestation period ranges from 233 to 263 days. Young orangutans stay solely under their mother’s care until they are two years old, after which they start learning to become more independent. They usually stay with their mother until they are between five and eight years old. Females set up their own territory after leaving their mother’s care, while males travel farther away before establishing their own territory.
Bornean orangutans generally live solitary lives, except for females who are caring for their young. Solitary orangutans occasionally form small groups, especially when several trees have fruited at once. Bornean orangutans spend the majority of their time in the trees and are active during the day. The main form of communication is vocalization. Flanged males perform long calls in order to announce their presence and to seek females for breeding.
Bornean orangutans were once found in large parts of southeast Asia, based on fossil evidence. They are now only found in smaller areas throughout Borneo.
Bornean orangutans are listed as endangered, mainly due to deforestation. Their range is limited because they cannot swim or cross rivers and other bodies of water. Other threats to the species include fires, habitat exploitation, pet trade, hunting and illegal logging. Bornean orangutans are protected by Malaysian and Indonesian legislation.