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					(Pre-visit) Grade Level: 6th-8th Purpose: To have students learn about different types of food that sharks eat, the natural pressures they are facing and the additional stresses placed on shark populations by humans. Materials:  1 rope length to mark starting line  Multi-colored pieces of construction paper  Open area for running  Watch and whistle Teacher Background Information: Sharks are fascinating but frequently misunderstood animals. There are approximately ~375 species of sharks in the world and these animals live in all types of environments ranging from the tropics to the artic. Sharks are apex (top) predators of the sea and help maintain the health of the oceans by removing sick and injured fish. Unfortunately, sharks are facing several challenges both natural and human related. Sharks, as a species, take a long time to reach maturity and often species do not reproduce in large numbers. As sharks are fished for sport, industry and in response to human fears they are rapidly dwindling in number. In fact, some scientists fear that certain species will go extinct before we have time to save them. Sharks are also facing increasing amounts of pollution and a dwindling supply of food as some of their prey disappears. Procedure: 1) At the start of the activity spread the pieces of construction paper around the field making sure that the pieces are scattered. 2) Have kids line up at the rope. Explain that each kid is a shark and that the construction paper pieces are pieces of food. Each shark needs to get enough food to survive in the given amount of time, usually do ~30 second intervals. Each shark needs at least 4 pieces of each color (older kids). For little kids you can give them more time and decrease the amount needed. Green: turtles Red: Fish Blue: crabs Black/Gray: marine mammals 3) When the 30 seconds is up blow the whistle and have all the sharks return to the starting line. Have the sharks count the amount of food each of them caught. Have any shark that caught 1 piece of each color raise their hand (most likely will be everyone). Continue to count upwards until you reach 4 pieces for each color. Those that still have their hands up managed to catch enough food to survive. All the others unfortunately did not make it. How many sharks did survive? 4) Do the game again using some of the following variations: a) Put out less food, play the game again and compare the results to how many survived before. Have the kids explain why it was harder. By putting out less food you are simulating a decrease in available food, which could be due to human over-fishing, food sources becoming endangered, etc. b) Have some of the sharks have injuries (missing fins, trapped in a net—station the shark in one spot, etc.) and have other sharks be parents so they have to have 2 or

3 times as much food as everyone else. Play the game again and see which sharks had the hardest time finding enough food. Why? c) Have all the sharks be babies and have some of the kids be predators. The baby sharks still need to have enough food to survive (3 pieces) while the predators are trying to eat the baby sharks. The predators do this by tagging the shark on the shoulder, once tagged the baby shark has to freeze in place for the rest of the game. How many baby sharks survive? Discussion Questions: 1) What is the biggest problem for sharks? 2) What is the newest industry that is increasing the number of sharks caught each year? How many sharks do humans kill each year? How many humans do sharks kill each year? 3) What would be the effect on the ocean if sharks were removed from the ecosystem? 4) Research one species of shark and learn about its habitat, diet and its current status (i.e. is it endangered, on the decline, a shark that is hunted, etc.)


				
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posted:11/27/2009
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