Sea otters have recovered dramatically from near-extinction but face ongoing welfare threats from oil spills, shark predation, and entanglement. Their role as keystone species amplifies their ecological welfare significance.
Oil-contaminated sea otters experience hypothermia as their fur loses insulating capacity, followed by organ failure from attempting to clean toxic oil by grooming. The Exxon Valdez response demonstrated that intensive rehabilitation — cleaning, rewarming, and intensive care — can save oiled sea otters, but the welfare harm during the cleaning process is significant. Shark-bitten otters that survive initial attacks die from shock or infection over subsequent hours. Entanglement in crab pots and fishing gear is an emerging threat as otter range expands into fishing areas. Despite these threats, sea otter recovery represents one of the most successful marine conservation stories — with significant welfare co-benefits from reduced hunting pressure.