The zero g-roll has the same shape as the dolphin bows, called a parabola. The dolphins will also feel weightless during their bows. On the zero g-roll, the weightlessness lasts for several seconds. Fish often have the same density as water and neither sink nor float. Blubber is less dense than water, and a large amount of blubber would insure floating.
Air trapped in feathers or air in the swim bladder of a fish also help in floating.
The boats on the water rides float much higher in the water than do the animals. All Rights Reserved.