Sea otters are a keystone marine species whose welfare is inseparable from the health of the kelp forest ecosystems they maintain.
Sea otter welfare intersects powerfully with ecosystem health. As keystone species, their presence or absence transforms entire marine ecosystems. Oil spills cause some of the most acute welfare emergencies for sea otters — oiled fur loses insulation, causing hypothermia; oil ingestion causes organ damage; grooming behavior leads to increased oil ingestion. White shark predation is a significant welfare and population challenge for southern sea otters. Domoic acid poisoning from harmful algal blooms causes neurological suffering and death. Entanglement in crab gear and boat strike injuries affect individual animals. Rehabilitation programs for oiled and injured sea otters provide direct welfare intervention and excellent conservation outcomes.