Class Mammalia All mammals share the following characteristics: Warm-blooded (endothermic and homeothermic) Four-chambered heart Fur or hair (not feathers) to retain heat Mammary glands to produce milk for young

Photographs are property of the Riverhead Foundation Marine Mammals In the United States, marine mammals are protected by the Endangered Species Act of 1985 and the Marine Mammal Protection Act of 1972 Prohibits the capture, harming and/or killing of any marine mammal RF has special permits to handle marine mammals and is the only stranding program in the state of NY Photographs are property of the Riverhead Foundation

Seals, Sea Lions, and Walrus Members of the order Pinnipedia are nearly exclusively marine Pinnipeds include: Seals Sea lions and fur seals Walruses

Seals, Sea Lions, and Walrus They are predators, feeding mainly on fish and squid Streamlined bodies for swimming Thick layer of fat, or blubber for insulation, food reserves, and buoyancy

Sea lions and fur seals vs. Seals Sea lions and fur seals (Otariidae) Seals (Phocidae)

Photograph is property of the Riverhead Foundation Seals Seals (earless pinnipeds; family Phocidae) have 19 representative species Rear flippers cannot be moved forward No external ear flap Claws (and fur) on flippers Short, robust neck Photograph is property of the Riverhead Foundation

Sea lions and fur seals Sea lions and fur seals (eared pinnipeds; family Otariidae) have 15 representative species Rotatable hind flippers External ear flap Long, flexible neck No fur or claws on flippers

Walrus Walrus (family Odobenidae) are large pinnipeds with a distinctive pair of tusks Both male and female have tusks; can reach 1 meter in length! Used for defense, and anchoring onto ice Strictly Arctic! Benthic-feeder; feeds primarily on clams “tooth walk” for observing walrus pulling themselves out of water with tusks

Sea Otters and Polar Bears Sea otters and polar bears are marine mammals belonging to order Carnivora The sea otter is the smallest marine mammal, which lacks a layer of blubber Instead, the sea otter has extremely dense fur, which traps air against the body for insulation Hunted extensively for fur nearly to extinction 1.000.000 hairs per square inch!

Sea Otters and Polar Bears Sea otters are found only in the Pacific Ocean, and have the densest fur of all animals Sea otters inhabit nearshore environments and dive to the sea floor to forage on mollusks, crustaceans and echinoderms (sea stars and urchins) Must eat ~25-30% of their body weight per day

Sea Otters

Polar Bear Polar bears are semi-aquatic mammals that spend a good deal of their life drifting on sea ice in the Arctic They feed primarily on seals, which they stalk at breathing holes World’s largest land carnivore Thick blubber; translucent fur, black skin! Threatened by the loss of Arctic sea ice!

Manatees and Dugong Sirenians (order Sirenia) include the manatees and dugong Sirenians, also known as sea cows, have a pair of front flippers, but no rear limbs Swim with up-and-down strokes of their paddle- (manatee) or V- (dugong) shaped tails Closest land relative is the elephant!

Manatees

The Florida Manatee

Dugong

Manatees and Dugong Sirenians are the only herbivorous marine mammals; feed on aquatic plants and algae Some species live in fresh and/or brackish water Inhabit temperate or subtropical waters Severely threatened by motor boat collisions, harmful algal blooms, pollution, and severe winters