Chapter 13. The Nekton: Swimmers of the Sea

Which of the following marine birds best fits this description: strong fliers, found mainly in coastal areas, and have a large beak with a pouch for catching fish?

Pelicans

Which of the following are examples of marine birds? (Mark all that apply.)

Terns Pelicans Puffins

Swimming marine invertebrates include which of the following? (Mark all that apply.)

• Squid • Large shrimp

Nekton are oceanic organisms that are _____. (Mark all that apply.)

• capable of directing their movement through the neritic and pelagic environments • either invertebrates or vertebrates

About ____% of bird species are considered marine.

3

How many bird species are marine?

3%

In order for an organism to be classified as "marine," it must spend at least _____ percent of its life in the marine environment.

50

Which of the following traits are common among sea snakes?

Ability to close the nostrils Flattened tail Extremely poisonous

Which of the following are true of marine mammals? (Mark all that apply.)

All marine mammals are warm-blooded. Some marine mammals return to land to give birth. All marine mammals have hair at some point during their development.

Some whales use strainers of ____ to catch small prey such as krill, whereas others have ____ to catch prey such as tuna.

Baleen teeth

Which of the following characteristics are true about bony fish? (Select all that apply.)

Bony fish can hover in the water and swim backward. Most bony fish possess a swim bladder to maintain buoyancy. All bony fish possess gills.

Which of the following are considered sea cows? (Mark all that apply.)

Dugongs Manatees

is the use of sound to picture the environment, and it is used by dolphins.

Echolocation

Which of the following characteristic is true regarding jawless fish?

Evolutionarily, they are the most primitive of fishes.

Which of the following are true about fish distribution in the ocean? (Mark all that apply.)

Fish populations are concentrated in shallow coastal areas. Fish can be found at all depths in the ocean. Fish can be found in all of the world's oceans.

Which of the following characteristics are found in sea turtles but not land turtles?

Front limbs flattened into paddles

Which of the following are examples of marine reptiles? (Mark all that apply.)

Gavial Green turtle Marine iguana

Match the marine mammal species with its correct form of communication.

Humpback whales ↔ Long songs Female gray whales ↔ Series of grunts Weddell seals ↔ Squeaks

Why do seabirds breed in dense colonies (as large as a million or more birds) on islands, cliffs, or headlands?

It provides them with protection from land predators.

Which of the following are common adaptations for deep-sea bony fish species? (Mark all that apply.)

Large, needlelike teeth Light organs on their bodies Hinged jaws

Songs that last up to thirty minutes and that change each breeding season are produced by which marine mammals?

Male humpback whales

In 1972, the U.S. Congress established the ______, which includes a ban on the hunting and killing of all marine mammals and of the importation of any marine mammal or their products.

Marine Mammal Protection Act

Which of the following marine reptiles is a modern lizard, found in the Galápagos Islands, and has a flattened tail for swimming?

Marine iguana

Match the whale suborder to its correct physical characteristic.

Odonticetes ↔ Possess teeth and jaws Mysticetes ↔ Have mouths fitted with strainers of baleen

____ behavior has evolved independently in the majority of fish species because it may confuse predators, enhance foraging, and save energy by swimming together.

Schooling

____ turtles cannot retract their heads into their shells, but ____

Sea Land

Which of the following characteristics are true about sharks? (Mark all that apply.)

Sharkskin is extremely abrasive, like sandpaper. Receptors along the shark's sides are sensitive to touch, vibration, currents, sound, and pressure. Sharks have an acute sense of smell.

Match the whale species to its correct suborder.

Sperm whale ↔ Odontocetes Blue whale ↔ Mysticetes

he swimming marine invertebrate shown in the image is a

Squid

Which of the following statements are true regarding seals and sea lions? (Mark all that apply.)

They both have four characteristic flippers. They both have hair and blubber. They both need to rest and breed on land.

Which of the following characteristics of polar bears are true? (Mark all that apply.)

They feed primarily on ringed seals. They have more problems with overheating than getting too cold. They are strong swimmers.

Which of the following statements are true regarding walruses? (Mark all that apply.)

They have no external ears. Both males and females have tusks.

How can a bird or a reptile be considered a "marine" animal?

They spend at least 50% of their lives in the marine environment.

Which seabird characteristics enable them to swim or dive in the ocean? (Mark all that apply.)

Webbed feet Ability to pull in their feathers close to their bodies to squeeze out trapped air Feathers that are waterproofed by an oily secretion called preen

The Marine Mammal Protection Act includes ______. (Mark all that apply.)

a ban on the importing of any marine mammals or their products a ban on the hunting and killing of marine mammals

The melon of a dolphin ______.

acts like a lens to concentrate clicking sounds into a beam

Unlike most fishes, most sharks ______.

bear live young

Osteichthyes is the name of the class of fish also referred to as ____ fish

bony

Whales belong to a group of mammals called _____

cetaceans

Fish are concentrated in the oceans' upwelling areas, shallow coastal areas, and

estuaries

To adapt to a scarce food supply in the deep sea, some species of fish have ______. (Mark all that apply.)

expandable guts teeth that point inward to lessen the potential for prey to escape hinged jaws

Marine snakes have _____ tails, but terrestrial snakes do not.

flattened

Marine mammals are ______, which means they can maintain a near-constant body temperature, frequently well above the mean water temperature in which they live.

homeotherms

The whales in the image possesses baleen and are most likely ______ whales.

humpback

Sea otters live ______, and they eat ______.

in kelp beds; sea urchins

Walruses live ____.

in the waters on both coasts of the Bering and Chukchi Seas

____ fish have a sucking mouth with teeth or dental plates and lack paired fins and stomachs.

jawless

One example of a toothed whale is the ____ whale featured in the image

killer or orca

The order Sirenia includes two members known as sea cows, the ____ and the ____.

manatees dugongs

Schooling has evolved independently in the majority of fish species because it ______. (Mark all that apply.)

may confuse predators saves energy reduces individual encounters with predators may enhance foraging success

The bulbous, fatty, rounded structure on the forehead of a dolphin is called the ______.

melon

____ include approximately 5000 species of invertebrates and vertebrates capable of swimming freely through the neritic and pelagic environments.

nekton

Seabirds get protection from predation during breeding season by _____.

nesting on islands, cliffs, or headlands

Polar bears are found in ___.

northern hemisphere

The purpose of whaling in the 1700s and 1800s was to hunt whales for their and .

oil baleen

Whaling was conducted in the 1700s and 1800s in order to get ______ from whales. (Mark all that apply.)

oil baleen

Seals and sea lions belong to the ____, or "feather-footed" animals, named because of their four characteristic flippers.

pinnipeds

Seabirds may drink seawater, so to remove excess salt from their bodies, _____.

salt becomes concentrated by a gland over their eyes and is removed by either dripping out or being blown through their nasal passages

Echolocation is ______.

the ability to use sound to picture the environment

Sea otters are ______. (Mark all that apply.)

the smallest marine mammals considered keystone predators in kelp forests