SCIENTIFIC NAME: Symphalangus syndactylus
HABITAT: Rainforest with home range up to 100 acre tracts of Sumatra and Malaysia
CONSERVATION STATUS: Endangered
Although all gibbons call to each other, the siamangs call is the loudest and can be heard two miles away. They are especially noisy at dusk and dawn. Calling serves to announce and reinforce territories, especially to establish eating and sleeping trees, and to develop the bond between male and female. A quieter group will give way to a louder group.