Marine Mammals. Classification: Class Mammalia Order Pinnepedia Seals, sea lions, walrus Order...
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Transcript of Marine Mammals. Classification: Class Mammalia Order Pinnepedia Seals, sea lions, walrus Order...
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)
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
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