Animal Data > Siamang Gibbon

(Hylobates syndactylus)

There are twelve species of gibbon of which six are endangered. They are part of the group known as the lesser apes and, like all apes, have no tail.

Siamang gibbons live in evergreen tropical rainforests in SE Asia. Much of a siamang gibbon's life is spent in the tree canopy where their long arms allow them to swing from branch to branch. They use their long fingers to hook over the branches as they swing rather than grasping. When branches are too big to swing on, a gibbon will walk, holding its hands above his head for balance.

Siamang gibbons are active during the day. Their diet consists mainly of leaves and soft fruits, but flower buds and insects are also eaten.

Siamang adults pair for life. They live in small family groups of parents and immature offspring. One baby is born and clings to its mother for about a year, at which time parental care transfers to the father. Grooming and play help keep the group together. Singing is also thought to aid bonding as well as protecting territory. The female calls with a series of barks and booms and the male then joins in with a loud scream. These calls can be heard up to 5km away.

Siamang gibbons, like a lot of other animals, are threatened by the destruction and fragmentation of their forest habitat.

Main Features

Gibbons are notable in that they have very long arms. Most gibbons have vocal sacs, which they use to make their calling louder. Siamang gibbons sing for about 15 minutes several times a day.

Fairly long black hair with grey face. Long arms and vocal sac on throat. webbing between 2nd and 3rd toe. Male and female are the same size.

In Captivity

The siamang gibbons at Marwell are fed on fruit, vegetables and bread. Their cages are furnished with ropes so that they can swing, and from time to time the arrangement of these is altered to enrich the gibbons' environment.