MARINE SCIENCE. Monday 21 May 2018

Transcription

1 MARINE SCIENCE Monday 21 May 2018

2 Entry Task What was one of the major types of sea mammals named in the video? Pinnipeds When was the Marine Mammal Protection Act established? 1972

3 Agenda Housekeeping Mammals of the Sea Video Unit_16 Marine Mammals

4 Housekeeping Memorial holiday this weekend, May. No School!

5 Mammals Of The Sea (29:04): Video Synopsis: "Mammals of the Sea" discusses historical intersections between humans & marines mammals, & the impact of the Marine Mammal Protection Act, which was passed by Congress in The film also examines ongoing tensions between those in favor of full protection for marine mammal populations and those concerned about the toll that marine mammals exact on commercial fishing opportunities. Note: The Mammals of the Sea question worksheet can be located on the Marine Science link:

6 Marine Mammals Marine Mammals - Back to the Sea Other Marine Mammals Sea Otters (member of weasel family) Polar Bears (member of bear family) Classification of Marine Mammals Sirenians Pinnipeds Cetaceans Manatees Dugongs Steller s sea cow Fur Seals Sea Lions Walruses True Seals Toothed Whales Baleen Whales Roqual Whales Right Whales Gray Whales Dolphins Porpoises

7 Polar Bears: Living on the Ice Marine Mammals Polar bears are most adapted to living on land. They live on ice floes (pieces of floating ice) & on shore in the north polar region.

8 Polar Bears: Living on the Ice Marine Mammals They have thick fur & a thick layer of blubber. Hair has two layers; an outer layer of long guard hairs & a thick undercoat of shorter hair.

9 Marine Mammals Polar Bears: Living on the Ice They have thick fur & a thick layer of blubber. Guard hairs are made of a protein called keratin. - Mostly transparent (clear). - Coarse, tapered & have a hollow core filled with air.

10 Polar Bears: Living on the Ice Polar Bears are mainly solitary animals. Seals are their favorite food source. Stalk seals that are relaxing in the sun Catch seals that pop up through holes in the ice. Marine Mammals

11 MARINE SCIENCE Tuesday 22 May 2018

12 Entry Task How many layers of fur do polar bears have & what are the layers? Two layers; the longest are the guard hairs & short, thick undercoat. What color are the guard hairs of polar bears? Transparent (clear)

13 Agenda Housekeeping Unit_16 Marine Mammals

14 Housekeeping Memorial holiday this weekend, May. No School!

15 Polar Bears: Living on the Ice Polar Bears are mainly solitary animals. Seals are their favorite food source. Stalk seals that are relaxing in the sun Catch seals that pop up through holes in the ice. Marine Mammals

16 Sea Otters: Tool Users Marine Mammals Smallest of the marine mammals. Commonly found in the giant kelp beds along the rocky California Coast. Carnivorous animals that eat many different types of ocean creatures. Sea Urchins Shellfish Other marine invertebrates

17 Sea Otters: Tool Users Marine Mammals They spend much of their time diving for food. One of the few marine food. mammals to use tools to get to their food. When eating abalone the When eating abalone the shell must be cracked open. When floating on their backs they place the abalone on their stomach & hit it with a rock until it opens

18 Polar Bears 101 (3:25): Marine Mammals Synopsis: How do polar bears survive their Arctic habitat? Is climate change affecting their population? Learn how polar bears have adapted to life on top of the world. videos/polar-bears-101 Sea Otters 101 (3:07): Synopsis: TBD

19 Marine Mammals Bradycardia: Surviving Long Periods without Oxygen All mammals must breathe. The heart pumps blood throughout the body carrying oxygen to the tissues & removing waste, CO 2. Any interruption threatens a mammals life.

20 Bradycardia: Surviving Long Periods without Oxygen All mammals must breathe. Marine Mammals Not all tissues need a continuous supply of fresh air. - Most body parts can survive asphyxia (too little oxygen). The heart & brain are extremely sensitive to asphyxia. - Suffocation & heart failure kill a human within a few minutes. - The brain can suffer irreversible damage if circulation stops for more than five minutes.

21 Marine Mammals Bradycardia: Surviving Long Periods without Oxygen Marine mammals often dive & remain underwater for periods longer than five minutes. Marine Mammals Sea Otters Porpoise Dolphin Killer Whale Manatee Sea Lion True Seal Sperm Whale Time of Breath Hold & Depth of Dive Maximum Breath Hold (minutes) Depth (meters) ,200

22 Marine Mammals Bradycardia: Surviving Long Periods without Oxygen How do marine mammals avoid the problems of asphyxia during their very long dives? Simplest answer = large capacity for storing oxygen. - But, examinations show lungs are not unusually large. However, studies show they exhibit bradycardia - Bradycardia = slowing down of heartbeat when animal is submerged.

23 Marine Mammals Bradycardia: Surviving Long Periods without Oxygen How do marine mammals avoid the problems of asphyxia during their very long dives? They also close circulation to many body parts while maintaining circulation to the heart & brain. - Reduce blood supply to their muscles, intestines, & parts of their lower body.

24 Manatees 101 (3:39): Synopsis: TBD Marine Mammals Dugongs (2:25): Synopsis: The slow and gentle dugong has developed an interesting strategy to avoid its nemesis, tiger sharks.

25 MARINE SCIENCE Wednesday 23 May 2018

26 Entry Task How are marine mammals able to remain submerged for long periods of time? They have the ability to slow down their heartbeat (bradycardia). They also close circulation to many body parts while maintaining circulation to the heart & brain. What two vital organs are extremely sensitive to asphyxia? Heart Brain

27 Agenda Housekeeping Unit_16 Marine Mammals

28 Housekeeping Memorial holiday this weekend, May. No School!

29 Manatees: The Gentle Giant Marine Mammals Manatee populations in the U.S. are concentrated primarily in Florida In winter they go to springfed coastal areas to feed & keep warm. Little is known about their summer ocean migrations.

30 Manatees: Anatomy Marine Mammals Split lip lets each lip move separately to manipulate plants & specialized sensory bristles & hairs discriminate while feeding. Endless supply of molars known Endless supply of molars known as marching molars. Form in the rear, six to seven Form in the rear, six to seven on each side of the jaw. As older molars in the front become worn & fall out they are replaced by those in the rear. Teeth are worn down by abrasive plants mixed with sand.

31 Manatees: Anatomy Average measurements: 10 feet in length 800-1,200 pounds Largest: 13 feet in length Over 3,500 pounds Females are generally larger than males. Marine Mammals

32 Manatees: Anatomy Skin is about 2 inches thick. Marine Mammals Not thick enough to keep out the cold Susceptible to colds & pneumonia. Unable to withstand temperatures below 65 F for any length of time. Often die when severe cold spells occur.

33 Marine Mammals Manatees: Anatomy Front limbs are paddle-shaped flippers. They do not have hind limbs, but instead have a fan-shaped tail. No external ears & very small eyes.

34 MARINE SCIENCE Thursday 24 May 2018

35 Entry Task What is unique about the teeth of manatees? They have marching molars, as older molars in the front become worn & fall out they are replaced by those in the rear. Why do manatees spend their time in warmer waters? They are unable to withstand temperatures below 65 F for any length of time & often die when severe cold spells occur.

36 Agenda Housekeeping Unit_16 Marine Mammals Lab Activity #3 Sirenian Lecture

37 Housekeeping Memorial holiday this weekend, May. No School!

38 Cold Blooded Swimmers Unit_16 Marine Mammals Lab Activity #3 Grab a copy of the activity worksheet. Find a partner Follow the instructions provided in the activity. Note: The Unit_16 Marine Mammals Lab Activity #3 Lab Activity #1 worksheet can be located on the Biology link:

39 MARINE SCIENCE Friday 25 May 2018

40 Memorial Weekend Get out & enjoy the beautiful sunshine!!