BOB HIRSHON (host):
Just how speedy are dolphins? I’m Bob Hirshon and this is Science Update.
Listener Calvin Hamilton of Gainesville, Florida wrote to ask whether it’s true that dolphins can swim as fast as 20 miles per hour. According to marine biologist Frank Fish of West Chester University, they can sometimes swim even faster than that.
FRANK FISH (West Chester University):
The highest speed that’s ever been recorded was for the killer whale, which is the largest of the dolphins, and its speed was about 34 miles per hour.
He says bottlenose dolphins and Dall’s porpoises are just as fast. He adds that high speeds create drag, and for many years scientists didn’t understand how dolphins could swim as fast as they do. Recent studies have shown that dolphins can produce enough thrust to resist the drag. If your head’s swimming with science questions, call us at 1-800-why-isit. I’m Bob Hirshon, for AAAS, the science society.