Mandrills form the largest non-human primate troops and have complex social structures requiring sophisticated zoo management to achieve appropriate behavioral expression.
Mandrill welfare in zoos requires recognition of their extraordinary social complexity. Their wild social system — multi-hundred individual troops with complex dominance hierarchies, coalitions, and kinship networks — cannot be replicated in zoo settings. However, the welfare cost of social deprivation can be reduced by housing mandrills in stable multi-individual groups with appropriate age-sex composition. Small groups below approximately 8-10 individuals show higher aggression and behavioral abnormality than larger, stable groups. Their terrestrial foraging orientation requires ground-level foraging enrichment in addition to climbing structures. Large exhibit space allowing spatial separation during social tension is critical for maintaining group cohesion without injury. Mandrill welfare assessments incorporating behavioral diversity, social engagement quality, and facial color monitoring provide evidence-based welfare indicators specific to this species.