Gentoo Penguin—Distribution and Migration
|GENTOO PENGUINS VIDEO|
Despite a wide distribution between 46° and 65° south latitude, the gentoo penguin (Pygoscelis papua) population—estimated to be from 250,000 to 300,000 pairs—is less than the other brush-tailed species, the chinstrap and Adélie penguins. The majority of these pairs are located in the Falkland Islands of the South Atlantic, the Kerguelen Islands of the South Indian Ocean, and on South Georgia, an island in the Southern Ocean. Colonies located further south on islands off the Antarctic Peninsula are scattered and, although they disperse after breeding, it is too general to be considered a true migration.
Identifying Gentoo Penguins—Physical Characteristics
With their bright orange bill and orange-pink feet, gentoos are considered the most colorful of the Pygoscelis or brush-tailed species. They have the characteristic black back and white underparts as the other species, but sport a white band that is widest at the eyes and forms a triangle that connects with a thin band across the top of the head. There is some white spotting, that varies among birds, on the tops of their crowns and the sides of their heads. Their flippers blush pink on the undersides. The gentoo is the only orange-billed penguin with a distinctive white patch above the eye.
Juveniles have less distinct triangular eye patches and their colors are duller, gray instead of the black plumage of the adult with muted pink undersides of the flippers. Chicks are silvery-gray when they hatch and, within a week, are white on the undersides from the chin down.
|Gentoo penguin hopping onto rock in Antarctica|
Gentoos are the third largest species of penguins, after the great penguins (kings and emperors). They have been recorded to be 30–36 inches in height and can weigh over 18 pounds at the height of the summer season. However, these statistics have been documented to vary with latitude. The length and weight increases as the latitude decreases (as they get farther from the Antarctic Peninsula) and it is believed that there are two subspecies—papua, which is generally larger, on subantarctic islands, and ellsworthii, which has smaller flippers, feet and bill, found south of 60° south latitude on the Antarctic Peninsula and Southern Ocean islands.
Gentoo Penguin Habitat
Unlike the other brush-tailed species, gentoos only breed in snow- and ice-free areas, even though that may include the Antarctic Peninsula. But, because they have such widespread distribution in the southern latitudes, their attributes and habits vary with the region. For example, on the Antarctic Peninsula, they inhabit pebble beaches whereas, on subantarctic islands, their preferences can include areas cluttered with twigs and seaweed.
Gentoo Penguin Diet
As with features of their breeding sites, their diet varies considerably among colonies as well as years. On the Antarctic Peninsula, they eat mainly krill and supplement with fishes. On subantarctic islands, their diet varies from primarily fish to primarily krill, depending on the colony site and the time of year.
During the breeding season, they tend to stay close to the colony, foraging along the shorelines and staying within 18 miles of the colony.
Gentoo Penguin Behavior
Of the brush-tailed species, gentoos tend to be the shyest and make little effort in defense of their territory. They will point their bill and back off from predators, such as skuas, doing little to discourage the looting of their nest.
Gentoo Penguin Breeding and Mating
|Gentoo penguins vocalizing|
There are huge differences in their breeding biology depending on whether their rookery sites are in the subantarctic islands or in the islands further south near the Antarctic Convergence (where the great oceans—the Atlantic, Pacific and Indian meet the cold waters of the Southern Ocean that surrounds Antarctica). Temperature has the greatest impact, influencing timing of the egg laying and synchronization (whether egg laying occurs all at the same time or not). In the subantarctic islands, egg laying can begin as soon as early June (the beginning of winter in the southern hemisphere), but on the Antarctic Peninsula it cannot begin until December. Egg-laying windows range from 135–154 days in the Falkland Islands to 16–28 days in the more southern regions. Those with longer windows have time to lay replacement clutches should the first perish to predation or weather events.
Another feature that differs among colonies is the distance between nests, which is only about a meter at the Antarctic Peninsula and at least two meters further north. The male gathers the materials for the nest and, as he plucks a feather here and a rock there, he doesn’t seem to mind if he steals them from another pair’s nest—and heated arguments occur. It is not unusual for the colony to move from a site that was left trampled and covered with waste from the year before to a "greener" site just down the way.
In attempting to attract a female, a male will trumpet skyward, at which point the female will approach and, if interested, the two will point their bills toward the nest.
Gentoo Penguin Social Behavior
These are social penguins and stay close to the colony site year-round, except for those in the southernmost locations. Although monogamous through the breeding season, pair bonding frequently lasts no longer than 2 to 3 breeding seasons.
Gentoo penguin surfing
at Cuverville Island,
A pair of gentoos
Gentoo penguin at
Coming ashore at