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The gentoo is distinguished from other penguins by two white wedges behind the eyes that are connected by a medium-sized line across the top of the head. The wedges are noticeable at a young age, but they are not as well-defined or connected along the top of their head like the adults. The bright dark-orange lower mandible is also a characteristic feature of the gentoo.
Every square inch of the gentoo's body is covered with up to 70 feathers. The 14 to 18 feathers on the tail are about 6 inches long, giving the gentoo the most prominent tail of all penguins.
The third largest penguin, the gentoo stands 27-37 inches and weighs 9-19 pounds. Males are significantly larger than females.
Distribution and Habitat
Gentoo penguins are found between 45 and 65 degrees south latitude. About 40 percent of all penguins live in the Falkland Islands, with the remainder living on South Georgia Island, in the Kerguelen Islands, on many other sub-Antarctic islands, and on the Antarctic peninsula. Only about 13 percent of all gentoo penguins live south of the Antarctic ice pack.
Gentoos are typically found along the rocky shoreline. They prefer elevations of about 375 feet above sea level along the shore because the snow in these areas tends to melt first. The main feature of gentoo habitats is the prevalence of small pebbles, typically under 2 inches in diameter, which are used for building nests.
Like other penguins, the gentoo feeds primarily on fish and crustaceans, supplemented by cephalopods. It tends to feed in shallower water than other penguins, and can also occasionally be found searching for food in inshore waters.
Egg-laying begins from June to mid-August and usually finishes in late October to late November. The prime nesting areas are those that are flat with little to no snow or ice. Once a potential nest site is chosen, the males point their bills vertically in the air and bellow out calls. The calls announce to the females to come and investigate their nest site. If a female "likes" the nest site, the male and female will mutually display by trumpeting or bowing. Gentoo penguins are monogamous during a breeding season, with most pair bonds lasting a lifetime. "Divorces" do occur between breeding seasons, but are fairly rare. In such cases, the female chooses a new partner that has displayed greater reproductive success.
Both parents are involved in nest-building. The nest is bowl-shaped with a wide edge and a hollow center, is 4-8 inches high, and is about 18 inches in diameter. It is made from small stones found around the nesting site, including stones stolen from other nests; molted feathers, twigs, and vegetation are sometimes used as a lining.
The female lays two eggs within 3 days of each other. Both parents defend the nest from other birds that come too close. The eggs are incubated by both parents for about 35 days. For the first three to four weeks, the chicks are guarded in the nest. The parents take turns getting food and regurgitating it for the chicks. Near the end of this stage, the chicks begin to move short distances away from the nest and form groups with other chicks. These groups serve to protect against predators while both parents to forage for the growing young. The young fledge at 70 days old and will enter the sea for the first time. Both parents will still feed their chicks (although not as often) during the fledging period. Sexual maturity is reached at about 2 years of age, but most gentoos don't beginn breeding until age 3 or 4. It is believed that gentoo penguins can live up to 13 years.
If the "original" set of eggs is lost, gentoo penguins can lay a second set of eggs during the same breeding season. These eggs are laid near the end of the breeding season when the female regains sufficient energy.
Gentoos typically dive down only 9-66 feet, with occasional dives up to 230 feet. The longest dive on record is only two minutes long. It is, however, the fastest swimmer of all penguins, capable of reaching 30 miles per hour.
Gentoo penguins typically live in the same place that they breed. The main reason for moving locations is because of ice formation during the winter months, in which case they will move to an ice-free location. They can be found around their breeding colonies all year round, and they forage much closer inshore than the other two Pygoscelis species.
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This page was last updated on June 16, 2017.