Chimpanzees are our closest living relatives and among the most cognitively complex animals in zoo collections. Their welfare depends critically on appropriate social group management, cognitive stimulation, and the avoidance of early life trauma.
Chimpanzee welfare is perhaps the most ethically demanding challenge in zoo management precisely because of their cognitive sophistication. A chimpanzee understands its environment deeply, maintains complex social relationships, and can experience boredom, frustration, grief, and loneliness in ways that are difficult to distinguish from human equivalents. The welfare requirement that follows from this understanding is a high bar: appropriate social groups of mixed ages and sexes, cognitive enrichment that challenges and varies, space for species-typical ranging behaviour, and freedom from early life trauma that creates lifelong psychopathology. Infant chimpanzees raised without appropriate maternal and social contact develop stereotypies and social deficits that persist throughout their often decades-long lives — the welfare cost is severe and sustained. Sanctuaries that provide large-acreage social groups are generally considered better welfare options than most zoo facilities.