Seals
Seals belong to the group of mammals called Pinnipeds, which means
feather footed. Within this group are the true seals which belong to the
Phocidae group, the Otariidae which include fur seals and sea lions, and the
Walrus (Odobenidae). The true seals (also called "hair" or "earless"
seals), and the sea lions and fur seals (also called eared seals) are
thought to have evolved from carnivorous ancestors, probably the Ursidae
(bears) about 25 million years ago.
All seals have torpedo-like body shapes that enable them to swim swiftly
through the water. Seals inhabiting icy regions have long sharp claws which
dig into the ice to help them climb out of the water.
TRUE SEALS (Phocidae)
All seals native to Long Island are phocid seals!
True seals include all of the five species found on Long Island in recent
years:
harbor,
grey,
ringed,
hooded, and
harp seals.
True seals have no external ear flap. Instead, they have a small flap of
skin that closes over the ear opening when they dive. Their front flippers
are short and haired and equipped with large claws, while the hind flippers
are webbed and directed backward. The rear flippers propel the seal through
the water by side to side sculling. On land these seals crawl along clumsily
by humping the body like an inchworm, but they are swift and agile in the
water, often covering long distances during migration and in search of prey.
Phocid seals are generally deeper divers than the Otariids or the Odobenids.
Seals have been recorded swimming at over 12 knots (more than 15 miles an
hour), and local fishermen have reported seeing seals over 70 miles off long
Island's shores.
EARED SEALS (Otariidae)
Not native to Long Island
Sea lions and fur seals are quite different from true seals. Their long
flexible front flippers and versatile hind flippers enable these mammals to
actually run on land and their long agile necks give them the ability to
catch objects on their nose as seen in aquariums. The fore flippers propel
the animal through the water. The males and females of most true seals are
close to the same size, whereas male sea lions and fur seals are often much
larger than the females.
Walrus (Odobenidae)
Not native to Long Island
Walrus
There are two subspecies of walruses: Odobenus rosmarus rosmarus
(Atlantic) and Odobenus rosmarus divergens (Pacific). Odobenus
from the Greek "tooth walker," probably refers to the walruses' method of
pulling themselves up onto the ice using their tusks. Today, Atlantic walruses
inhabit the coastal waters of Canada and Greenland. They had extended as
far south as Cape Cod, but were extirpated by hunters by 1800. Walruses
primarily feed on mollusks but may take other benthic (bottom dwelling)
invertebrates.
Click here for
Seal Cruise information
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