Marine Biology Flashcards

Flashcards covering the key topics in the Marine Biology lecture notes, designed to help students review for their upcoming exam.

Marine Mammals Characteristics

Hair, warm blooded, live birth w/ a placenta, and mammary glands.

Marine Mammals Reproduction

Internal fertilization, most have only one baby at a time, some of the larger animals only reproduce every 2 or 3 years.

Marine Mammal Protection Act

Protects marine mammals, making it illegal to approach, harass, or bother them, with stiff fines and/or possible jail time for violations.

Order Sirenia Animals

Manatees and Dugongs

Order Sirenia Habitat and Diet

Live in shallow tropical waters and are large, slow-moving vegetarians that have earned them the nickname “sea cow”

Manatees

Lounging at the surface may be responsible for sailors’ tales of seeing mermaids after long voyages.

Order Carnivora Animals

Polar bears, sea otters, and the pinnipeds

Order Carnivora Diet

These animals all eat fish, mollusks, and in the case of bears, pinnipeds.

Order Carnivora Examples

Polar bears, Sea Otters, Walrus, Elephant Seals, Steller Sea Lions.

Polar Bears Characteristics

Largest bear species, are solitary except for breeding, can be very aggressive.

Sea Otters Behavior

They will use kelp beds to keep them from floating away.

Pinnipeda Meaning

Flipper Feet

Pinnipedia Examples

Seals, Sea Lions, and Walrus.

Pinniped Anatomy

Legs are modified into flippers to help them swim even though they spend time out of the water.

Pinniped Diet

Fish eaters and many are capable of deep diving.

Pinnipeds Insulation

Blubber covered by dense fur insulates them and gives buoyancy.

Pinniped Social Behavior

Live together in larger colonies, breeding colonies are called “rookeries”. One male will keep a harem of several females.

Seals Characteristics

Small flippers and no ear flaps, they drag themselves on their bellies.

Sea lions Characteristics

Larger flippers can hold themselves up with their front flippers, allowing them to “walk”, have ear flaps

Order Cetacea Examples

Dolphins, porpoises, and whales.

Order Cetaceans Communication

Use a “melon” on their forehead for communication and hunting.

Baleen Whales

Suborder Mysticeti

Suborder Mysticeti Characteristics

Largest cetaceans and feed primarily on krill (small shrimp), small crustaceans, and other plankton.

Suborder Mysticeti Anatomy

They have no teeth, instead they have baleen - comb like fibers that filter the plankton out of the water.

Suborder Mysticeti Feeding Strategies

Different whales have different feeding strategies - some gulp, each some swim with their mouths open (skimming), others suck at the bottom mud.

Toothed whales

Suborder Odontoceti

Suborder Odontoceti Examples

Dolphins and porpoises.

Suborder Odontoceti Diet

Fish, squid, and seal eaters.

Narwhals Characteristics

7-10 foot long tooth that extends outwards from its head.

Marine Mammals Deep Diving

Hyperventilate while resting then take a deep breath while resting. This results in super-oxygenate in blood. Lungs collapse under pressure >100m. Allows little compressed gas into the bloodstream, preventing the bends. Heart rate slows and arteries constrict.

Marine reptiles Types

Iguanas, Sea turtles, Sea snakes, and Saltwater crocodiles

Marine Reptiles Anatomy

Breathe air from the surface (have lungs). Have scaly skin and claws (except snakes)

Marine Reptiles Reproduction

Most lay leathery shelled eggs (on land)

Marine Reptiles Behavior

Cold-blooded - must come ashore or rest near surface to warm up

Marine Reptiles Salt Regulation

Special nasal glands and kidneys to help with salt. Kidneys create a uric acid paste which mixes with feces for elimination, Salt excretory gland above the eye - salt is either blown or drips out.

Marine Iguanas Habitat

Found on the Galapagos Islands, off the western coast of Ecuador.

Marine Iguanas Diet

Vegetarians, swimming in the surf to pick algae off the rocks.

Marine Iguanas Adaptation

Flattened tail and strong claws help them get back onto shore.

Marine Iguanas Behavior

Warm themselves up on the rocks and short excess salt out of their nose.

Sea Snakes

All are venomous

Sea Snakes Habitat

Live in the South Pacific and Indian Oceans only.

Sea Snakes Family

Members of the Cobra family

Sea Snakes Adaptation

Laterally flattened tail to help them swim.

Sea Snakes Behavior

Come ashore to warm up

Sea Snakes Reproduction

All but one is viviparous

Sea Snakes Threat

Most people who are bitten by them are fisherman or beachgoers by different circumstances

SW Crocodiles Threat

Responsible for eating the most people

SW Crocodiles Habitat

Australia, where they hang out in brackish water or estuaries

SW Crocodiles Reproduction

Crocs come ashore to mate & lay eggs, and the female guards the nest and moves the hatchlings to water

# Number of species of sea turtles

7 species

Sea Turtles Adaptation

Hydrodynamic shell and legs modified into flippers

Sea Turtles Behavior

Only come ashore to lay their eggs - entire life is spent at sea

Sea Turtles Threats

Endangered from…turtle soup, predators, fishing nets, being entangled in plastics

Shorebirds migration

Most migrate from the arctic to South America each year.

Waders Characteristics

Marine birds, long legs and necks

Pelagic Birds Behavior

Birds that only come ashore to nest

Falconiformes Examples

Eagles and osprey

Penguins behavior

Birds that don’t fly

Pelagic Birds Examples

Magnificent frigatebird, Laysan Albatross, Albatross Chick and Adult, Blue-footed Booby

Near-Shore Birds Examples

Common Tern, Red-Billed Tropicbird, Herring Gull, Greater Black-back Gull

Raptors Examples

Northern Harrier, Steller's Sea Eagle, Osprey

Sea Ducks Examples

Bufflehead, Common Goldeneye, Common Elder

Waders Examples

Clapper Rail, Great Egypt, Roseate Spoonbill, Tricolored Heron, Glossy Ibis

Shorebirds Examples

Black Skimmer, Red Knot, Piping Plover, American Oystercatcher

Penguins Examples

Emperor, Jackass, Rockhopper

Falconiforms Examples

Northern Harrier, Steller's Sea Eagle, Osprey

Marine mammals obtain metabolic water?

From the breakdown of blubber; they do not drink seawater.

What adaptation helps marine mammals retain heat in their extremities during deep dives?

Countercurrent circulation in the extremities.

Highest density of hair mammal?

Sea otter.

Fur and blubber affect heat capacity in marine mammals?

They both increase heat capacity, helping animals retain warmth.

Bumps on humpback whales

Vestigial hair follicles.

How does increasing body size affect surface area-to-volume ratio in marine mammals?

Larger animals have a smaller surface area-to-volume ratio, which increases warmth.

Rounded body shape benefit marine mammals?

It further reduces the surface area-to-volume ratio, aiding in heat retention.

Function of blubber as a facing material?

It smooths out body contours, increasing hydrodynamics.

Myoglobin importance in the muscles of marine mammals

Stores oxygen for use during prolonged dives.

What is a synapomorphy of Family Phocidae (true seals)?

Hind limbs cannot rotate forward; they are belly walkers.

Do true seals have external ear flaps?

No external ear flap.

Where do most true seals give birth?

On pack ice (an ephemeral environment).

What is notable about the coat of true seal pups?

Thick white coat; some species molt in utero.

How do true seals swim?

Axial locomotion (sinuous movement).

Which pinniped is the most abundant and what does it eat?

Crabeater Seal; eats krill.

Which pinniped is considered the top predator in the Antarctic?

Leopard Seal.

Which pinniped is the most endangered?

Hawaiian Monk Seal.

What is a key feature of Family Otariidae (eared seals)?

Can sit up and walk quadrupedally; large front flippers.

How do eared seals swim?

Appendicular locomotion, using flippers.

What is a common feature of Family Balaenopteridae?

Multiple throat grooves; gulper feeders.

What is a characteristic of Family Balaenidae (right and bowhead whales)?

Slow-moving, skim feeders with very fine baleen.

What is notable about the North Atlantic Right Whale?

Most endangered, V-shaped blowhole, fewer than 300 left.

What is a synapomorphy of Suborder Odontoceti (toothed whales)?

One nasal blowhole (derived trait).

What is unique about the Sperm Whale’s blowhole and diving ability?

Asymmetrical blowhole; deepest diving (up to 3000 ft).

What is notable about Family Ziphiidae (beaked whales)?

Least known; deep divers; males have lower jaw tusks.

What is a characteristic of Family Delphinidae (dolphins)?

Crescent-shaped dorsal fin, conical teeth.

What is notable about the Harbor Porpoise (Family Phocoenidae)?

Smallest, no rostrum, flattened teeth.

What is a common trait of river dolphins (Families Platanistidae, Iniidae, Lipotidae, Pontoporiidae)?

Vestigial eyes, large melon, advanced echolocation.

What is a distinguishing feature of manatees (Family Trichechidae)?

Rounded tail.

What is the difference between Dugongidae and Trichechidae?

Dugongidae (dugong and Steller's sea cow) have fluked tails; Trichechidae (manatees) have rounded tails.

What is the only marine bear?

Polar Bear (Family Ursidae).

Which mustelid is adapted to marine life?

Sea otter (and marine otter) (Family Mustelidae).

How do most marine mammals live in water?

Most live at depth, not on shore or surface, balancing survival and reproduction with specialized body structure and function.

What is anatomy?

The structure of an organism.