How modern zoo hippo keeping is evolving to meet the complex social, thermal, and behavioral needs of these semi-aquatic megafauna.
Hippopotamus welfare in zoo settings is severely compromised when exhibit design fails to accommodate their fundamental biological requirements. As obligate semi-aquatic animals, hippos that cannot fully submerge experience thermoregulatory stress, skin deterioration, and behavioral frustration. Territorial animals kept in confined spaces with incompatible companions face injury risk and chronic social stress. The small number of hippos held in European zoos amplifies welfare concerns - each individual represents a significant proportion of the captive population, and poor welfare affects a large proportion of the total. Investment in appropriate housing for the few hippos in captivity is an ethically significant welfare obligation.