All penguins rely on mainly three sources of food; krill, squids, and fish. They come from the bodies of water that the penguins live by. Larger varieties of penguins, such as emperor penguins, eat more fish and squid compared to krill, but may still eat some krill. Smaller species eat mainly krill and squid. Also, the farther north the penguins live, the more fish they eat. They dive up to over 18m to feed. They swallow their food whole while swimming.