Which Animals Are the Fastest?

Three cheetahs

Because wild animals cannot be put on measured courses, judging their speeds accurately is difficult. Unintentional exaggerations are common. A slithering snake, for example, looks deceptively speedy, but few go faster than three or four miles an hour. Even the swift African black mamba does well to reach eight miles an hour.

Many sources call the spine-tailed swifts of Asia the fastest in the animal world: careful timing with a stopwatch indicates a flight speed of about 105 miles an hour. The plummeting dives of peregrine falcons have been clocked at 85 miles an hour — fast indeed, though their speed has sometimes been estimated at double that rate.

The fastest runner is the long-legged cheetah, which can reach a speed of 70 miles an hour within a few seconds after starting. It can maintain this sprinting speed for only about 15 seconds, but that is generally long enough to catch such fleet-footed prey as antelopes. Antelopes are no slowpokes themselves. They can accelerate quickly to 60 miles an hour and continue at that speed for several minutes, then run for half an hour or longer at nearly 40 miles an hour.

The fastest of fish are the marlins, swordfish, and sailfish, which often attain speeds of 45 to 50 miles an hour (possibly more in a spurting dash). Whales and porpoises can go only about half as fast — still speedy enough to pass most ships at sea.