GENUS & SPECIES
• Modified, flipperlike wings drive this flightless seabird through the icy but nutrient-rich seas around Antarctica
• Crowded breeding colonies of up to a quarter of a million birds stretch over rocky coastal slopes
• Parents take turns incubating their two eggs, each fasting for days while its mate is feeding out at sea
WHERE IN THE WORLD?
An adelie penguin is rarely alone. At sea it feeds in flocks under pack ice; in breeding seasons, it treks along bustling routes between the water and its sprawling colonies.
The adelie penguin spends nearly all its time at sea in pack ice that surrounds Antarctica. When it comes ashore to breed, it lands on barren beaches and rocky coastal slopes to gather in huge numbers. After breeding, the penguin then returns to sea, swimming in groups to new feeding grounds as winter ice begins to push farther north.
A Tip of the iceberg Adelies inhabit ice-filled seas, rarely open water.
Ice skating Adelies jump and slide between the sea and the colony.
The adelie penguin is an F excellent swimmer, but is clumsy on land. With its * legs set so far back on its ‘ body, it has to walk upright and can manage only an awkward, almost comical, shuffle on its short, stiff legs. It hops nimbly over rocks and f other low obstacles, but drops onto its breast at the top of ice slopes and toboggans over the ice — making better progress than by walking.
FOOD & FEEDING
The word penguin derives from pinguis, Latin for fat. This is a reference to the thick layer of body fat which lies beneath a penguin’s plumage.
An adelie penguin loses almost half its bodyweight in the annual molt, which takes place on pack ice during February or March.
Two colonies of adelie penguins in the Ross Sea, at Cape Adare and Cape Crozier, hold 280,000 and 180,000 pairs, respectively.
To land on beaches, adelie penguins surf in on the waves.
The adelie penguin stays close to Antarctica’s pack ice to feed, since krill (tiny crustaceans that form its main food) eat the algae that grow on the underside of the ice. Diving to 65 ft for krill and other prey, the penguin can remain underwater for up to seven minutes. It catches faster-swimming prey — squid and fish — by putting on sudden spurts of speed while cruising along underwater
Each feeding trip may last four hours or more; frequently, the adelie feeds at night, taking advantage of the nightly migration of krill and squid to the surface. Flocks also travel many miles around the fringes of the ice to exploit the best feeding grounds.
Filling meal Chicks over two weeks old are fed every two days.
A Waiting in line Before leaving to feed, groups gather on the shore.
1 Hello again
Up to 80% of adelie penguins are faithful to their partner of previous years when they return to land. The birds greet each other eagerly.
Standing face-to-face, with heads held high and bills to the sky, the pair makes a braying sound. This reaffirms the pair-bond.
The pair share responsibility for the young, taking turns incubating the eggs and brooding the chicks while the other feeds at sea.
After fasting when on nest duty, the penguin may spend up to 22 days at sea feeding, building up its reserves for its next shift.
With a total population of four to five million birds, the adelie penguin isn’t threatened. However, many colonies are close to scientific installations, and ever-larger numbers of tourists arrive in Antarctica to photograph its breeding colonies. Some colonies are fast declining due to this human disturbance.
A Warm at heart A youngster with new feathers replacing its down.
A Seabird city Nests are densely packed; neighbors squabble noisily.
Penguins return to breeding colonies in September. Each pair occupies, then defends, a nest site before enacting complex mating rituals.
Two chicks hatch following six weeks of incubation by both sexes. While one parent feeds at sea, the other guards and broods the young. After two weeks, the adults feed together; all the colony’s chicks in the same stage of growth join up in “creches,” which offer security against predators, such as gulls. Chicks fledge after eight weeks and head to sea.
The rockhopper penguin (Eudyptes chrysocome) is slightly smaller than the adelie and more widely distributed over the Antarctic. It shares the adelie’s dumpy appearance and blackish-blue and white plumage, but has more elaborate facial decorations.
Above each eye and behind the cheeks is a thin crest of golden tassels, which the rockhopper raises in courtship displays. A black crest at the back of its head is just as mobile.The rockhopper also has a thick, compact bill for catching crustaceans, such as krill.
|7-13 lbs. (varies with seasons)|
|J-Sexual Maturity||5-8 years ‘|
|Breeding Season||Arrives at nesting colonies in Sept. and Oct.; lays eggs from Nov.|
|i Number of Eggs||2|
|Incubation . Period||30-43 days|
|Fledging Period||50-56 days|
|i Typical [ Diet||Crustaceans (amphipods and krill); some fish and squid|
|Lifespan||Unknown;!”; probably 10-15 years or more|
• The Spheniscidae (the penguins) is the only bird family in which all species are flightless and aquatic. Its 17 members are divided into two groups. Fish-eaters, such as the king penguin (below),have long, thin bills; species that feed on krill, like the adelie, have stubby bills.