Answer the following questions: Do Now Read the article titled, Sea Turtles Use Earth’s Magnetic Field to Find Home Answer the following questions: According to scientists, how many years have sea turtles been detecting magnetic fields for? What do you think “imprinting” means? What is the difference in evidence researchers found in this study compared to previous studies? How do magnetic fields change? Did the turtles shift their nesting locations as magnetic fields changed? Was there a correlation? https://www.youtube.com/watch?v=eU4mTAaWb6k

Marine Mammals

Marine Mammal Classification Animalia Chordata Mammalia Pinnipedia Sirenia Cetacea Seals Dugong Toothed Whale Sea Lions Manatee Baleen Whales Walruses

Pinnipeds Seal Sea Lion Walrus

Sirenians Dugong Manatee

Cetaceans Toothed Whales Baleen Whales Beluga Orca Sperm Whale Pilot whale pod Orca Beluga

What are the things that make a marine mammal a mammal? Vertebrates Warm blooded Breath air through lungs Live birth Mammary glands Hair Also, usually large brains and different shapes and sizes of teeth

for life in a wet, cold and salty place. How is it that these mammals are able to survive in a marine environment? ADAPTATIONS for life in a wet, cold and salty place.

Swimming Streamlined body to reduce drag Powerful, efficient appendages Efficient use of O2 in lungs O2 is stored in blood (myoglobin) and muscles Voluntary and conscious breathing Collapsible lungs, thick cartilaginous trachea to tolerate pressure changes High tolerance to lactic acid- muscles can work anaerobically

Thermoregulation Large body, small surface-to volume ratio reduces heat loss Blubber and/or underfur Complex circulatory system conserves and dissipates heat

Water Conservation Use freshwater from food, inhaled air and blubber Remove salts from bodies using many small kidneys

Marine Mammal Evolution Life evolved in sea 3 billion years ago Ancestors in and out of sea, on and off of land as food was available. Whales and dolphins share a common ancestor with sheep, cows, pigs, giraffes? Related to hippos? Manatees relatives of elephants? Seals relatives of bears or canines ? 12

Evolution of a Seal

Evolution of a Whale PHYSICAL ADAPTATIONS: Feet to Flippers- Front legs became paddle-like for steering Hind legs disappeared Nostrils to Blow hole- Moved to the top of the head and became blowholes Quick breathing while swimming Tail to Fluke- Animal tail widened into horizontal flukes for swimming Body Shape- Became sleek and torpedo-shaped “streamlined” for movement through water

Do Now Name 2 types of marine mammals How can marine mammals dive so deep with increasing water pressure? What specific evidence shows that whales evolved from land ancestors?

Breathing Air is precious and in short supply while diving. A seal’s heart rate slows when diving and blood is directed away from extremities towards heart, lungs and brain. Whales have double the amount of blood and # of red blood cells than land mammals.

Temperature Cold is a problem for many marine mammals - water conducts heat 25x faster than air. *Blubber to insulate and streamline *Blubber as stored energy Seals have braided arteries so that cold blood is warmed. Some whales have blubber 20 inches thick!

Types of Pinnipeds Phocidae Odobenidae Otariidae True Seals Walrus Sea Lions Fur Seals

True Seals - Phocidae Harbor Seal – Phoca Vitulina Most common to LI 1.2-1.8m. (5.5ft., 250 lbs., females smaller, 200lbs.) Variable gray color with dark spots Piscivorous - Squid, mackerel, flounder, herring and crab, 12 – 15lbs./day Found in North Pacific and North Atlantic, Hudson Bay Summer in the Gulf of Maine and north, they breed there and find food. Come to LI late November – April, sometimes longer Pups born mid-May – July, 75 cm, 10kg, swim from birth weaned in 3 – 4 weeks, mother’s milk 50% fat

Other True Seals Harp Seals – Pagophilus groenlandica - big spots and blotches, like dalmatians. Whiskers are cat-like, bushy and thinner. Can grow to 6 ft., 400lbs. Hooded Seals – Cristophora cristata - blue backs, can grow up to 9 ft. and 900lbs., females 7 ft., 670lbs. Gray Seals – Halichoerus grypus - horse heads, long snout, molt in June. Can grow to 7.5-8 ft., 800lbs.

Types of Cetaceans Mysticetes_______ Odontocetes Baleen Toothed 2 blow holes 1 blow hole

Baleen Whales - Mysticetes Larger whales including: Blue Finback Humpback Right Gray

Diet and Feeding Mysticetes – Filter feed by catching zooplankton or small schooling fish by skimming or gulping large volumes of prey in water. Tongue forces water to back of mouth past hundreds of baleen plates acting as sieves to trap the prey, then swallow.

Humpback Whale – Megaptera novaeangliae 40-50 ft long, 40 tons Males have complex whale song Feed during summer in Arctic Breaching, Tail flopping Breed and give birth during winter Population dropped by 90% during whaling industry May live 50 years

Fin Whale – Balaenoptera physalus 70 ft long, 70 tons Can swim up to 35 mph Dives for as long as 50 minutes Winters in the Arctic, food rich Summers near Equator, live off fat May live 90 years

Blue Whale – Balaenoptera musculus 75-90ft, 125tons – Earth’s largest animal ever May consume 4 tons of zooplankton each day in summer Summer most frequently off eastern Canada Winter to Florida and Gulf of Mexico May live 80 years

Toothed Whales - Odontocetes Smaller whales including: Beluga Orca Sperm Pilot Sperm Whale Pilot whale pod Orca Beluga Odontocetes

Diet and Feeding Odontocetes have variable number of identical conical teeth or spade shaped teeth used to strain or grasp prey, primarily fish and squid

Sperm Whale – Physeter macroencephalus 60 ft, 70 tons Square head 1/3 length of body Narrow, underslung jaw 36-50 conical teeth in lower jaw only Deepest, longest dives – up to 2 hours, 9,800 ft Present year round in Gulf of Mexico and NC to Georges Bank

Killer Whale – Orcinus orca 30 ft, 8 tons Round head, slight beak 20-26 teeth in both upper and lower rows Highly social Diverse diet to include fish, squid, reptiles, marine mammals More common n. of NJ

Bottlenose Dolphin – Tursiops truncatus 6-12 ft, 140-650 kg Well-defined beak 2 “ecotypes” – coastal, short and slim offshore, larger 40-52 conical teeth, upper, 36-48 lower Groups of 10s to 100s Gulf of Mexico to Cape Hatteras

The Future?

History of Whaling on Long Island Oil - Candles Soap - Furniture Horse whips - Umbrellas Fishing rods - Corsets