Gibbons are monogamous, singing apes that require stable pair bonds and extensive arboreal space. Meeting their welfare needs in zoos demands careful social management and structurally complex, vertically oriented enclosures.
Gibbon welfare in captivity is dominated by two requirements: social compatibility and vertical space. A gibbon without a compatible partner is one of the most welfare-compromised animals a zoo can hold — these fundamentally social, pair-bonded animals are not adapted for solitary life. Equally, gibbons in enclosures that prevent brachiation are physically frustrated at a fundamental level. The singing behaviour of gibbons — which plays a central role in their social and emotional lives — can be monitored as a welfare indicator: pair duetting and appropriate territorial calls indicate good welfare, while suppressed or abnormal vocalisation suggests stress. Zoos holding gibbons must commit to the significant space investment these animals require.