Nocturnal and arboreal, it seldom descends to the ground. It sleeps curled up in the fork of a tree or clump of bamboo. It walks hand over feet over hand along branches, usually slowly by it can go faster. Though appearing slow, it can strike with speed. Gripping a branch with both feet and standing erect, it throws its body forward and seizes its prey with both hands. Adult males are strongly territorial and will not tolerate another adult male in the family group. Urine marks their territory. Vocalizations include low buzzing hiss or growl when disturbed, a single h-hi-pitched rising tone for making contact, and a high pure whistle by the female in estrus.