Giant otters are highly social, vocally communicative mustelids whose captive welfare depends on group size, aquatic access, and social stability.
Giant otter welfare in captivity is strongly influenced by social group cohesion and aquatic access quality. Wild giant otters are among the most socially complex mustelids — family groups hunt cooperatively, communicate through a rich vocal repertoire, and maintain territories together. The welfare consequence of inadequate social conditions is chronic stress expressed through elevated aggression, reduced feeding, and stereotypic behaviour. Aquatic access quality matters beyond simple water provision: giant otters need sufficiently deep, clear water to perform the diving and underwater pursuit that their foraging system requires, and water quality maintenance for highly active, semi-aquatic species is demanding. Prey-in-water feeding enrichment — fish released into the pool for active pursuit — partially activates the hunting sequence that occupies much of wild giant otter daily activity.