Emperor penguins
Emperor penguins and chicks
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Emperor penguins (Aptenodytes forsteri) are the largest penguin species. They stand about 115 cm tall and can live to more than 40 years. Depending on the stage of their breeding cycle they weigh from 23 to 40 kilograms. Their closest relatives are king penguins.
Emperor penguins breed in colonies scattered around the Antarctic continent. Colonies range in size from a few hundred to over 20,000 pairs. All but two colonies are situated on the fast-ice (frozen sea) that is locked between islands or grounded icebergs.
Emperor penguins are the only animals that breed during the Antarctic winter.
Emperor penguins are not very territorial. They huddle tightly together and share body warmth during the fierce winter storms.
Because there are no nesting materials, emperor penguins incubate the single egg on their feet. In relation to the body size of the female the egg is rather small; it weighs only about 450 grams.
Only the males incubate the egg while the females return to sea for the roughly 65 days it takes for the egg to hatch. While incubating the males cannot go and feed themselves. By the time the chicks hatch the males have fasted for about 4 months (two months during courtship and two months during incubation).
The chicks are virtually naked when they hatch and die within minutes if accidentally dropped onto the ice. The parents brood the youngsters on their feet for about 50 days.
Emperor penguins are exquisite divers! While they mostly forage at depths from 150 to 250 meters the deepest dive recorded was to 565 meters. On average dives last 3 to 6 minutes but the longest dive on record was 22 minutes.
Their diet consists of a mixture of fish, krill and squid. Most prey items are small; since they are very cold when ingested it makes it easier to bring the food up to body temperature and to digest.
At fledging, young emperor penguins radiate far from the waters near their colonies. They can reach the sub-Antarctic waters up to 12 degrees latitude away from their natal sites.
Links
Taxonomic information on the emperor penguin
Australian Antarctic Science (AAS) projects relating to emperor penguins
Australian Antarctic publications relating to emperor penguins
Emperor penguins: winter survivors
Listen to emperor penguins [48k/12s MP3]
Listen to an emperor sneeze [58k/3s MP3]
Filming a frozen world for planet earth [PDF] - Australian Antarctic Magazine, Issue 9, pp 20-21
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