What Is a Gibbon?

A gibbon is a small primate native to expansive areas of Southeast Asia. Inhabiting tropical forests, various types of species are included in the gibbon family — Hylobatidae. The family was once separated into four separate groups, but is now part of four recognized genera that include Hylobates, Hoolock, Nomascus , and Symphalangus.

Due to their unique characteristics including the lack of a tail, the gibbon is part of the ape group known as lesser apes. Unlike the great apes, gibbons have more monkey-like features. Lesser apes have dense hair growth and are smaller in size than great apes such as gorillas. Their small size make gibbons the smallest group of the ape family.

The long arms, legs, hands, and feet of the gibbon contributes to its agile acrobatics in the overhead treetops. Their small stature, and ball and socket joints, afford gibbons masterful air locomotion, known as brachiation. Bounding from one branch to the other, gibbons can swing spans exceeding 40 feet (12 m). The gibbon’s size and agility also give it the ability to maneuver the forest’s canopies at speeds reaching 35 miles per hour (56 km/h).

Gibbons will vary in weight and height depending on the species. Small species, such as the white-handed gibbon, average 7 to 15 pounds (3 to 7 kg). The largest species, the siamang, can reach weights in excess of 20 pounds (9 kg). Gibbons average 15 to 25 inches (6 to 10 cm) in height with the exclusion of the siamang, which can exceed 30 inches (12 cm).

A majority of the gibbon’s diet consists of fruit and vegetation. It is not uncommon, however, for a gibbon to make a meal of small insects, birds, and bird eggs. Its acute ability in the overhead trees allow the gibbon to reach a variety of food sources.

Consisting of an adult male and female, and their young offspring, gibbons live in a territorial group that generally has no more than six or seven members. They are one of the very few primates that form monogamous pairs. Once the juveniles have reached maturity, they too will find a mate and create their own group. These family units will defend their boundaries vocally with amplified songs or theatrics of loud sounds unique to the gibbon.

Common to primates, gibbons are socially active within their groups. They are often seen grooming one another or sleeping together in the trees. Unlike the great apes, gibbons do not form nests for sleeping, but, rather, use branches to sleep either alone or with group members. In the wild, gibbons can reach 30 years in age, and can live roughly 10 years longer in captivity.

Gibbons are small, arboreal apes known for their incredible agility and distinctive whooping calls. They inhabit the dense tropical rainforests of Southeast Asia, from eastern Bangladesh and northeast India to southern China and Indonesia. Gibbons are integral to their ecosystems, aiding in seed dispersal and maintaining forest health.

Gibbons are set apart from other apes by their smaller size, pair-bonded social structure, and remarkable brachiation ability, which allows them to swing gracefully through the trees. Unlike their great ape cousins, gibbons have longer arms relative to their body size and lack a tail. They are also known for their loud, melodious calls that resonate through the forest.

Gibbons primarily follow a frugivorous diet, meaning they eat mostly fruit. However, they are considered omnivores as they also consume leaves, flowers, insects, and occasionally small animals. Their diet varies depending on the availability of food sources in their habitat, which can fluctuate with the seasons.

Many gibbon species are currently endangered due to habitat loss, poaching, and illegal wildlife trade. According to the International Union for Conservation of Nature (IUCN), deforestation for agriculture, logging, and human settlement is severely impacting gibbon populations, with some species like the Hainan gibbon critically endangered, having fewer than 30 individuals left in the wild.

Gibbons are renowned for their complex vocalizations, which include a variety of hoots, screams, and songs that can be heard up to 3 kilometers away. These calls serve multiple purposes, such as attracting mates, establishing territory, and strengthening pair bonds. Each gibbon species has its own unique song, which can be distinguished by its rhythm and pitch.

Gibbons are unique among apes for their monogamous social structure, typically forming long-term pair bonds. A gibbon family usually consists of a mated pair and their offspring. They are territorial and will actively defend their home range. The strong pair bond is often reinforced by duet singing between mates and mutual grooming.