Hippopotamuses are semi-aquatic megafauna with highly specific water, space, and social needs. Their welfare in captivity depends on access to deep water, appropriate social groupings, and management of aggression.
Hippo welfare in captivity is dominated by the aquatic requirement. Without adequate water depth and surface area, hippos cannot thermoregulate effectively, display natural resting behaviour (floating), or maintain skin health. Their secreted skin fluid, often mistaken for blood or sweat, requires moist environmental conditions to function correctly. Social management presents a significant challenge: male aggression requires careful space management and the ability to separate individuals when conflict escalates. Despite their reputation for aggression, hippos in well-managed facilities can be trained through positive reinforcement for voluntary veterinary procedures, significantly improving both welfare and safety during health monitoring.