Drill monkeys are among Africa's most endangered primates with complex social structures. Captive breeding contributes to conservation while welfare-focused management enables natural behaviour expression.
Drill welfare in captivity depends critically on social group management. Drills live in large, complex groups in the wild — captive populations housed in pairs or small groups deny the social behaviour that constitutes the majority of their natural day. Male management is particularly challenging: dominant males in small groups may prevent subordinate males from accessing food and females, creating chronic stress. Large, naturalistic enclosures that allow subordinate males to avoid dominant individuals are welfare requirements for multi-male drill groups. The conservation rationale for captive drill management is strong given wild population status, but welfare must not be sacrificed to population goals — stressed, behaviourally abnormal captive drills contribute poorly to conservation outcomes.