Marine Mammals

Classification: Class Mammalia

Order Pinnepedia Seals, sea lions, walrus

Order Carnivora Sea Otter, Polar Bear

Order Sirenia Manatees

Order Cetacea Suborder Mysticeti (Baleen Whales) Suborder Odontoceti (Toothed Whales)

Hawaiian Monk Seal

Feeding

Additional Video

1000 monk seals left

Critically endangered

Swimming Adaptations

Streamlined Body

Blowhole on top of their head

Thick blubber to keep warm

Diving Adaptations

Oxygen 90% oxygen is exchanged,

compared to 20% humans

Blood More blood Higher concentration of red

blood cells Muscles can store more

oxygen

Additional diving adaptations

Reduce oxygen consumption Bradycardia - Slow heart rate Peripheral Vasoconstriction -

Reduce blood flow to non-essential extremities

Prevent nitrogen dissolving in the blood Lungs collapse and flexible rib

cage

Sensory Adaptation - Echolocation

Most toothed whales

“nature’s sonar”

Emit sound waves, listen, analyze the time, determine how far the object is

Melon – focuses and directs sound waves

Jawbones (filled with fat) trasmits sound to inner ear

Behavioral Adaptations

Social groups

Communicate with vocalizations, postures, movements

Humpback Whale Songs

Human Interaction

Education

Research

Therapy

Help with fishing

BYCATCH in Nets 23% of total fisheries catch

around the world is discarded 20 million tons of unwanted

catch being thrown back Over 300,000 cetaceans killed

this way each year

Tuna Nets

Eastern Tropical Pacific

Spotted/Spinner dolphins are close to yellowfin tuna

Used to track

Use Purse Seine net

Encircle, traumatize, entangle, kill

Humpback Whale

6,000 humpbacks in the N. Pacific

Leave Alaska in the Fall

Breed in Hawaii

Leave in February/March to feed in Alaska in the summer