Activity Three - Leatherback Turtles

Counting Leatherback Turtles and Marine Mammals

Materials:

• Legal size envelopes
• 3 or 4 legal size pieces of paper or computer paper that will fit inside the legal size envelope
• Scissors and transparent tape
• Pencil or pen

Let's get started!

In this activity we will explore how scientists use aerial surveys to study whales and other marine animals. We will also discover some of the challenges involved in using a plane for such surveys.

Part One:

Get into your group and decide who will be the pilot of the survey plane and who will be the scientists.

1. Take the legal size envelope and cut off both ends so a piece of paper can slide right through the envelope. 
2. In the top third of the envelope cut a square 'window' so that as the paper slides through the envelope you can see it as is passes by the 'window'.
3. Take the legal paper and attach three or four sheets together end to end with transparent tape to make one long sheet, or use an equivalent length of computer paper that will fit through the envelope.
4. At one end of the paper attach a pull-tab to help you pull the paper through the envelope. You can make this out of paper or use a cardboard bookmark.
5. The pilot should go to a separate part of the classroom and draw small circles randomly over the paper. These circles will symbolize the leatherback turtles or whales. The pilot will need to know the final number of spots, but must not tell the scientists.
6. The scientists gather around the pilot who then slides the paper through the envelope at a steady but fast rate.
7. The scientists count the spots as they pass in front of the 'window.'
8. The scientists should then compare their numbers and the 'pilot' can reveal the actual number of marine mammals on the paper.

Variation:

You can make this exercise more realistic and more difficult by varying the size of the spots. Big spots can be large whales and smaller ones can be leatherbacks and small whales. Have scientists count both or try to distinguish the spots from each other.

Talk about it!

1. Did any of the scientists get the number of leatherback turtles and whales right?
2. What are some of the challenges of counting marine mammals from airplanes?
3. Can you think of other ways to count marine mammals?
4. Why do we need to count marine mammals?