By Sara Crane
Geographic Range
Hylobates concolor is found in mainland southeast Asia, east of the Mekong River in the Yunnan province of China, also in Laos, and Vietnam north of the Red River. There is also a population on Hainan Island (China).
Habitat
Hylobates concolor is arboreal, spending most of its time in the canopy of the rainforest. It rarely stays on the ground for very long.
These animals are found in the following types of habitat:
tropical ; terrestrial .
Terrestrial Biomes:
rainforest .
Physical Description
(11 to 17.6 lbs)
Hylobates concolor are between 44.1 and 61 inches high and weigh approximately 5 to 8 kg. At birth, the coat of H.concolor is is a buff or golden color. After an individual reaches about six months of age, the coat turns black. Males remain black and have whitish fur around their cheeks and on the top of their heads. The fur of females reverts to a golden or buff color when sexual maturity is reached, sometimes with black patches.
The body is small with an erect posture. Arms are long and legs assist in brachiation. Hook shaped hands assist in locomotion as well. The thumb extends toward the wrist. This allows a better range of motion for traveling and feeding.
Males and females are about the same in size and shape.
Some key physical features:
endothermic ; homoiothermic; bilateral symmetry .
Sexual dimorphism: sexes alike, sexes colored or patterned differently.
Reproduction
These gibbons produce one young every two to three years.
Gibbons do not breed seasonally.
Hylobates concolor is monogamous.
Mating systems:
monogamous .
Sexual maturity is reached at about eight years of age. Mated pairs have one young every two to three years. The gestation period is between seven and eight months. Nursing lasts about two years. Most gibbons reach sexual maturity around 8 years of age.
Key reproductive features:
iteroparous ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization ; viviparous .
Females nurse their young until the young are about 2 years old. Males as well as older infants and juveniles assist with care.
Parental investment:
altricial ; pre-fertilization (provisioning, protecting: female); pre-hatching/birth (provisioning: female, protecting: female); pre-weaning/fledging (provisioning: female, protecting: male, female); pre-independence (provisioning: female, protecting: male, female); post-independence association with parents; extended period of juvenile learning.
Lifespan/Longevity
The reported lifespan for other species in the genus Hylobates is 44 years in captivity. Mated pairs are known to have lived at least 25 years in the wild. It is likely that H. concolor is similar.
Behavior
Hylobates concolor lives in small family groups with the monogamous male and female and from one to four of their offspring. They are very territorial and occupy an area of about eight or nine acres, defending it from intrusion by other gibbons by very loud calls. Males also chase intruders off of the territory.
The calls are also used in attracting mates or bonding with a current mate. These calls or songs are made by both the males and females.
Families come together to groom, rest, and sleep.
Communication and Perception
All primates show complex communication involving vocalizations, physical contact, and visual signals, such as facial expressions and gestures.
Other communication keywords:
duets .
Food Habits
Diet consists of fruit (prefering it to be pulpy and ripe), young leaves, buds, insects, and occasionally invertebrates.
Families often feed together in the trees.
Animal Foods:
insects.
Plant Foods:
leaves; fruit.
Predation
Predation on these animals has not been reported. Because they spend so much of their time high in the canopy, where branches are too thin to support heavy predators, these gibbons are protected from many potential predators. It is likley that humans, snakes, and raptors are the greatest threats to these primates.
Ecosystem Roles
These animals are likely to be important in dispersing the seeds of those plants upon which they feed.
Economic Importance for Humans: Negative
There are no known adverse effects of Hylobates concolor on humans.
Economic Importance for Humans: Positive
Hylobates concolor has educational and entertainment value to humans, and they can be seen in some zoos around the world. They are sometimes exploited for pets and food.
Conservation Status
Hylobates concolor's endangered status is due largely to destruction of habitat from development and logging. Military activities have also caused a decline in this species.
Contributors
Nancy Shefferly (editor), Animal Diversity Web Staff.
Sara Crane (author), University of Michigan.
Phil Myers (editor), Museum of Zoology, University of Michigan.