Marine mammals including orcas, dolphins, and sea lions in aquarium facilities live in pool environments that represent a tiny fraction of their natural ranging areas.
Captive orcas cannot perform the long-distance swimming, complex foraging, or multigenerational social bonding that defines their existence in the wild. The dorsal fin collapse seen in virtually all captive male orcas is a physical marker of the physiological impact of captivity — the result of changed swimming mechanics in pool environments. Captive orcas live shorter lives than wild populations in many cases and show abnormal behaviors including aggression toward trainers and other orcas not seen in wild populations. The welfare case against orca captivity is among the strongest for any species.