Marine MammalsRiley, Megan, Jacob, Casey

POLAR BEARS

Top predator in the marine food chain

Adult males may reach 3 meters in length

A four-inch layer of fat lies beneath the bears skin for insulation

Can swim for up to 60 miles without resting

Eat birds and walrus pups

Currently considered endangered

A polar bear can eat 10% of it’s body weight in 30 minutes

SEA OTTERS

Spend most of their day lazily floating on their back

Found along coast of California and as far north as Alaska

Primary predators are sharks and killer whales

Consume nearly 25% of their body weight in food per day

Instead of having a thick layer of blubber, their skin is covered in a very thick layer of fur

Sea otters seldom venture a mile from shore

-They favor areas around coastal reefs and kelp bed

Whales-general           Unique characteristics:

Many behaviors used to communicateSky hopping, Breaching, Slapping, Flipper flapping, Blowhole, Blubber

Feeding:Eat krill and fish

Baleen whalesUnique characteristics:

No teethA baleen plate is composed of keratin fibers that are fused together and  there is a fringe of fibers on the back to strain plankton from the water

           Feeding:Opens its mouth and swims into dense groups of krill or schools of fish

When its mouth is full it closes it and this strains the prey after the water drains through the baleen

The retained food then moves by the tongue to the back of the oral cavity and is swallowed

Whales

Toothed Whalestoothed whalesa predatory whale having teeth rather than baleen plates. Toothed whales include sperm whales, killer whales, narwhals, dolphins, and porpoises.

• Sperm whales are the largest toothed whales and eat squid and cuttle fish

• Killer whales are the largest of the dolphins and eat seals and walruses

• Narwhals have a 3 meter tusk and live in the Canadian arctic• Porpoises look like dolphins but do not have a beak, they eat

mackerel and sardines• Dolphins are 10 feet long, eat herrings and sardines, they have been

known to save humans from drowning

SIRENIANS AND PINNIPEDS

Pinnipeds – Seals, Sea Lions, Walruses Means “featherfooted” Divided into 3 families – eared seals, true seals, and walruses True seals are also called Phocids Round head, distinct neck, large brains and well-developed

senses Body is spindle shaped, several layers of fat beneath skin Leaves water during breeding season Prey upon each other – considered to be carnivores Feed on fish, octopus, squid, krill and crustaceans Inhabit polar and sub polar regions such as the North Pacific,

North Atlantic and Southern ocean

Sirenians – Manatees and Dugongs

Dugongs

Get their name from the mythical sirens of Homer’s Odyssey

Associated with mermaids

Share similarities with whales

Completely aquatic animals – helpless on land

Feed on shallow water grasses

3 species of Manatees

The northern manatee, Brazilian manatee and African manatee

Streamlined, hairless bodies – tail fluke is a finlike structure at the posterior (rear) of sirenians

Mate and give birth underwater

Strict vegetarians

Found in South America and West Africa