Gorillas are highly social great apes whose welfare in captivity depends critically on the composition and stability of their social group, and on environments that support their complex behavioural repertoire.
Gorilla welfare in captivity hinges on social group quality and environmental complexity more than any other single variable. Gorillas that live in stable, appropriate groups with sufficient space and diet variety are psychologically resilient and behaviourally rich. Those in unstable groups with inadequate space or monotonous diets develop stereotypies that persist even when conditions later improve. The relationship between diet and welfare is particularly well-studied in gorillas: insufficient dietary fibre and feeding time is directly linked to R/R behaviour. Zoos that extend feeding time through scattered browse, multiple smaller meals, and foraging challenges produce gorillas with dramatically better welfare outcomes than those fed two large meals on a simple fruit-and-vegetable diet.