The Wonderful World of Marine Mammals

Sea Otters – eat mostly urchins, crustaceans and some fish Almost hunted to extinction, but conservation management efforts restored population.

Pinnepeds – “featherfooted”  All come to shore to give birth and molt  Found in all oceans  Eat fish and larger invertebrates  Kingdom – Animalia  Phylum – Chordata  Class – Mammalia  Order - Carnivora

Diving in Pinnepeds  Can stay under for over 45 minutes  Exhale air in lungs to become less bouyant  Metabolism and hr slow  Blood is redistributed to vital organs(brain and heart)  Record depth – female northern elephant seal – 4,125 feet

 Three families –Eared seals – seal lions and fur seals Use forelimbs to swim – true seals(phocids) – Use hind flippers for movement –Walruses Canine teeth have become tusks in males Found in arctic region Family is one large bull that presides over a harem

Fur seal Sea lions External ears Large flippers used for propulsion Eared Seals True Seals Ribbon seal Elephant seal

Walruses

Mantees and Dugongs  Kingdom – Animalia  Phylum – Chordata  Class – Mammalia  Order - Sirenia

Manatee – three species, can inhabit both marine and fresh water Dugong – completely marine, head bigger and flippers smaller than manatee

 Kingdom – Animalia  Phylum – Chordata  Class – Mammalia  Order – cetacea –Whales, dolphins and propoises Nostrils have become a blowhole at top of head Streamlined body Blubber layer under skin(insulation and energy) No external ears – reduce resistance Forelimbs modified into flippers Counter current heat exchange system Tail is fluke – moves up and down Hair reduced Countershading

Adaptations for diving  Takes in breath and blows it out –makes less bouyant  Cetaceans have extremely large lungs with large numbers of alveoli – take in more oxygen  Lungs and rib cage can collapse  Metabolism and hr decreases  Blood shunted to vital organs  Medulla oblongata( area responsible for controlling breathing) is less sensitive to CO 2  Contain large amounts of hemoglobin  Have a large volume of blood compared to other mammals  Muscles less sensitive to lactic acid

Cetacean behavior Spy hopping – “hey what’s going on up here?” A little to close

Breaching- establishing dominance or just having fun

Fluke up Flipper flapping – say it five times fast Tail flapping

Types of whales  Toothed –Smaller and shorter –One type of tooth for catching and holding –Higher on food chain – higher trophic level –Echolocation for hunting –Ex. Killer whale, sperm whale, dolphin  Baleen –Much larger and longer –Baleen – overlapping plates to filter prey made of keratin – protein that makes up hair and nails –Eat plankton, krill and small fish –Use bubble net to trap prey

Baleen plates

Baleen whale feeding

Blue whale – largest animal

Toothed Whales – dolphins, porpoises, killer whales, sperm whales and narwals Sperm whale – named for fluid I animals head used in oil, candles, waxes and lubricants Ambergris – a digestive by product – used in perfumes Spermaceti – fluid in head used in echolocation to catch prey(giant squid and cuttlefish)

Dolphins and Porpoises – what’s the difference? Dolphins have a beak Porpoise head is rounded off with no beak This porpoise was harasses to death by a pod of dolphins

Narwhals

Killer Whales - orcas

Echolocation  Acts like sonar  Orientation clicks – give an animal a general idea of surroundings  Discrimination clicks – give precise picture of a particular object.

Whale songs