Learn about the types of rays you can find in New Zealand
See all the eagle ray spotted in New Zealand by other nature enthusiasts.
You will need:
Blow up a balloon and attach it to the heavy object. Does it sink or swim?
What happens when you remove air from the balloon? What happens when you add air?
Challenge: Can you attach the balloon to the object and add juuuust the right amount of air so that it floats in the middle of the water (beneath the surface without touching the bottom)?
This is how fish use their swim bladders to move up and down in the water.
The swim bladder is an internal organ that helps some fish float in the same place despite changes in the water around them. This air-filled sac also allows them to go up or down without having to waste energy swimming.
