What is the only bird that can swim but not fly?

The penguin is the only bird that can swim but not fly. These aquatic birds possess flipper-like wings and can spend as much as three-quarters of their lives in the sea. Penguins are almost exclusively found in the Southern Hemisphere, ranging from northwestern South America to coastal Antarctica.

The Galapagos penguin is the only penguin that lives north of the equator, and its habitat is primarily around the Galapagos Islands.

Some of the 17 to 19 species of penguins can swim as fast as 15 mph, and their distinctive camouflage schemes help them blend into the water while they hunt for their prey.