I. Marine Mammals

D. Cetacea1. Mysticeti (Baleen Whales) – 15 species

• Includes largest animal ever on earth• Blue whale – To 33.5 m long, 100+ tons

• Baleen plates attached to upper jaws• Made of keratin (same protein as hair, fingernails)• Squeeze water through baleen and lick off

retained food (usually organisms)• Primarily feed on zooplankton• Three families:

• Balaenidae (right and bowhead whales)• Balaenopteridae (rorquals)• Eschrichtidae (gray whale)

Right whaleFig. 12-15

Fig. 12-14

Blue

I. Marine Mammals

D. Cetacea1. Mysticeti (Baleen Whales) – 15 species

• Includes largest animal ever on earth• Blue whale – To 33.5 m long, 100+ tons

• Baleen plates attached to upper jaws• Made of keratin (same protein as hair, fingernails)• Squeeze water through baleen and lick off

retained food (usually organisms)• Primarily feed on zooplankton• Three families:

• Balaenidae (right and bowhead whales)• Balaenopteridae (rorquals)• Eschrichtidae (gray whale)

Right whaleFig. 12-15

I. Marine Mammals

D. Cetacea1. Mysticeti (Baleen Whales) – 15 species

a. Balaenidae – 5 species• Bowhead, N Atlantic, N Pacific, Southern, Pygmy Right• No: dorsal fin, throat grooves• Feed continuously while swimming• Long, fine baleen

b. Balaenopteridae – 9 species• Bryde’s, Blue, Eden’s, Fin, Humpback, Antarctic Minke,

Common Minke, Omura’s, Sei• Feed by gulping schools of fish or krill• Ventral grooves expand during “gulp”• Large blue whales may enclose up to 17,500 gallons

(70 tons) of water in one gulp• Blue whales eat 3,000-5,000 kg of food each day!• Short baleen, small dorsal fin, ventral grooves

c. Eschrichtidae – 1 species• Gray• Feed by scooping sediments & organisms from sea floor• Short coarse baleen, no dorsal fin, 2-5 ventral grooves

Right

Humpback

Blue

Gray

North Atlantic Right Whale

Fig. 12-14

Southern Right

I. Marine Mammals

D. Cetacea1. Mysticeti (Baleen Whales) – 15 species

a. Balaenidae – 5 species• Bowhead, N Atlantic, N Pacific, Southern, Pygmy Right• No dorsal fin, throat grooves• Feed continuously while swimming• Long, fine baleen, no dorsal fin, no ventral grooves

b. Balaenopteridae – 9 species• Bryde’s, Blue, Eden’s, Fin, Humpback, Antarctic Minke,

Common Minke, Omura’s, Sei• Feed by gulping schools of fish or krill• Ventral grooves expand during “gulp”• Large blue whales may enclose up to 17,500 gallons

(70 tons) of water in one gulp• Blue whales eat 3,000-5,000 kg of food each day!• Short baleen, small dorsal fin, ventral grooves

c. Eschrichtidae – 1 species• Gray• Feed by scooping sediments & organisms from sea floor• Short coarse baleen, no dorsal fin, 2-5 ventral grooves

Right

Humpback

Blue

Gray

Fig. 12-14

Humpback

Fig. 12-16

I. Marine Mammals

D. Cetacea1. Mysticeti (Baleen Whales) – 15 species

a. Balaenidae – 5 species• Bowhead, N Atlantic, N Pacific, Southern, Pygmy Right• No dorsal fin, throat grooves• Feed continuously while swimming• Long, fine baleen, no dorsal fin, no ventral grooves

b. Balaenopteridae – 9 species• Bryde’s, Blue, Eden’s, Fin, Humpback, Antarctic Minke,

Common Minke, Omura’s, Sei• Feed by gulping schools of fish or krill• Ventral grooves expand during “gulp”• Large blue whales may enclose up to 17,500 gallons

(70 tons) of water in one gulp• Blue whales eat 3,000-5,000 kg of food each day!• Short baleen, small dorsal fin, ventral grooves

c. Eschrichtidae – 1 species• Gray• Feed by scooping sediments & organisms from sea floor• Short coarse baleen, no dorsal fin, 2-5 ventral grooves

Right

Humpback

Blue

Gray

Fig. 12-19

I. Marine Mammals

D. Cetacea2. Odontoceti (Toothed Whales) – 74 species

a. Sperm whales – 3 species• Sperm, Dwarf, Pygmy• Bulbous head contains spermaceti (waxy substance)

that may function in buoyancy and sound generation• Sperm whales can dive to 3000 m and stay under water

for up to two hours!• Feed on fishes and squids, esp. giant squids• Produce ambergris, undigested material in stomach

b. Toothed whales – 28 species• Beaked, Beluga, False Killer, Narwhal, Orca, Pilot• Most common in cold water

c. Dolphins & Porpoises – 43 species• Distinctive beak• Travel in pods

Fig. 12-20

Ambergris

I. Marine Mammals

D. Cetacea2. Odontoceti (Toothed Whales) – 74 species

a. Sperm whales – 3 species• Sperm, Dwarf, Pygmy• Bulbous head contains spermaceti (waxy substance)

that may function in buoyancy and sound generation• Sperm whales can dive to 3000 m and stay under water

for up to two hours!• Feed on fishes and squids, esp. giant squids• Produce ambergris, undigested material in stomach

b. Toothed whales – 28 species• Beaked, Beluga, False Killer, Narwhal, Orca, Pilot• Most common in cold water

c. Dolphins & Porpoises – 43 species• Distinctive beak• Travel in pods

Pilot

Beluga Beaked

False Killer

Narwhal

I. Marine Mammals

D. Cetacea2. Odontoceti (Toothed Whales) – 74 species

a. Sperm whales – 3 species• Sperm, Dwarf, Pygmy• Bulbous head contains spermaceti (waxy substance)

that may function in buoyancy and sound generation• Sperm whales can dive to 3000 m and stay under water

for up to two hours!• Feed on fishes and squids, esp. giant squids• Produce ambergris, undigested material in stomach

b. Toothed whales – 28 species• Beaked, Beluga, False Killer, Narwhal, Orca, Pilot• Most common in cold water

c. Dolphins & Porpoises – 43 species• Distinctive beak• Travel in pods

Harbor Porpoise

Bottlenose Dolphin

Dall’s Porpoise

Pacific White-Sided Dolphin

SpectacledPorpoise

Dusky Dolphin

I. Marine Mammals

D. Cetacea• Echolocation

• Common in dolphins, porpoises, toothed whales• May occur in some baleen whales and pinnipeds

• Sounds generally consist of sharp clicks• Low-frequency clicks can travel long distances

• Functions• Detect objects (orientation clicks)• Characterize objects (discrimination clicks)• Sonic hunting

• Mechanism• Air forced through air sacs and focused through

melon• Sperm whales may use spermaceti organ

• Sound received through lower jaw

Fig. 12-24

Dolphins WhalesDolphins Whales