How do penguins swim so fast?

3. Most penguins swim underwater at around four to seven miles per hour (mph), but the fastest penguin—the gentoo (Pygoscelis papua)—can reach top speeds of 22 mph! Gentoo penguins “porpoise” by jumping out of the water. They can move faster through air than water, so will often porpoise to escape from a predator. (Photo: Gilad Rom (Flickr)) 4. read more

Whenever it needs to breathe, the penguin will periodically swim fast under the water and then use its flippers to leap from the water in an arc. The momentum of porpoising helps penguins when they need to flee quickly from predators. read more