When our penguins aren't diving into or rocketing out of the water, swimming or eating, you'll see them working on their feathers. Preening is important to all birds, but maybe more so to aquatic birds like penguins. Their feathers have to be waterproof so they can zip through the water like they do and dry off quickly when returning to land. The gentoo in the picture above is reaching back to a special gland near the tail. The uropygial gland produces a waxy substance the penguins spread over the rest of their feathers to keep them waterproof. Preening also realigns the feathers so they interlock with microscopic hooks. If you look closely at one of our penguins you'll see how smooth they look with those incredibly tight fitting feathers. Sometimes you'll see something funny when a penguin is preening the feathers on it's head. Since it can't reach the top of his head with it's beak, the penguin leans way over while standing on one foot. Then the other foot reaches up and begins a scratching motion. It's really one of the more comical things penguins do. As they keep scratching the top of their heads, you can almost hear them saying, "OH YEAH! That's the spot."