Marine Mammals

Question 1

List five physical characteristics unique to marine mammals

Answer 1

o streamlining of body shape
o limb modifications as flippers, disappearance of hind pair in some groups
o thermal regulation
o modified respiratory system - diving adaptations
o osmotic adaptations - impervious skin, efficient kidney, don’t drink much seawater

Question 2

State five characteristics that enhances marine mammals’ ability to thermoregulate.

Answer 2

 large size
 low surface to volume ratio
 thick skin
 blubber
 reduced peripheral circulation (blubber with few blood vessels) 
 higher metabolic rate

Question 3

Mysteceti (Baleen Whale) characteristics:

Answer 3

• Baleen plates present (lack teeth)
• Paired external nasal openings
• Small sternum, few ribs, can’t withstand beaching
• Communicates by series of moans, squeaks and screams

Question 4

Odontoceti (toothed whale) characteristics:

Answer 4

• Teeth present (lack baleen)
• Single external nasal opening
• Long and robust sternum, can withstand beaching
• Communicates via whistles and echolocation

Question 5

Odontoceti (toothed whale) communication:

Answer 5

• Whistles and echolocation (emitting rapid sounds, usually clicks, into blind areas and measuring the time these sounds take to travel to and from an object.

Question 6

What is the whale bone?

Answer 6

• Baleen
• Specialized, keratinized epithelial tissue
• arranged in a series of 100-400 plates
• Form a comb on each side of the mouth (in place of teeth)

Question 7

Describe the migration patterns of baleen whales

Answer 7

• Highly migratory
• High latitude feeding areas in summer (polar)
• Low latitude calving areas in winter (tropical)
• 3000 to 5000km each way
• Gray whales migrate 10000km each way

Question 8

How do baleen whales feed?

Answer 8

• Filter seawater
• To trap krill, copepods, amphipods, and small fish
• Use suction of tongue to palate to draw water in and opposite movement to force water out

Question 9

What species belong to the Rorqual family (5)?

Answer 9

Blue Whale
Fin Whale 
Humpback Whale 
Minke Whale
Sei Whale

Question 10

What are the distinguishing characteristics of the Rorqual family?

Answer 10

• Longitudinal grooves on throat
• Small pointed dorsal fin
• Largest whales on earth

Question 11

What species belong to the Grey Whale family?

Answer 11

• Grey whale

Question 12

What are the distinguishing characteristics of the Grey whale family (4)?

Answer 12

• Small dorsal hump
• 10-12 knobs on dorsal ridge
• Parasitic barnacles on their skin
• Unfused neck vertebrae

Question 13

How do Grey Whales feed and explain their migration pattern?

Answer 13

• Bottom feeders, suck up large amounts of sediment and filter out crustaceans
• Do not feed during breeding season
• November to early december begin migrating south to Baja
• February to early may they begin migrating northward again
• Migration is 10000km

Question 14

What species belong to the Balaenidae family?

Answer 14

• North Pacific Right Whale

Question 15

What are the distinguishing characteristics of right whales (4)?

Answer 15

• No dorsal fin
• No throat grooves
• Extremely long baleen plates
• Hugely arched jaw

Question 16

Why are they called ‘right’ whales?

Answer 16

• got its name from whalers who thought it was the “right”

whale to hunt, contains a huge amount of oil and baleen

Question 17

How do right whales feed?

Answer 17

• has black baleen plates up to 2.8 meters long, which it uses to catch copepods and krill near the surface. This feeding
  strategy is known as skimming.

Question 18

What are the distinguishing characteristics of Odontoceti (Toothed Whales) (5)?

Answer 18

• Single nasal opening
• Fat melon behind face?
• up to 220 teeth
• marked asymmetry of surrounding bones

Question 19

What families belong to the suborder Odontoceti (4)?

Answer 19

• Delphinidae (Dolphin family)
• Phocoenidae (Porpoise family)
• Ziphidae (Beaked whale family)
• ## Physteridae (Sperm whale family)

Question 20

Characteristics of dolphins

Answer 20

• Bulging forehead
• Teeth are unlobed
• Usually curved dorsal fins
• Sleek, streamlined bodies
• Distinct beak
• Deep tail notch and ridge on top of tail

Question 21

Characteristics of porpoises

Answer 21

• Lack a well-formed beak
• Blunt snout
• Stocky body
• Teeth are spade shaped

Question 22

Who are the “Ziphids”? What are their unique physical features?

Answer 22

Beaked whales:

• Long narrow snout
• Small and ovate pectoral fin
• Dorsal fin is small and sickle shaped
• Pair of grooves on the throat, form a V at the chin
• Few teeth (2-4)

Question 23

What are the unique features used to identify the sperm whale family (6)?

Answer 23

• Broad, flat rostrum
• Great depression on facial part of skull - accomodates spermaceti
• S-shaped blowhole located on left side of snout
• Numerous short grooves on throat
• Functional teeth only in lower jaw
• A left nasal passage for respiration, right one for hearing

Question 24

Breaching

Answer 24

• When a whale launches itself in the air head first and lands on water with a splash
• Not known why, could be courtship, dislogging parasites, fun etc.

Question 25

Spouting

Answer 25

• When a whale comes to surface to expel moist air from lungs and intake fresh air

Question 26

Podding

Answer 26

• Herding behavior during the breeding season and migration

Question 27

Describe porpoising

Answer 27

• Moving in and out of the water in a series of high speed leaps
• For momentum, speed, corraling fish, breathing

Question 28

Spy-hopping

Answer 28

• When cetaceans use their tails to hold themselves out of the water “tread water”
• For looking at surroundings

Question 29

Flipper slapping

Answer 29

• When cetaceans slap their flippers on the surface of water

Question 30

lobtailing

Answer 30

Same as flipper slapping but with their fluke. used for aggression or fun

Question 31

Compare and contrast resident and transient killer whales

Answer 31

Resident:

• Feed on fish

Transients:
- Feed on marine mammals

Question 32

Northern Pacific right whales natural history

Answer 32

• Slow swimming

- Extremely endangered