Habitat

Gibbons live in the deciduous and evergreen rainforests of Southeast Asia. They are arboreal and are very rarely observed on the ground. Spending less than 1% of their time on the ground keeps gibbons safe from most of their ground-dwelling predators (Monkeyland Primate Sanctuary 2004). Gibbons are brachiators, meaning that they move from tree to tree by swinging from their arms between branches. Their long arms and thumbs attached at the wrist allow them to move quickly and agilely among the trees (Singapore Zoological Gardens Docents 2004). Gibbons are also capable of moving short distances along tree branches on just their hind legs (bipedalism), with their arms raised above their heads for balance (Singapore Zoological Gardens Docents 2004).

Photograph courtesy of S.P. Flannery <http://members.tripod.com/cacajao/index.html>

Gibbons spend their day moving within the home range and alternating between foraging and resting. This ranging behavior occurs throughout the territory, especially along the periphery, and as a result there are no designated areas for particular activities in the home range (Whitten 1982). While foraging, gibbons follow single-file, with the female usually leading (Islam and Feeroz 1992).

The typical active day of a gibbon lasts 8 to 10 hours and most of this time is spent in the “main” canopy about 20 to 35 meters above the ground (Leighton 1986). Thirty-nine percent of the day for the gibbon is spent feeding, 25 percent is spent moving from place to place, and 26 percent is spent resting (Islam and Feeroz 1992). During the day gibbons may travel anywhere from 600 to 1600 meters, with these distances varying by season and food availability (Islam and Feeroz 1992). More feeding occurs in the morning, while more resting occurs during the afternoon (Whitten 1982).

Gibbons forage throughout the day until late afternoon, when they enter ‘sleeping trees’ (Whitten 1982). Sleeping trees are the tallest trees in the forest, where gibbons can be safe from ground-dwelling predators while sleeping. Gibbons change sleeping trees frequently and the male and female typically sleep in separate trees (Islam and Feeroz 1992). No singing occurs within the sleeping trees in order to avoid being conspicuous (Islam and Feeroz 1992). Gibbons do not emerge from the sleeping trees until after dawn (Whitten 1982). While singing occurs throughout the day, gibbons most often sing during these early morning hours between 6 and 9 a.m. only after emerging from their sleeping trees (Islam and Feeroz 1992).

The most important aspects of the gibbon habitat are the sleeping trees and trees in general that keep them protected from most predators, as well as small but plentiful food patches from which they eat.