Cetaceans and pinnipeds in captivity face welfare challenges related to insufficient space, social complexity deficits, and the profound mismatch between their natural ranging behaviour and tank environments.
The welfare science of cetacean captivity is now sufficiently developed to support clear conclusions: tanks cannot provide the space, social complexity, or environmental richness that dolphins and orcas experience in the wild. Collapsed dorsal fins in captive orca are a visible marker of chronic physiological stress related to reduced activity levels. Stereotypic behaviours in captive cetaceans — repetitive circular swimming, persistent jaw popping — indicate frustrated motivation at a scale that cannot be enriched away. The emerging sea sanctuary model — large coastal or fjord enclosures that allow semi-natural conditions — offers a welfare-superior retirement option for ex-captive cetaceans that cannot be released to the wild.