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| SEA LIONS |
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Family and species
-The variety of sea lions
which live at Sea Lion Caves is commonly called the Northern, or
Steller, sea lion. This sea lion is named after George Wilhelm
Steller, an eminent German naturalist who accompanied the Russian
explorer Vitus Bering in 1741 on his second Alaskan expedition.
Steller was the first qualified observer to study and classify
these animals.
The Steller sea lion is a member of the Otariidae family, or
eared seal. It is characterized by an external ear which can be
closed when entering water and by hind feet or flippers that
point forward. In contrast, Phocidae, or true seal, has no
external ears and it's rear flippers point backward. Also
belonging to the Otariidae family is the California sea lion and
the Alaska fur seal.
Physical Characteristics
- Sea Lions are mammals, or
warm blooded animals which give birth, nurse their offspring, and
must breathe air. Sea Lions are also pinnipeds -- literally,
feather-footed -- meaning they have finlike members for
propulsion. Their pelvic bone structure allows independent use of
their flippers, and therefore, they can walk on their four
weblike flippers which contain the same bony structure as the
legs of land animals. In the water, the Steller sea lion swims by
using a breast stroke and may reach a top speed of about 17
m.p.h. In contrast, other marine animals, such as the whale,
depend on fishlike body action to move through the water. The
true fur seal folds its front flippers and swims by the force of
its trailing rear flippers.
Young sea lions called pups seem to be immune to most diseases as
long as they are breast fed. As they mature, pups become
susceptible to internal parasites such as round worms and tape
worms which are a deterrent to both growth and longevity.
Population increases are also somewhat checked by adult sea lions
inadvertently trampling their young and also by accidental
drownings of the newly born which have not yet learned to
swim.
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