Sea otters are keystone species whose recovery from near extinction has transformed Pacific coast kelp forest ecosystems, with ongoing welfare threats from pollution and disease.
Sea otter welfare is threatened by environmental contamination including oil spills, domoic acid from algal blooms, and the disease Toxoplasma gondii from domestic cat faecal contamination of coastal waters. Oil-contaminated otters lose thermoregulatory ability and die rapidly from hypothermia unless captured and treated within hours. Addressing coastal pollution reduces chronic welfare threats to this keystone species.