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 Otters
Sea Otter
Enhydra lutris
DescriptionDark brown; head and back of neck
yellowish or grayish. Old males may have white heads. Fairly short
tail, thick at base, gradually tapering. Feet webbed; hindfeet
flipper-like. Male somewhat larger than female. L 30–71" (760–1,810
mm); T 10 1/4–14 1/4" (260–360 mm); HF 5 7/8 –8 3/4" (150–222 mm);
Wt 25–80 lb (11.4–36.3 kg).
Endangered StatusThe Southern Sea Otter, a
subspecies of the Sea Otter, is on the U.S. Endangered Species List.
It is classified as threatened in California. Once an abundant
species, the Sea Otter was so heavily hunted for its highly prized
pelt that by 1911, when an international treaty forbade its
massacre, it had nearly become extinct. The animal was not seen in
California for many years, but in the spring of 1938, a herd
appeared in the sea south of Carmel. Today the population there is
perhaps 2,000. The southeast Alaska-Washington population seems to
be holding steady, with the exception of the region where the Exxon
Valdez oil spill wiped out thousands. The very large herds found in
the Aleutian Islands have lost some 70 percent of their numbers in
recent years, and the Aleutian population is now a candidate species
for endangered status. Killer Whales are believed to be the
culprits, feeding on Sea Otters because their traditional prey
species, the Northern Sea Lion, has become rarer. There is an
ongoing controversy between fishermen and conservationists
concerning the Southern Sea Otter. Conservationists want to keep the
animal on the Endangered Species List to ensure its protection, but
fishermen want to control the Sea Otter in order to limit damage to
abalone populations.
Similar SpeciesNorthern River Otter is smaller,
with longer tail and silver-gray throat and belly; lives mainly in
freshwater.
Breeding1 (rarely 2) pups born in winter or
spring, with fur and teeth, and eyes open. Gestation 6 1/2–9
months.
SignA loud, rapid tapping: the sound of
shellfish being cracked open on stones.
Scat: When fresh, massed
or cylindrical, thick, 4–5" (100–125 mm) long, containing bits of
shellfish or shell; crumbles easily. Occasionally found on
beaches.
Tracks: Rarely seen. Hindprint fan- shaped, 6" (150 mm)
long, almost equally wide at front. Foreprint smaller,
roundish.
HabitatCoastal waters within a mile (1.5 km) of
shore; especially rocky shallows with kelp beds and abundant
shellfish.
RangePacific Coast from California to
Alaska.
Discussion Highly aquatic, the Sea Otter eats,
sleeps, mates, and even gives birth at sea, and can remain submerged
for four to five minutes. Flipper-like hindlegs make the species
clumsy on land; it takes to the beach only to wait out storms. By
day, the Sea Otter feeds while floating on its back, sculling with
its tail. If in a hurry, it swims on its belly, using its feet and
tail like a Northern River Otter. At night, the Sea Otter wraps
strands of kelp about its body to secure its position in the kelp
beds where it sleeps. Unlike other oceangoing mammals, the Sea Otter
has no insulating blubber; air trapped in its fine fur keeps it warm
as well as buoyant. If the fur is damaged in an oil spill or by
other pollution, the otter can die from exposure or cold. The Sea
Otter is a greater user of tools than any other mammal outside the
primate family. When it dives for food, it also brings up a small
rock. It then floats on its back, places the rock on its chest, and
cracks the shell against it. Abalone, sea urchins, crabs, mussels,
and fish are the chief foods of this species. A playful animal, the
Sea Otter may interrupt a meal to dive and frolic underwater; it
consorts amiably with seals and sea lions, sometimes touching noses.
The Sea Otter watches for danger by standing in the water and
shading its eyes with both forefeet; if it spots such predators as
sharks and killer whales, it hides in kelp beds. Sea Otter pups are
weaned at one year, but may remain with their mother even after she
has a new pup. The mother floats on her back to let her offspring
nurse, nap, and play on her chest. When alarmed, she may tuck her
pup under a foreleg and dive for safety.
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