Sea Otter

The sea otter is a marine mustelid with a broad whiskered muzzle, webbed hind feet and exceptionally dense fur that traps insulating air. Adult males reach about 148cm and 27–38.6kg; females about 140cm and 16–27kg (National Museum of Nature and Science, Marine Mammals Information Database). Unlike seals it commonly floats on its back at the surface, where the forepaws remain free to handle food and groom the coat.

After disappearing locally, sea otters have begun recolonising the coast of eastern Hokkaido in recent decades. Observed prey there include bivalves, sea urchins, crabs, snails and chitons, taken from the seabed in shallow coastal water (Ochi et al. 2024). Sightings remain concentrated along eastern Hokkaido and should be watched from a respectful distance without approaching resting animals. The species is nationally Critically Endangered (Japan MOE Red List 2020).