Order: Carnivora
Family: Mustelidae
Genus & Species: Enhydra lutris nereis
APPEARANCE
Southern sea otters are a distinct subspecies of the sea otter and can be
distinguished from the other subspecies by its size, the shape of its skull, its
geographic range, and the food it eats. Southern sea otters tend to be
smaller than northern sea otters and grow to roughly 3.3 ft in length, with a
14 in long tail. They weigh up to 80 lbs, the males being heavier than the
females. The guard hairs are long and water resistant; without them the
southern sea otter would die. The underfur is soft, silky and velvety to the
touch. The back is usually black or dark brown, the belly, neck and face
lighter. The forearms are short and stubby and end in small claws. The back
feet are longer and webbed, shaped like flippers. The ears and the eyes are
small and the nose diamond-shaped. Below the nose is a "moustache" of
whiskers.
Southern sea otters swim on their backs and use their rear flippers to move
and their tail to steer. They can swim up to speeds of 1.5 mph.
Southern sea otters have a life span of up to 20 years, with an average of 8
years in the wild.
HABITAT
Southern sea otters are found in the north Pacific off the coast of central
California. They are found from Aņo Nuevo (near Santa Cruz) to Purisima
Point. Another colony lives off San Nicolas Island. Southern sea otters used
to range from British Columbia to Baja, California. Due to overhunting,
they are now restricted to a 250 mile range. Efforts are being made to return
them to Washington and Oregon, but so far this has been unsuccessful.
Southern sea otters live no farther than 3 miles from shore. They are found
in kelp forests, where they play a vital role in their community. They are
found in groups called rafts that vary from 10-100 individuals. To sleep they
wrap themselves in kelp so as not to float away.
FOOD
Southern sea otters feed on 40 different species of marine animals, mainly
purple sea urchins and fish. They also feed on crabs, abalones, snails,
starfish, clams, and mussels. They capture their prey with their forearms
and will use rocks to break open the shellfish. They feed while floating on
their backs. To eat crabs, they set the crab on their belly and pull its legs off
one by one as the crab scurries around.
Southern sea otters play a vital role in their community by controlling the
purple sea urchin populations. Without them, the urchins would overgraze,
disturbing the kelp bed's anchors. The kelp would break free and float to
the surface, exposing to predators all the animals that lived in the kelp
forests.
BREEDING
Southern sea otter females reach sexual maturity at the age of 4. They mate
at any time of the year, the males with more than one female. One,
sometimes two, young are born every two years. The males take no
involvement in raising the young. The pups are born with their eyes open,
their bodies fully furred, and their mouths with a full set of milk teeth. They
cannot swim, only float, and so love on the mother's belly for the first two
months of their lives. They are independent hunters at 7-8 months.
ENEMIES
Southern sea otters are sometimes hunted by killer whales and great white
sharks. Oil spills and other forms of pollution can kill them off in large
numbers.
In the 1700's there were hundreds of thousands of southern sea otters living
along the California coast. By the late 1800's, however, they were virtually
wiped out by fur hunters. They were thought to be commercially extinct
until a raft of 300 southern sea otters was discovered near Big Sur. This
single group is responsible for all the southern sea otter alive today, which
numbers at roughly 2300.
In spring of 1998 a survey was taken of the southern sea otter populations.
For some unknown reason there was a 5.2% decline in the population since
1997. This is the third year a decline has been noted. The pup count also
showed a decline, a staggering 48.7%, the highest yet since 1982. Again, it is
not known why.
Southern sea otters are classified as a threatened species.
RELATIVES
There are two other subspecies of sea otter, the northern (Alaskan) sea otter
and the Russian sea otter.
RESOURCES CITED
1. www.enn.com/enn-news-archive/1998/06/060998/otters.asp
2. www.execulink.com/~ngamble/otter1.htm
3. www.seaotters.org/index2.html
4. www.ghs.com/people/jimmy/ottertx1.html
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