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Pinnipeds and Otters. Phylum Chordata; Class Mammalia; Order Carnivora ; Suborder Pinnipedia (means fin footed) ex: seals, sea lions, and walrus ( 33 species). General characteristics:. NOAA. - excellent swimmers. have thick layers of blubber to protect from the cold.
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Pinnipedsand Otters Phylum Chordata; Class Mammalia; Order Carnivora; Suborder Pinnipedia (means fin footed) ex: seals, sea lions, and walrus (33 species) General characteristics: NOAA - excellent swimmers • have thick layers of blubber to protect from • the cold - make a barking sound - nostrils positioned on the snout and can close for diving
The largest Pinniped is the Elephant Seal at 8,000 pounds. Pinnipeds are in 3 groups. Elephant Seals at San Simeon, CA
NOAA 1. Otariidae are eared seals that include sea lions and fur seals. They can rotate both pectoral and pelvic fins to “walk” on land. They are very social and males have huge harems of up to 100 females, which they fight to control.
2. Phocidae are true seals that have no visible ear flap. Their front legs do not rotate and will not support their weight. Because they must drag their back fins on land, seals are easy prey for polar bears, killer whales, sharks and man. In the water, they are excellent swimmers.
NOAA 3. Odobenidae - Walruses are found only in the North Polar regions. They use their tusks to hoist themselves onto the ice and to dig for clams. They can dive to 300 ft. Walrus nearly become extinction because of humans hunting the walrus for their ivory tusks. The Pinnipeds diet is mainly krill, crustaceans, mollusks, fish, and squid. Leopard Seals will eat penguins. All frequently haul-out to rest, sun, molt, breed and raise young.
Most Pinnipeds (except the walrus) are covered with dense, waterproof fur that was attractive to man. Since the Marine Mammals Protection Act of 1972, hunting is illegal. NOAA As a result, the shark has also experienced an increase in population because its food source is readily available.
Family: Mustelidae The otter is the smallest marine mammals. It is not a Pinniped, because it has four functioning limbs. Otters have a very high metabolic rate and quickly die of hypothermia when their fur is damaged. They have no blubber. Nearly 90% of the worlds’ otter population lived in the coastal waters from Prince William Sound to the Aleutian Islands.
More than 1500 otters were killed by the Exxon tanker, Valdez , oil spill. Only a few hundred otters were saved. Dozens of orphaned otters were sent to zoos and aquaria. Otter pups can’t swim so they float or rest on the mother’s stomach. Males and females only socialize for a few days a year to mate.
Otters use tools such as rocks to break open abalone. Fishermen sometimes shoot otters because their large appetites make them a competitor for abalone and fish. Declining abalone population is probably more often the result of over fishing and the destruction of habitat. Otters actually help control the sea urchin population, who are destroying the kelp beds where the abalone live.