Stellar
Sea Lions
Stellar
Sea Lion
(Eumetopias jubatus)
Life span 30 years
Size and Weight
Male (bull): 3m, 1000kg,
Female (cow): 2m, 300kg.
Physical Appearance
Steller sea lions are the largest of the sea lions. They are born with
a dark brown coat that becomes a reddish-brown as they develop into
adults.
Distribution
Steller sea lions inhabit the cooler waters of the North Pacific. They
are divided into two stocks - the 'western population' (Gulf of Alaska,
Bering Sea, Russia and Japan), and the 'eastern population' (California,
British Columbia and south east Alaska)
Diet
Steller sea lions feed near the shore on squid, octopus and fish, such
as herring, mackerel and salmon.
Social organization and behaviour
They have also been known to hunt northern fur seal pups and harbour
seals. They are hunted by sharks and killer whales. Steller sea lions
are known to make dives of 400m in search of food.
Males are polygamous and territorial on land. They defend the boundaries
of their territories with ritual threat displays to other males.
Reproduction
The females give birth to one pup that is nursed for at least a year,
sometimes for up to three years. After 9 days of giving birth, the females
may spend 1-3 days in the sea - feeding, and then will return to her
young for a further few hours before returning to the sea.
She will carry out this ritual until the pup is a month old, and will
be able to join her in the sea.
Conservation/status
Steller sea lions are on the IUCN Red List as Endangered. The western
population has been decreasing in numbers. This may be due to declining
fish stocks.
Since 1990, no-trawl buffer zones of 10 nautical miles (N.M.) and 20
N.M. around various Steller sea lion rookeries have been established
by the U.S. Sea lions are killed annually for subsistence by Aleutians
in Alaska.