Marine Reptiles, Birds, and Mammals Chapter 9

Marine Reptiles

Skin covered with scales-prevents water loss Eggs have leather shell to prevent water loss as well Ectotherm-body temperature fluctuates with environment

Sea Turtles Only 8 species of sea turtles Armor-like shell called a carapace Carapace fused to backbone Cannot retract head into shell Legs are modified flippers

Leave water only to lay eggs-return to same location every 2-4 years 100-160 eggs laid at a time Eggs hatch after about 60 days incubation Eggs/young are easy prey

Sea Snakes Approximately 55 species of sea snakes Ovoviviparous Carnivorous- fish/fish eggs Closely related to cobras Venomous bite

Rarely aggressive Small mouth Hunted for skin

Other Marine Reptiles Marine Iguana-basks on rocks to warm up after a cold swim. Eats seaweed and can dive up to 33 ft.

Saltwater crocodile-lives along the coast or in mangrove swamps in the Indian Ocean, Australia, and some Pacific Islands. Among the most aggressive of marine animals- more feared than sharks.

Seabirds

Endotherms- constant body temperature Waterproof feathers (oil glands) to conserve body heat Nest on land but feed mostly at sea Webbed feet Some can fly

Penguins Flightless-wings are modified flippers Spectacular swimmers Clumsy on land Adapted to cold temperatures- layer of fat under skin; waterproof feathers All but one of 18 species live in Antarctica

Galapagos penguin- equator Larger penguins feed on fish/squid Smaller feed mostly on krill Male protects the egg for 64 days Female feeds chick by regurgitating her food until about 5 1/2 months

Tubenoses Tube-like nostrils Beak curved at tip Skillful fliers Catch fish at surface or scavenge on dead birds/whales

Male/female faithful to each other Incubation of young- 8 months

Pelicans Catch fish in pouch below beak Cormorants- black, long necks, dive to pursue prey Frigate birds- narrow wings, forked tails, catch prey from surface or force other birds to regurgitate fish in mid-air

Gulls Predators/scavengers Eat fish, eggs, young, from garbage dumps, anything leftover from humans Tern is a type of gull that hovers over prey before swallowing it whole.

Marine Mammals

Endotherms Hair retains body heat Viviparous Has a placenta and mammary glands

Seals, Sea Lion, & Walruses Pinnipeds Have paddle shaped flippers for swimming Rest/Breed on land Predators (fish/squid) Layer of blubber under skin acts as insulation, provides buoyancy, and is a food reserve

Males called bulls; females called cows Main difference between a seal and sea lion- seal cannot move rear flippers forward Walrus has large tusks and feeds on invertebrates, mainly clams

Sea Otters Smallest marine mammal Lack a layer of blubber Dark brown fur attracts hunters Became almost extinct until protected in 1911 Playful and intelligent

Spend most of time in water other than breeding and giving birth Live around kelp Eat clams, mussels, crabs, sea urchins, and fish

Manatees (Sea Cows) Front flippers only Gentle, peaceful Live in groups Strict vegetarians Hunted for skin, meat, and oil Reproduce slowly- 1 calf every 3 years All 4 species in danger of extinction

Whales, Dolphins, and Porpoises are in a group called the Cetaceans Spend entire life in water Breathe air- can drown “warm blooded” Produce milk for young

Front flippers only Have a dorsal fin Blubber provides insulation Nostrils form a blowhole About 90 species, other than 5 species of freshwater species

Two categories of cetaceans: toothless, filter-feeding whales toothed, carnivorous whales

Toothless, filter-feeding better known as baleen whales baleen is a flexible, fibrous plate that hangs from upper jaw

made of same material as hair and nails feed by taking a mouthful of water and squeezing it through bristles- filter feed largest animals on earth two blowhole’s

blue whale is the largest whale of all- males average 80 ft and females 110 ft other types of baleen whales- fin, humpback, right, bowhead, gray

Toothed, carnivorous teeth adapted for fish, squid, and other prey teeth only used to catch prey- food is swallowed whole one blowhole largest of this group is the sperm whale

material from squid beaks found in stomach called ambergris- used in perfume killer whale is black/white and has a taste for seals, penguins, sea otters, and even other whales

no confirmed cases of attacks on humans Although small- dolphins and porpoises are whales

Dolphins/Porpoises: Playful Social Easily trained Travel in “pods”

Whaling- whale hunting: In the 1600’s Europeans exploited whales Harpooned from small open boats- In 1800’s harpoons were attached to explosives Blubber provided oil for soap and lamps Killed for meat

Whales have a very low reproductive rate (about 2-3 years) so this devastated the population Some nations even developed ships that could process carcasses at sea. Blue whales were a prime target. One whale yielded 9000 gallons of oil.

80% of the whales caught were sexually immature 80% of the whales caught were sexually immature. This added to decreasing number. 1946-20 nations developed the IWC (International Whaling Commission) to regulate over fishing IWC set annual quotas for the # of whales to be killed

Demand for whale products decreased due to replacements, so in 1972 the Marine Mammal Protection Act of 1972 banned all hunting of marine mammals. The affects of whaling are still being felt.