quiz 4

Question 1

What are the characteristics that define a mammal

Answer 1

• hair or fur (reduced in some marine mammals)
• endothermic
• mammary glands
• uterine gestation
• lungs
• 4 chambered hearts

Question 2

What do marine mammals use blubber for

Answer 2

insulation; warmth, food reserves

Question 3

what do sea otters eat

Answer 3

mollusks, crustaceans, and echinoderms (sea starts and urchins)

Question 4

why is climate change/sea ice melting an issue for marine mammals like polar bears?

Answer 4

• polar bears are forced to search on land
• many pinnipeds breed on pack ice
• many species use ice as a refuge when hunting
• walruses are especially vulnerable because they cannot stay in deep water for long
• food resources are changing

Question 5

What aspects of marine mammal behavior and reproduction makes them susceptible to human influence?

Question 6

What is convergent evolution?

Answer 6

the process by which unrelated species evolve similar physical characteristics because they have similar lifestyles

Question 7

how do baleen whales use their baleen to feed

Answer 7

rows of flexible plates hang down from the upper jaws; the inner edge of each plate consists of hair-like bristles that overlap and form a dense mat

Question 8

what is baleen made of

Answer 8

keratin

Question 9

why were whales hunted historically

Answer 9

commercially hunted for their meat and blubber which was processed into fuel, soaps, and other products

Question 10

how do toothed whales use their teeth

Answer 10

only to catch and hold prey, not to chew it

Question 11

how many blowholes do toothed whales have

Answer 11

just one

Question 12

differences between dolphins and porpoises

Answer 12

porpoises - blunt nosed, flattened teeth
dolphins - distinctive snout, conical teeth

Question 13

how do toothed whales use echolocation

Answer 13

emit sound waves, listen for the echoes reflected back from surrounding objects, brain analyzes the echoes
(the time it takes the echoes to return tells the animal how far away the object is)

Question 14

how to toothed whales use vocalizations

Answer 14

to communicate to feed, reproduce, or play
sounds can be pod-specific, different sounds associated with different moods

Question 15

what is cooperative feeding

Answer 15

when two or more individuals effectively capture more and/or bigger prey

Question 16

examples of how whales engage in cooperative feeding

Answer 16

humpback whales - bubble net feeding

Question 17

how do marine reptiles breathe and where do they reproduce

Answer 17

breathe air using lungs and most reproduce on land

Question 18

what are some threats to cetaceans

Answer 18

• noise pollution
• entanglements and drownings (fishing gear)
• boat strikes

Question 19

why can’t marine reptiles live in the cold?

Answer 19

reptiles are cold-blooded, so limited to warmer temp regions

Question 20

how do reptiles deal with ridding themselves of excess salt

Answer 20

osmoregulation, special salt glands

Question 21

in what ways are sea turtles adapted to living in the sea

Answer 21

They developed Paddle-shaped forelimbs, wing-like swimming, non-retractile head and limbs, completely roofed skull, backbone fused to shell (except leatherback), streamlined body, good sense of smell, good vision, salt glands near eyes, slow metabolic rate, long lifespan, return to land to lay eggs

Question 22

what is the sea turtle nesting process

Answer 22

migrate to home beach, dig hole, lay eggs, eggs hatch, turtles find
ocean and hope to survive

Question 23

How is sex determined in sea turtles

Answer 23

The temperature in which they are burrowed in, Cold and wet= male, hot and dry = female

Question 24

why are sea turtles threatened by climate change

Question 25

Why are floating plastic and balloons so harmful to sea turtles?

Answer 25

esophagus of a sea turtle has barbs that face the stomach so cannot regurgitate things once swallowed

Question 26

What are the challenges a sea turtle faces to survive from egg to reproductive age?

Answer 26

Has to hatch, then has to survive the journey from the burrow to the seashore, then has to survive and avoid all the predators in the sea. Survive the currents and harsh weather. And human pressure too. Pollution, boats ect.

Question 27

What adaptations have marine reptiles evolved for living in water?

Question 28

Why do sea turtles migrate such long distances?

Answer 28

For more better water conditions, more food, better breeding opportunities

Question 29

what are Poikilotherms?

Answer 29

cold blooded animals

Question 30

What is natal homing for sea turtles?

Answer 30

when they return to the same beach they were born on to lay eggs

Question 31

Seabirds are usually monogamous, why is this an advantage?

Answer 31

it helps with heavy parental investment, defense of eggs, protect young, work together, do not lay eggs every year

Question 32

What are some of the physical adaptations that marine birds have that enable them to succeed in the marine environment

Answer 32

Webbed feet, streamlined body, hard-shelled eggs, waterproof feathers, good eyesight and sense of smell, dense bones, increased red blood cells, salt-excreting glands.

Question 33

How do marine birds feed?

Answer 33

Surface feeding, pursuit diving, plunge diving, adapted beaks.

Question 34

Why are marine birds eating plastic?

Answer 34

it can resemble prey and is often mistaken for food.

Question 35

what is overfishing, and why is it a problem

Answer 35

is a depletion of stock below sustainable levels for replenishment.

Question 36

What is the Great Pacific Garbage Patch?

Answer 36

Collection of marine debris in the North Pacific Ocean

Question 37

why is commercial fishing now a problem vs historical/subsistence fishing methods

Question 38

What life history/behavioral aspects make a fish particularly vulnerable to being overfished?

Answer 38

Maturity time, reproductive capacity, and behavior.

Question 39

What are some of the challenges of managing fisheries?

Answer 39

Biological, economic, and socio- aspects.

Question 40

order pinnipedia

Answer 40

seals, sea lions, walruses

Question 41

order cetacea

Answer 41

whales, dolphins and porpoises

Question 42

order carnivora

Answer 42

sea otters, polar bears

Question 43

order sirenia

Answer 43

dugongs and manatees

Question 44

how do seals manage to dive for so long?

Answer 44

- slow heart rate to below resting - constrict blood vessels to keep blood near major organs - have 2x as much blood as humans - use hemoglobin in blood an myoglobin in muscle to carry oxygen

Question 45

where do walruses live

Answer 45

strictly arctic

Question 46

what do walruses eat

Answer 46

benthic feeder; feeds primarily on clams

Question 47

what do seals and sea lions eat

Answer 47

predators, feed mainly on fish and squid, crabs, penguins

Question 48

where are sea otters found

Answer 48

only in the pacific ocean

Question 49

what do sirenians eat

Answer 49

herbivorous; feed on seagrass and algae

Question 50

what threatens sirenians

Answer 50

motor boat collisions, harmful algal blooms, pollution, and severe winters

Question 51

what are the two groups of cetaceans

Answer 51

toothed whales - dolphins and porpoises baleen whales- toothless. filter feeding whales

Question 52

how are baleen whales characterized

Answer 52

baleen and double blowholes

Question 53

What is a trait that many marine animals have that shows convergent evolution? Ex. Shark vs. Penguin

Answer 53

streamlined body

Question 54

how do marine reptiles breathe and reproduce

Answer 54

using lungs and on land

Question 55

What is another reason fish are overharvested?

Answer 55

Fishing gear, many fish get caught accidently due to to poor fishing gear designs.

Question 56

What are Biological considerations of fish that contribute to overharvesting?

Answer 56

Age to maturity, growth rate, size at maturity, spawning/reproductive style, Spawning location, Size/ age structure of the population, independence of stock

Question 57

What is the Maximum Economic Yield (MEY)?

Answer 57

the sustainable catch or effort level for a commercial fishery that allows net economic returns to be maximized

Question 58

What is the Maximum Sustainable Yield (MSY)?

Answer 58

defined as the maximum catch (in numbers or mass) that can be removed from a population over an indefinite period

Question 59

What is bottom trawling? What is the issue?

Answer 59

Bottom trawling is when a huge net dropped onto the sea floor and dragged several miles. This catches many unwanted fish, and often scrapes up the sea floor in the process.

Question 60

What is purse-seine fishing?

Answer 60

fishing that is used to catch surface dwelling species such as Tuna, Mackerel, Anchovies, and Hearing, which tend to feed in schools near the surface or in shallow areas, this technique requires a big net to swoop up all the fish. This often leads to a lot of bycatch.

Question 61

What is longlining?

Answer 61

A type of commercial fishing that uses baited hooks on shorter lines connected to a long line held up with floats. This often has a lot of bycatch

Question 62

What are Gillnets?

Answer 62

A type of woven mesh which gets dropped in the water to catch fish. This woven mesh is strong and is impossible to escape from. The holes in the mesh are big enough to swim though, but small enough to get stuck halfway. Fish cannot swim out, because the net gets caught on their dorsal fin.