Kartchner Caverns’ bat population is predominantly the Myotis velifer or common cave bat. These cave bats use Kartchner Caverns as a nursery colony during the summer months. The rooms that provide shelter for the bats will be off limits to visitors during the summer months to insure that the bats remain undisturbed.

Inside Kartchner Caverns it is so dark that if you were to turn out the lights and hold out your hand in front of you, you would see nothing. So how do bats find their way in and out of the cave to feed each night? They use echolocation. Echolocation is how bats identify and measure the distance to objects in their path. The bats emit short, high-frequency sounds, produced in the larynx, through the mouth or nose. As the sounds come in contact with different objects, they are reflected back to the bat as echoes. With echolocation bats are able to orient themselves in space and to determine the shape, size, texture, speed, distance and direction of movement of prey or other food items. Humans cannot hear most of the noises bats make because they are too high for our ears to detect.

SUMMARY:

1. Locate a large area with few auditory distractions (gymnasium, all-purpose room).
2. To make sure the rolling of the ball is as consistent as possible, assign one person, student or teacher, to be in charge of this duty.
3. Prior to this activity, have the class practice counting seconds.
4. Tell the students they are going to be bats and use their ears to listen for echoes.
5. Discuss the key question: "How can you use sound to determine distance?"
6. Have the students measure three different distances (2 meters, 4 meters, and 6 meters) from the wall. Use masking tape to mark each distance.
7. Have the students record the distances on their activity sheet.
8. Direct all students to sit down except the ball roller.
9. Have the ball roller stand behind the two-meter line and roll the ball to the wall.
10. As the ball leaves the ball roller’s hands, the other students should start counting seconds, and continue until the ball hits the wall.
11. Repeat steps 8 and 9 at each pre-marked distance, making sure the ball is rolled at approximately the same speed each time. Have the students predict what the count will be from each new position. After each roll have the students record the actual count on their activity sheet.

ASSESSMENT:

For class Discussion:

• How did the counts differ at each position?
• What helped the blindfolded students determine their distance from the wall?
• How is this activity similar to bat’s use of echolocation?
• How is this activity different from how bats use echolocation?
• What parts of our body helped us in the blindfolded process of the activity?
• Compare and contrast our ears and faces with those of bats.