1. Marine Mammals

3. Marine mammal
A marine mammal is a mammal who lives in a  marine environment (or in some cases an aquatic environment) and obtains all or most of its food there.

4. What does it mean to be a mammal?
They have lungs and breath air.
They are warm blooded and maintain a constant body temperature. 
Most give birth to live young. One primitive mammal group, the Monotremes (which includes the duckbill platypus and the echidna) lays eggs.
They produce milk and nurse their young.
They have hair at some point in their lives. 

5. Name some marine mammals:

6. For animals that live in the seas and oceans, those that meet all five criteria certainly include seals, sea lions, walruses, sea otters, polar bears and manatees.  
But what about dolphins, whales and porpoises?  Hair?
Yes, very early in life these animals posses hair around their mouths which are usually lost soon after birth.

7. There four general types of marine mammals
Cetaceans - whales, dolphins and porpoises
Pinnipeds - seals, sea lions and walruses
Sirenians - dugongs and manatees
Carnivores - sea otters and polar bears

8. Cetaceans - whales, dolphins and porpoises

10. Pinnipeds - seals, sea lions and walruses

11. Sirenians - dugongs and manatees
While manatees have a paddle-shaped tail. the dugongs have a tail that is pointed on the ends, very much like a whale's.

13. Whales and Dolphins
Orca (Killer whale)
Bottlenose dolphin

14. Carnivores - sea otters and polar bears

15. 1. CETACEA
Whales and Dolphins come from the same family, CETACEA (sey-tay-sha)
There are about 80 kinds of whales and dolphins that we know of right now.

16. What do whales and dolphins have in common?
They both breath from a blowhole located at the top of their head.
Minke whale

17. Whales and dolphins are mammals
They are mammals because they have:
lungs not gills
they have hair not scales
they also give live birth and don't lay eggs.

18. There are two major groups of whale:
1.Toothed whales (suborder Odontoceti)
2. Baleen whales
(toothless)
(suborder Mysticeti).
orca

19. Toothed Whales Toothed whales include several families
the beaked and bottlenose whales (family Ziphiidae)
the sperm whale (family Physeteridae);
Point of interest:
The white whale Moby-Dick, of Herman Melville's novel, was not a beluga but an albino sperm whale

20. Bottlenose whale

21. Beaked whale

22. Sperm Whales have the largest "nose" in the animal kingdom
Sperm Whales have the largest "nose" in the animal kingdom. The nose contains an oil filled case which scientists believe the animal uses to produce and focus sound

23. c) the beluga, or white whale, and the narwhal (family Monodontidae),

24. beluga

25. beluga

28. d) small polar whales with no dorsal fin and only a few teeth; the river dolphins (family Platanispidae),
River dolphins inhabit muddy rivers of India and South America;

29. River dolphin

30. e) ocean dolphins and porpoises (there are several families), the killer whale and pilot whale are types of dolphins.

33. Pilot whales
Killer whale

34. Echolocation
Many species use echolocation (sonar) for underwater navigation and hunting. They have a single blowhole and a wide throat to accommodate large prey.

35. Toothless Whales There are three families of baleen whales
The right whale family (Balaenidae), including the bowhead, or Greenland whale;

38. We can now use radio telemetry to find out where whales go…

39. The North Atlantic Right whale’s north-south migration between calving and feeding grounds hugs the coast, setting up dangerous intersections with intensive east-west ship traffic through busy East Coast ports. Ship collisions are a major factor causing the right whale’s population decline.

40. 2) the gray whale family (Eschrichtidae), with a single species (Eschrichtius robustus) found in the North Pacific Ocean;

43. 3) the rorqual family (Balaenopteridae)
This group includes:
humpback whale
sei whale
minke whale
Bryde's whale
the fin whale (or common rorqual)
the blue whale (which can grow to a length of 100 ft (30 m) and a weight of 150 tons)

44. humpback

45. Dwark minke whale

46. humpback

47. Sei whale

48. Fin whale

49. Bowhead whale

50. Baleen Plates

51. Baleen Plates Baleen whales use their mouth as a giant strainer.
The upper jaw is lined with bony plates called baleen that hang vertically like vertical blinds.
The spaces between the plates are small allowing water to pass through, but not the food.
The whale swims through the schools of fish with its mouth open taking in both fish and water. The throat pleats expand to make more room.
Then the whale closes its mouth and pushes the water out through the baleen plates trapping the fish inside to be swallowed.

52. Toothless whales are large species, usually over 33 ft (10 m) long.
They are filter feeders, living on shrimplike krill, plankton, and small fish.
They lack teeth but have brushlike sheets of a horny material called baleen, or whalebone, edging the roof of the mouth

53. Blue Whales are the largest to have ever lived on the planet at a recorded length of more than 110 feet and a weight of around 190 tons

55. Pinnipeds “winged feet"
aquatic mammals that use flippers for movement on land and in the water
they are carnivores
All pinnipeds must come ashore to breed, give birth, and nurse their young

56. Three families of living pinnipeds are recognized:
1. Earless seals or true seals (Phocidae)
2. Eared or fur seals and sea lions (Otaridae)
3. Walruses (Odobenidae)

57. SEALS:
Do not have an ear that extends from the skull, but they can still hear well. 
Propel themselves through the water with their rear flippers.
Front flippers are used for steering. 
The front flippers of seals are short with sharp claws.  Seals cannot use their rear flippers to walk on land or ice and most appear awkward when moving on these surfaces. 
Seals have a torpedo like shape in the water and use their rear flippers to move rapidly to catch prey and escape predators. 

58. Largha (spotted) seal

59. Crabeater seals

60. Crabeater seal skull with blowup of the special teeth that are used to filter the krill from the water

61. Ribbon seal

62. Harbor seal

63. Spotted seal

64. Sea Lions and Fur Seals
Fur seals and sea lions have ears that extend from the skull.  The front flippers of fur seals and sea lions are used to propel them through the water.
Sea lions have a rounded snout and their fur is courser and shorter than a fur seal. 
Sea lions are the larger of the two. 
Fur seals have a longer, pointer snout, their fur is longer and finer, and their flippers are longer. 

65. Steller sea lion

66. Northern fur seal pup

67. Northern Fur Seal pup

68. Steller Sea Lion pups

69. Northern Fur Seal Bull.  Notice the thick fur, the fur is thick enough that it is waterproof

70. Galapagos Sea Lion

71. Walrus
The Walrus lives in the Arctic circle and spends much of its day in open water or near the shore resting on ice floes

72. Sometimes the blubber on a walrus will be over 6 inches deep to keep the animal from freezing to death

73. Sirenians-Manatees and Dugongs
Sirenians spend their whole lives in water.
Manatees are aquatic mammals that are called sea cows (named this by Georg Wilhelm Steller, because they taste like beef).
These plant eaters are slow swimmers; they have two flippers, each of which has three to four nails on the end (there are no external hind limbs).
Short whiskers adorn the short, boxy snout.
Manatees are closely related to the elephant

74. Manatees migrate along the coast
Manatees migrate along the coast. North American manatees winter in Florida, as they prefer warm water.
Amazonian manatees

75. Antillean manatee

76. Florida manatee

77. Dugongs
The dugong lives in the shallow water of tropical seas off the coasts of East Africa, Australia, India, the Phillippines, and other islands in the South Pacific.
Dugongs look different from manatees.
Dugongs have pointed tails ( many manatees have a small notch in the tail) and one pair of tusk-like teeth.
Dugongs are seldom found in fresh water.

78. Duodong
Dugongs rest in the deep water during the day and move towards the shoreline at night to feed. The dugong uses its flippers for balance and moving along the ocean floor as it grazes. Dugongs are not thought to migrate as far as the manatees do. Like manatees, dugongs are usually found in small groups are alone. But groups of thousands of dugongs have been seen occasionally.

79. dugong or sea cow

80. dugong or sea cow

81. Other Marine mammals
Two species that are also considered marine mammals are the Northern Pacific sea otter and the South American sea otter. 
Sea otters are notable because they are the only marine mammal species that use tools to forage for food.

82. Sea otter

83. Sea otter

84. Polar bear
The polar bear is also considered a marine mammal because it is a proficient swimmer, which hunts primarily on sea ice for ringed and bearded seals

85. Polar bears…
marine mammals unique to the waters of the circumpolar Arctic, and is found in the wild in five countries: Canada, Greenland (territory of Denmark), Norway, the USA, and the former USSR, as well as on the high seas where jurisdiction is not clearly defined.

86. current wild population of Polar bears is estimated to be between 21,000 and 28,000 individuals.

87. The average land Polar bear is 2. 5 to 3 metres long
The average land Polar bear is 2.5 to 3 metres long. Males grow to 2 or 3 times the size of females.