Sea otters are keystone species whose welfare is threatened by oil spills, fishing gear entanglement, and shark predation. Their unique biology makes them particularly vulnerable — and particularly visible — welfare victims when pollution events occur.
Sea otter welfare following oil exposure is a vivid example of how environmental pollution translates into individual animal suffering. An oiled otter experiences progressive hypothermia as its destroyed fur fails to insulate; it may also ingest oil while grooming compulsively, causing organ toxicity. Rehabilitation of oiled otters requires intensive, weeks-long care including repeated washing, assisted drying, and round-the-clock monitoring of body temperature and behaviour — a resource-intensive process that has nevertheless saved thousands of otters across multiple oil spill events. The Monterey Bay Aquarium's sea otter research and rehabilitation programme represents a model for combining individual animal welfare with population conservation. Fishing gear modification — including otter-exclusion devices and improved trap designs — reduces entanglement risk and represents a preventable welfare improvement.