otter is the largest species of the weasel family and the smallest
marine mammal. It is sociable and endemic to northern Pacific Ocean.
Three subspecies are recognized; Enhydra lutris kenyoni
occurs in Washington north through the Aleutian Islands, Enhydra
lutris lutris occurs in the Commander Islands to northern Japan,
and Enhydra lutris nereis is found in California.
centuries ago, as many as 300,000 otters lived along the shores from
Baja California to Japan. Widespread hunting beginning in 1741
extirpated the otter from most of the coast. The numbers slowly
began to recover following a treaty in 1911 between the United
States, Japan, Russia and Great Britain provided the otter with
protection from hunting. Otters are re-populating former haunts.
Most of the area west of
Prince William Sound
recolonized. In British Columbia, Alaska and Washington, populations
are growing at a rate of about 20% per year and otters are now
regularly seen in places on the west coast of Vancouver Island and a
few places on the British Columbia mainland coast. They are also
present along much of the Washington, Oregon and California coast.
The California population growth is about 5% per year.
otters distinguishable features include large flipper like hind
limbs, flattened molars and flattened tail. Males measure about 1.2
to 1.4 meters in length and females are about 1.0 to 1.4 meters
long. Males weigh up to 45 kilograms and females reach 33 kilograms.
Otters that reach adulthood can live for about 15 to 20 years in the
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