(Molina, 1782) - Marine otter
Marine otters are very similar in appearance to freshwater otters. The snout is blunt at the tip and the nose pad is naked and relatively flat. The tail tapers to a point, typical of freshwater otters. The well-webbed feet are of moderate size, with strong claws. The coarse pelage looks rough; it has a dense underfur and a set of long guard hairs (up to 20 mm long).
Marine otters are dark brown above, a lighter fawn colour below. The muzzle, throat, and lips are not spotted, as in some other otter species. The nose pad is black, and variations in its structure may be useful in indicating stocks of marine otters (nose pad variations are used to distinguish different species within the otter subfamily).
The dental formula is I 3/3, C 1/1, PM 3-4/3, M1/2.
Can be confused with
This is the only truly marine otter along the west and southwest coasts of South America, although there are southern river otters (Lutra provocax) along some parts of the coast and marine otters enter rivers. The river otters can be distinguished by their larger size, darker colour, finer fur, and peaked nose pads.
Marine otters attain total lengths (including the tail) of slightly over 1m, and weights up to 4.5 kg.
These coastal otters are found on exposed rocky shores from the southern tip of Chile to southern Peru. They have been extirpated from Argentina.
Biology and Behaviour
Very little is known of the biology of the marine otter. They are found mostly singly or in pairs, but groups of 3 or more are sometimes seen.
The reproductive season in not well-known, but much of the breeding may occur in December and January. The usual litter of 2 pups is born after a gestation period of 60 to 70 days.
Marine otters feed on crabs, shrimps, mollusks, and fish. They sometimes enter rivers to feed on freshwater prawns.
This species has been hunted in Chile for fur and because of perceived competition with shellfish fisheries. Although legally protected, there is still some poaching.