Penguins eat mostly squids, fish, and krill. Krill are small crustaceans-relatives of shrimps, crabs, and lobsters.
Penguins feed at sea.
They catch prey with their strong bills and swallow it whole. All penguins are dark on their back and white on their chests. Their white belly make the penguin hard to see from underneath, camouflaging it from both predators and prey in the water. The dark back blends in with the dark waters of the ocean when viewed from above, making the penguin hard to spot by a predator looking down. On the other hand, if a hungry killer whale or leopard seal approaches from underneath, the penguins' white belly makes it almost invisible against the sunny surface of the sea.