They can dive very deep. Their wings are more like firm paddles that help propel them through the water and they use their feet and tail as a rudder. They can travel through water at about 5 mph, and when you watch one swimming along it is almost like watching a porpoise because a penguin leaps out of the water every several feet, which is how they are able to breath. Occasionally, you see a penguin suddenly leaping out of water surprisingly high into the air and then landing on the edge of a rock or an iceberg. It looks like a circus act and you feel like applauding the little guys.
Penguins are fun to watch.
They wave their heads and flippers around. They steal stones from their neighbors' nests to add them to their own. And if a couple of them are in a dispute they will stare and point at one another and, occasionally, charge the other one. To attract a female, a male will pump his chest, angle his flippers, stretch his head skyward and let out a loud braying sound. Sometimes this touches off a chorus of similar performances from other nearby males.