Transcript Marine Mammals

Marine Mammals
What is a Mammal?
• Mammals have a 4
chambered heart.
• Mammals are warmblooded.
• They have hair/fur.
• Have mammary
glands.
• Give birth to live
young.
Pinnepeds
• Pinnepeds are marine mammals that have
flippers and blubber, that need to breed on
land.
• Seals, Walruses, and Sea Lions all belong to
this Order.
• Pinnepeds live in cold water, they have a
thick layer of blubber to keep them warm.
• They are mostly carnivores and feed on squid
and fish.
• They have streamlined bodies and are
excellent swimmers.
• Seals are the largest group of pinnepeds.
Seals
• Seals have rear flippers.
• They move forward by pulling
themselves along the ground.
• Seals do not have ear flaps.
• They are hunted for their fur
and are protected by the
Marine Mammal Protection
Act of 1972.
• There are approximately 19
species of Seals.
Sea Lions
• Are also called Eared Seals,
because they have external ear
flaps.
• They can move their rear flippers
forward to walk.
• They are graceful and agile
swimmers.
• These are the “guys” that you see
at Marine World or an Aquarium
doing neat tricks and they also
work for the US Navy!
• At one time they were hunted for
their fur, but are now protected by
the MMPA of 1972.
Walruses
• Have large protruding
tusks for digging up
mollusks. They love to
eat clams!
• They have stiff
whiskers for feeling
around on the ocean
floor.
• They are the largest
Pinneped, weighing up
to 2700 lbs!
Sea Otters
• Are members of the Order Carnivora.
• They are the smallest Marine Mammal, weighing
60-80 lbs.
• They lack a layer of blubber, and make up for it by
trapping air in their dense fur.
• They were slaughtered to the brink of extinction
for their beautiful fur, but became protected by an
international agreement in 1911.
• They are playful, and intelligent.
• They eat mostly shell fish and spend most of the
day maintaining their fur.
Polar Bears
• Is the second member of the order
Carnivora that is a Marine Mammal.
• They are semi aquatic, and inhabit both
the land and the sea.
• They feed primarily on seals.
• They have recently been put on the
endangered species list because of loss
of habitat due to global warming.
Cetaceans
• This is the largest group of Marine Mammals,
consisting of Whales , Dolphins, and
Porpoises.
• These, of all the Marine Mammals, have
made the most complete transition to aquatic
life.
• These animals spend their entire lives in the
water.
• They are streamlined, and look remarkably
fish-like.
• They breathe air through lungs and have
nostrils on the tops of their heads called a
blowhole (some single, some double).
• There are more than 90 species of
Cetaceans.
• They are divided into two groups: toothed
Whales (which includes Dolphins and
Porpoises), and toothless Whales which have
a Baleen.
• Instead of teeth, Baleen Whales have rows of
flexible, fibrous plates, that hang from the
upper jaws (called a Baleen). These are
used to filter out plankton and tiny organisms
from the water.
• Baleen Whales are the largest animals to
ever have lived on this planet.
• There are 13 species of Baleen Whales, the
Blue Whale being the largest at up to 110 ft.
long, and up to 200 tons.
• The remaining 80 species of Cetaceans are
toothed Whales.
• Their teeth are adapted for a diet of squid,
fish, and other prey.
• Teeth are used to catch and hold prey, not to
chew it.
• The largest of the toothed Whales is the
Sperm Whale, made famous by the novel
“Moby Dick”.
• Killer Whales, or Orcas, are beautiful black
and white Whales that are predators, eating
seal, penguins, sea otters, and fish.
• They are more common in cold water, but are
found round the world.
• Dolphins are highly intelligent creatures, and
can be easily trained..
• They are very playful, and have been known
to “escort” ships for miles at a time.
• Porpoises are really blunt nosed smaller
Whales.
• Dolphins, Porpoises, and Whales travel in
groups called Pods.
• They are protected by the MMPA of 1972, but
are still hunted.
• The Japanese, and Norwegian fishing
Industries have been illegally whaling under
false pretenses ( scientific whaling).
• It is common for Cetaceans to get caught in
fishing nets meant for other species.
Communication
• One way Cetaceans communicate is through
Echolocation.
• They release tiny bubbles through their
blowholes and make clicking sounds to
communicate with each other and determine
distances, and warn others about danger.
• This is natures version of Sonar.
• The Melon (fatty structure on the top of their
heads) focuses and directs these sound
waves.
• Cetaceans produce a rich variety of sounds
tha are associated with different moods,
sexual signaling, feeding, alarms……
Breaching
• When Whales leap in the air and loudly
crash on the surface of the water.
• This can be a warning signal, getting rid
of external parasites, fun, or a way of
scanning the surface.
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