The keeping of cetaceans and pinnipeds in captivity is increasingly controversial as understanding of their welfare needs has grown.
Cetaceans in captivity cannot meet their need for large home ranges, complex social structures, and varied environments. Orca in particular live in family groups with complex dialects and long-term bonds that captivity cannot replicate. The collapsed dorsal fins seen in captive orca indicate physiological and possibly psychological stress from compromised living conditions. The welfare case against cetacean captivity is now supported by substantial scientific evidence.