Mandrills are the world's largest monkeys and among the most visually striking primates. Their complex social hierarchies and large group sizes create significant welfare challenges in zoo environments.
Mandrill welfare in zoos is shaped fundamentally by the contrast between their large wild social groups and the small groups that zoo spaces can accommodate. In the wild, the complex horde structure provides social choices — subordinate individuals can avoid dominant ones over hundreds of metres. In zoo groups of eight to twenty animals, subordinates have nowhere to escape chronic social pressure from dominant males and females. Enclosure design must provide multiple visual barriers, refuges, and feeding stations to distribute competition. Male-male aggression during breeding seasons can be severe and requires careful management including potential separation. Terrestrial foraging motivation — mandrills spend hours moving through forest floor vegetation — benefits from scatter feeding across large, varied substrates. Facial colour change in males provides a visible welfare indicator: extreme pallor in a normally brightly coloured male suggests stress, illness, or social suppression. Group stability over time is a key welfare asset — frequent composition changes produce sustained aggression.