Transcript Marine Mammals

Marine Mammals
Mammals have a 4
chambered heart.
 Mammals are warmblooded.
 They have hair/fur.
 Have mammary
glands.
 Give birth to live
young.

Pinnepeds
• Ex: Seals, Walruses, Sea Lions.
• Marine mammals that have flippers and
blubber
• Need to breed on land.
• Live in cold water, and have a thick layer of
blubber to keep them warm.
• Mostly carnivores and feed on squid and fish.
• Streamlined bodies and are excellent
swimmers.
Seals
• Seals have rear flippers.
• They move forward by pulling
themselves along the ground.
• Seals do not have ear flaps.
• 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.
Walruses
• Have large protruding
tusks for digging up
mollusks.
• They have stiff
whiskers for feeling
around on the ocean
floor.
• They are the largest
Pinneped, weighing up
to 2700 lbs!
Sea Otters
• 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 eat mostly shell fish and spend
most of the day maintaining their fur.
Polar Bears
• They are semi aquatic, so 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
• These animals spend their entire lives in the
water.
• They are streamlined, and look fish-like.
• They breathe air through lungs and have
nostrils on the tops of their heads called a
blowhole (some single, some double).
• This is the largest group of Marine Mammals,
consisting of Whales , Dolphins, and
Porpoises.
• There are more than 90 species divided into
two groups: toothed Whales (which includes
Dolphins and Porpoises), and toothless
Whales which have a Baleen.
Baleen Whales
• 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.
Toothed Whales
• Teeth are adapted for a diet of squid, fish, and
other prey and are used to catch and hold prey,
not to chew it.
• There are 80 species of toothed Whales.
• The largest of the toothed Whales is the Sperm
Whale, made famous by the novel “Moby Dick”.
Dolphins
• Highly intelligent creatures, that can be easily
trained, are playful, and have been known to
“escort” ships.
• It is common for dolphins to get caught in fishing
nets meant for other species.
Porpoises
• Porpoises are divided in to six species.
• Shorter than the average dolphin, more shy,
and they don’t tend to live as long.
• Have flattened, spade-shaped teeth.
Dall's Porpoise
Harbour Porpoise
Narwhals
• Related to bottlenose dolphins, belugas, harbor
porpoises, and orcas.
• Found in Arctic coastal waters and rivers.
• In males, a prominent tooth grows right through the
upper lip into a sword like, spiral tusk up to 2.7 meters
long.
• Some believe it is used to impress females or to battle
rival suitors.
• They travel in groups and feed on fish, shrimp, squid,
and other aquatic fare.
• Inuit people hunt the narwhal for their long tusks and
their skin, an important source of vitamin C
Belugas
• Belugas are also called white whales.
• Smallish (4 to 6.1 meters).
• They have rounded foreheads and no dorsal
fin.
• Common in the Arctic Ocean's coastal waters
• Feed on fish, crustaceans, and worms.
• Related to the narwhal.
Communication
• One way Cetaceans communicate
is through Echolocation (nature’s
version of sonar).
• They release tiny bubbles through
their blowholes and make clicking
sounds to communicate with each
other, determine distances, and
warn others about danger.
• The Melon (fatty structure on the
top of their heads) focuses and
directs these sound waves.
Breaching
• When Whales leap in the air and loudly
crash on the surface of the water.
• This can be a warning signal, a way to get
rid of external parasites, a fun activity, or a
way of scanning the surface.