Bornean Orangutan

Bornean Orangutan


Most of lowland Borneo.


All levels of lowland primary rain forest. Almost totally arboreal. Rivers and streams make natural boundaries.


Coloration of the orangutan varies from orange to brown to maroon. From the top of the head a fringe of hair lies toward the forehead. On the arms the hair runs in both directions toward the elbow to help shed rainwater. Orangutans have an almost hairless dished face except that adults have whiskers on the cheek and chin. The skull is narrow and heavy. No neck is visible. Muzzles are massive, rounded and protecting. Adult males have fatty flanges around the deep-set eyes and a throat pouch of large laryngeal air-sacs which extends under the arms and over the shoulders. This enables the male's voice to carry half a mile. The orangutan has long arms and short legs. Legs may go at right angles to the body for better maneuverability in the trees. Hands are long, slender and prehensile with curved fingers. The thumb is short and set close to the wrist. Feet are hook-like with a reduced big toe similar to hands. Fingers and toes show strongly curved nails. Lifespan is 30 years in the wild, 50 years in captivity. There is obvious sexual dimorphism.

Bornean Orangutan

Brachiation in trees involves the use of all limbs, with the feet as effective as hands. Movement is cautious in adults with no leaping or jumping. They may make young trees sway dramatically in order to reach the next tree. On the ground, orangutans walk quadrupedally with feet clenched and 'knuckle-walking.' Groups consist of an adult female with one or two young. Males are generally solitary, avoiding other males of their species by bellowing, branch-shaking, branch-throwing. Males may sometimes become nomadic and leave their native territory. Sometimes adolescents (beginning about five to eight years of age) of both sexes may travel in twos and threes. Nests are in closed canopy, 20 to 80 feet above the ground, made with large branches and leaves and sometimes a 'roof.' A new one is generally made every day. Some tool use has been recorded: using a forked stick to reach other trees, using sticks as levers, and using large leaves as umbrellas.


The males find females by calling for them. Menstrual cycle runs 30 to 35 days. There is no sexual swelling during estrus, but shows slightly during pregnancy.  Gestation lasts about 244 days. One baby is born, rarely two, any time of the year. Birth weight is about four pounds (1800 grams). Babies are born approximately every five years; the mother does not conceive while she is nursing. Mothering is a learned behavior. The baby begins to cling to its mother during the first day or two. After approximately one year, the baby begins to eat solid food. The baby is weaned at about three years and reaches sexual maturity in females at about six to seven years, and in males about ten years. Cheek flanges occur at about 12 to 14 years at which time the males become more solitary.

Interesting Facts:

There are two subspecies of orangutans, the Bornean (P. p. pygmaeus) and the Sumatran (P. p. abelli), which has hair which is longer and lighter. Orangutans developed earlier than gorillas and chimpanzees. Their prehistory covers a wider range than they now inhabit. Some people consider orangutans more intelligent than chimpanzees.

All training at Utah's Hogle Zoo is done through positive reinforcement. Our apes are trained everyday through protected contact, which means that there is always a barrier between the keepers and the apes for safety. The apes have learned behaviors such as open mouth, teeth brushing, body part presentation and injection. These behaviors all help with the daily and medical care for the animals.

Enrichment is novel items added to an animal's environment to encourage natural behaviors and stimulate the mind , such as climbing, foraging and investigation. The enrichment that we provide the apes is not always food related. Bubbles, sheets, paper bags, barrels, puzzle feeders, and a variety of scents are just a few of the over 200 creative items we utilize for ape enrichment.

About Our Animals:

The Zoo has three orangutans, one female and two males.

  • Acara (female) was born at Hogle Zoo May 7, 2005. Acara was born via caesarian section and was rejected initially by her mother, Eve. After nine months of hand raising and training, Acara was returned to her mother full-time and lived with her happily until Eve passed away in 2014 shortly after the birth of Tuah
  • Tuah(male) was born November 4, 2014 and is the offspring of Eli and Eve (both passed away in 2014) With the untimely death of his mother, Tuah had to be hand-raised by Zoo keepers. Acara has proved to be an attentive sister and after a lot of work and training Tuah was place with Acara full-time in March of 2015.
  • Mia(male) was born at Cheyenne Mountain Zoo July 8, 1989. He came to Hogle Zoo from Greenville Zoo in 2016 to be a companion to Tuah and Acara. Mia is very laid-back and loves food. He’s been a great addition to our orangutan group and is often seen wrestling and playing with Tuah.

Acara and Tuah, though both having to be hand-raised for a time by their keepers, are now enjoying life together. This is due in a large part to the hundreds of hours of dedicated work and training on the part of their devoted keepers.

Bornean Orangutan

The major threat to Orangutans of Sumatra and Borneo is the development of palm oil plantations. Palm oil for our consumption is harvested in the last remaining home of wild orangutans. The severe decline of orangutan populations is a direct result of the palm oil industry. Destruction of habitat, leading to their starvation, and the deliberate killing of orangutans who venture onto palm oil plantations are the main reasons for the decline of 50% of Sumatran orangutans in the last eight years. Some experts predict that the palm oil industry will drive orangutans to extinction within ten years.

To learn more about palm oil and orangutans, visit www.orangutan.com and www.redapes.org

Did YOU Know?    
Orangutan means the person of the forest in the Malay language.
Bornean Orangutan
Class: mammals
Order: Primates
Family: Pongidae
Genus: Pongo
Species: pygmaeus
Height: Males: ~37 inches - Females: ~31 inches
Weight: Males: up to 300 lbs. Females: 90 - 140 pounds
Average Lifespan: 40-50 years
Wild Diet: Predominately fruit, particularly mangoes, durian, and figs. Also ants, termites, honey bees, small reptiles, birds and amphibians. During monsoon season, the orangutan may supplement its diet with leaves, bark, and pith.
Zoo Diet: Apples, bananas, oranges, monkey chow, carrots, kale, spinach,yams and celery.
Predators: Leopard, and man through poaching and logging.

This is an ssp animal

USFWS Status: Not Listed
CITES Status: Appendix I
Where at the Zoo? Great Ape Building

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