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Deepseawaters
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Animals
Seals
Seals
 Seals
belong to a group of mammals known as "pinnipeds".
All pinnipeds have streamlined bodies and limbs modified into
flippers. Pinnipeds are divided into three
families: walruses, true seals and eared seals. True
seals do not have external ears, cannot turn their hind flippers
forward, and have fur on both surfaces of their flippers.
New Zealand examples include the leopard seal and
southern elephant seal.
Eared seals include fur seals and
sea lions. They have external ears, hind
flippers they can turn forward under the body and no fur on
their flippers.
A large group of seals is
called a herd and breeding colonies are called
rookeries. Adult males are called bulls and
females are called cows, while a young seal is a pup. Immature
males are sometimes called bachelors or vagrants.
Three families of living pinnipeds
are recognized, the Phocidae (hair seals
or true seals), the Otaridae (fur seals and
sea lions) and the Odobenidae (walrus). The
term pinnipedia translates from Latin as "fin foot." All of
these animals must come ashore to breed, give birth and nurse
their young, though some species are at sea for several months
at a time while others return to the shore every day.
Phocid seals include elephant
seals, several species of ice seals (some are
found in fresh water lakes) and the harbor seal of
temperate coastlines. The monk seals are found in the Mediterranean
Sea and Hawaii. Four phocid species inhabit the Antarctic
ice pack. All of these seals have a vertical undulating motion
when they move on land. The pelvic architecture does not provide
a stable anchor point for the rear flippers to engage the
ground for propulsion and the rear flippers are directed rearward.
The Otarids, fur seals
and sea lions, are found in temperate colder waters
and are associated in tropical latitudes with cold water upwelling
currents. They have external ear flaps. The arm pit or axilla
encloses the forelimbs to about the level of the forearm.
In all the pinnipeds the hind limb e.g. rear legs are enclosed
to the level of the ankle. Sea lions and fur
seals can rotate their hind feet forward and therefore
use the pelvic architecture in propelling themselves forward
with considerable speed.
The walruses, Odobenidae, are found in recent times in Arctic ice pack areas, both Pacific and Atlantic but in colonial times were found as far south as Sable Island off Nova Scotia. They are very similar to the Otarids in locomotion. Under the Marine Mammal Protection Act walruses are within the jurisdiction of the U.S. Fish and Wildlife Service.
Different Types of Seals:
 Australian Fur Seals
Carribbean Monk Seals
Crabeater seals
Elephant Seals
Harbor Seals
Hawaiian Monk Seals
Leopard Seals
Northern Elephant Seals
Northern Fur Seals
Southern Elephant Seals
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