Wanderlust World Wanderlust World Being aquatic birds with an ocean habitat, the diet of penguins mainly consists of seafood. The birds are carnivorous, sustaining themselves on krill, crustaceans, fish and squid. Their exact diet is determined by where they live, with more diverse diets available to the species living in sub-Antarctic and Antarctic areas. For instance, Humboldt penguins in South America mostly consume small fish, while Rockhopper penguins in New Zealand eat krill and squid as well as fish.
Penguins are efficient hunters, with excellent eyesight and the ability to swim fast and dive deeply. Hunting and feeding generally occurs between 50 and 60 feet below the ocean's surface. Some species can remain underwater for up to 20 minutes at a time. Penguins feed at sea, swallowing their prey whole while swimming. Species such as Adélies and King penguins will travel distances up to 560 miles from their colonies to feed. Penguins also use holes in the ice for feeding when fishing grounds are far away.
Penguins use their spiny tongues, powerful jaws and sharp beaks to catch their prey and swallow it whole. Swallowing whole food allows them to quickly feed on as much as possible without taking time to chew. The size of the species determines the quantity they eat; however, penguins tend to eat more when food is plentiful to build fat stores for times of scarcity and fasting. Penguins hydrate themselves by eating fresh-water snow as well as drinking seawater because their bodies contain glands for secreting excess salt.
Penguins fast annually and build-up fat layers to sustain their energy levels beforehand. According to Sea World, penguins fast during breeding season and will not leave their nests to feed during incubation and nesting periods. The birds also fast when molting because they are unable to enter the water without the waterproofing and insulation provided by their plumage. The period of fasting varies between sex and species, with the male King and Emperor penguins having the longest fasting periods of up to 54 days and 120 days respectively.