Penguins have large heads and long bodies. They resemble humans when they waddle around on their two webbed feet. Their short feathers, which provide excellent insulation against the cold water and air temperatures, are black on their backs and white on their chests, giving the appearance of a tuxedo. Their wings are stiff flippers that help them navigate the ocean waters.
Species vary in size, so penguins can weigh less than 3 pounds (1.1 kilograms) or as much as 88 pounds (40 kilograms). They can stand less than 18 inches (45 centimeters) high, or almost 4 feet (115 centimeters) tall. Males are somewhat bigger than females, but look similar otherwise.
Penguins cannot fly and their bones are much more solid and heavy than those of most birds. This is an adaptation that allows them to dive for food. Penguins differ from other birds in that, except for a patch on their bellies, their entire bodies are covered with feathers. Birds usually have feathers growing only in certain sections of skin.
The Galápagos penguin lives just north of the equator, but all other species live in the southern half of the world. Although many equate the penguin with Antarctica, more than half of the seventeen penguin species are never seen there.
Although penguins spend most of their time diving for food, they do venture on land to rest, breed, and raise their young. Breeding colonies are usually near the shore, though some species move as far as 2 miles (3 kilometers) inland. Some breeding habitats are in snow, while others are on tropical islands.
Penguins eat squid, fish, and crustaceans such as crabs and shrimp. What they prefer depends on the species. When they are hunting prey, penguins dive deep and stay underwater for long periods of time. Depending on the species, they can stay underwater for less than a minute up to eighteen minutes at depths ranging from 98 feet (30 meters) to 1,755 feet (535 meters).
BEHAVIOR AND REPRODUCTION
The social penguin likes to live in groups of various sizes. They are rarely without each other’s company and so have developed behaviors that allow them to live harmoniously for the most part. When they do fight, penguins use their flippers for hitting and their bills are used like swords.
Most penguins are somewhat monogamous (muh-NAH-guh-mus; have one mate), though they have been known to “divorce” and find new mates when a new breeding season begins. They engage in mating rituals and are able to find their mates in a crowd based on these rituals as well as by voice. Penguins are ready to breed between the ages of two and five years, with the female being ready somewhat earlier than the male.
Depending on the species, penguins lay one to three eggs. The incubation period lasts from thirty-three to sixty-four days, and chicks will hatch at the same time or within one day of each other. Once born, parents take turns caring for the chicks and hunting for food. The food-provider eats the prey, then regurgitates (re-GER-jih-tates; vomits) it for the chicks to eat. Once the chicks are old enough to eat and take care of themselves, parents continue to protect them.
Though adult penguins have no land predators, they do fall prey to sharks, leopard seals, sea lions, and killer whales. On land, chicks and eggs are often eaten by other birds.
In the wild, penguins can live up to twenty-five years.
PENGUINS AND PEOPLE
Historically, penguins were killed for food and the extraction of the oil that lay in their fat. The oil was used for lighting and fuel. Penguins are easy prey because they are not afraid of humans and so are easily captured. In the days of the explorers, it was common for the adventurers to kill three thousand penguins a day for food.
Despite protection, penguins are still illegally hunted for use as bait and as a food source.
Twelve species are included on the 2003 IUCN Red List of Threatened Species. The Galápagos, erect-crested, and yelloweyed penguins are Endangered, facing a very high risk of extinction; seven species are Vulnerable, facing a high risk of extinction; and two are Near Threatened, in danger of becoming threatened with extinction.