1. Kingdom Animalia Phylum Chordata Class Mammalia
Marine Mammals
Kingdom Animalia
Phylum Chordata
Class Mammalia

2. Marine Mammal characteristics
All mammals share the following characteristics:
Hair
Nurse young (mammary gland)
Breathe air
Warm blooded
Live birth

3. 5 groups of marine mammals
Seals, Sea lions & Walruses
Sea otters
Polar bears
Whales and Dolphins
Manatees

4. Order Carnivora SubOrder Pinnepedia Characteristics:
Seals, Sea Lions, Walruses
Characteristics:
Pinneped means fin footed
Excellent swimmers
Thick layers of blubber to protect from cold
Make a barking sound
Nostrils can close for diving
Diet of mainly krill, crustacians, mollusks, fish, and squid

5. Photograph is property of the Riverhead Foundation
Seals
Seals (earless pinnipeds; family Phocidae) have 19 representative species
Rear flippers cannot be moved forward
No external ear flap
Claws (and fur) on flippers
Short, robust neck
Photograph is property of the Riverhead Foundation

6. Crabeater seal

7. Weddell seal

8. Leopard seal
Crabeater seal

9. Sea lions and fur seals vs. Seals
Sea lions and fur seals (Otariidae)
Seals (Phocidae)

10. Sea lions and fur seals
Sea lions and fur seals (eared pinnipeds; family Otariidae) have 15 representative species
Rotatable hind flippers
External ear flap
Long, flexible neck
No fur or claws on flippers

11. New Zealand fur seal

12. Pinnepeds
Family Otariidae - eared seals include sea lions and fur seals.
Can rotate both pectoral & pelvic fins to “walk” on land

13. Pinnepeds Family Phocidae - are true seals.
They have no visible ear flap.
No hind leg rotation
Front legs cannot support their weight
Because they must drag their back fins they are easy prey

14. Pinnepeds Family Odobenidae - walruses
found only in North Polar regions.
Use tusks to hoist themselves onto the ice and to dig for clams
Nearly became extinct due to humans killing them for their ivory tusks

15. Since the Marine Mammal Protection Act of 1972, hunting is illegal
Most pinnepeds (except walruses) are covered with dense, waterproof fur that was attractive to man.
Since the Marine Mammal Protection Act of 1972, hunting is illegal
As a result the shark has also experienced an increase in population because it’s food source is readily available.

16. Sea Otters Family Mustelidae Smallest of the marine mammals
Four functioning limbs
Have no blubber
Fur is dense and protects from cold
Otter pups can’t swim so they float or rest on the mother’s stomach.
Use tools such as rocks to break abalone
Use kelp to anchor themselves and young

17. Polar bears Family Ursidae Only recently added to marine mammal list
Extreme amounts of blubber
Fur is transparent
Skin is black
Feet look like snowshoes and are webbed
Cover their nose when hunting as not to be detected.

18. Polar bear Diet
Polar bears feed mainly on ringed and bearded seals. Also eat harp and hooded seals and scavenge on carcasses of beluga whales, walruses, narwhals, and bowhead whales.
On occasion, polar bears kill beluga whales and young walruses.
When other food is unavailable, polar bears will eat just about any animal they can get, including reindeer, small rodents, seabirds, waterfowl, fish, eggs, vegetation (including kelp), berries, and human garbage. (

19. Order Cetacea Whales, dolphins, and porpoises
Blue whale
Dolphin
Whales, dolphins, and porpoises
Grouped by their mouth structures
Family Mysteceti - baleen whales
Family Odontoceti - toothed whales

20. Family Mysteceti Possess baleen to strain plankton
Ex. right, humpback, blue
2 nostrils and 2 blow holes
Eat large amount of food that is low on the food chain
Dorsal fin is reduced in size or absent in larger whales
Right whale
Right Whale
Sperm whale

21. Family Odontoceti
Known as toothed whales because of their conical shaped teeth
Ex: sperm whale, orca, dolphins
2 nostril but only 1 blow hole
Porpoise

22. Cetaceans are protected by the Marine Mammal Protection Act of 1972
Cetaceans are protected by the Marine Mammal Protection Act of This act made whaling illegal in US coastal waters
Many are still being hunted under the guise of scientific research or are “by-catch” of the tuna fishery
The International Whaling Commission (I.W.C.) is a whalers organization that sets quotas based on catch size.
Problems with the IWC is that it is strictly voluntary and actual is set to protect the whaling industry not the whales.

23. Cetacean adaptations Swimming - use powerful tail flukes
Fluke markings are used like fingerprints for identification
Digestion - multi-compartmentalized stomachs “chew” food.
Even toothed whales don’t chew their food
Baleen whales eat krill and plankton
Toothed whales eat fish, penguins, seals…
Bowhead Right whale
Grey whale
Narwhal

24. Cetacean adaptations Circulation - 4 chambered heart
Blubber insulates against the cold.
Possess counter current heat exchange which keeps the whale from overheating.
Can transfer arteriole heat to surface tissues (flukes and fins)
Senses - vision is poor, uses echolocation to compensate

25. Cetacean adaptations
Whales have no vocal chords but make clicks and whines by vibrations in the blow hole
Sounds are emitted and amplified in the head through an oil filled cavity called a melon
Incoming vibrations are focused through the jaw and melon to the inner ear and the brain

26. Cetacean adaptations
Diving - lungs are emptied and filled quickly through blow hole on top of head
A trachea under the blow hole connects directly to lungs
Nasal passages close when relaxed to prevent water from entering the lungs
Oxygen is stored in muscles, ribs are collapsible to reduce internal air pockets
Whale strandings occur when they are ill to prevent drowning

27. Cetacean adaptations
Excretory - specialized kidneys allow whales to drink salt water. Urine has high salinity content
Reproduction - internal
Mating occurs in early summer, gestation lasts 7 months so the egg implantation is delayed 4 months so that the baby is born in the warm summer months
Most whales have 1 calf every 2-3 years
Whale milk is unusually high in fat content

28. Whale migrations Are timed to coincide with Weather Mating
Migrations of other fish
Births
Orca
Pilot whale
Humpback

29. Order Sirenia Manatees or Sea cows
Protected by the state of Florida since 1893
Protected by the Endangered Species Act of 1973
Protected by the Marine Mammal Protection Act of 1972
BUT ONLY AROUND 1200 STILL SURVIVE TODAY

30. 5 populations in the Order Sirenia
Family Dugongidae
Dugong
Found in Australia and Indonesia
Notched tail fluke
Stellar Sea Cow
Hunted to extinction within 27 years of its discovery in 1741
Family Trichechidae
West Indian manatee
Found from Florida to Brazil
Round paddle shaped tail
Amazonian manatee
West African manatee

31. Manatees
Manatees are related to the elephant through biochemistry and external features
Average 10’ in length and weighs ~ 1000lbs
Use blubber to keep warm
Herbivores that may eat 100 lbs of sea grass a day

32. Manatee characteristics
Their constant eating helps keep channels clear. Ironically this causes 50% of deaths due to careless boaters.
Manatees must surface to breathe
Whiskers (vibrissae) on snout used to rake in plants
Nurse young for a year. Mammary glands are located under flippers

33. Manatee characteristics
Live birth - gestation period of 13 months
Produce 1 calf ever 3-5 years
Large brain, poor vision
Warm blooded with 4 chambered heart
Stomach has compartments, it ruminates (chews its cud)
Breathes air - may dive for 20 minutes
Tail - horizontal paddle
Can produce high pitched whistle for communication

34. Manatee characteristics
Because they have no predators
they have no social structure,
not territorial,
herds don’t have a leader,
no permanent bonds are formed for mating