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the Legacy continues…………………….
Gregory R. Mann, Ph.D. {ret.}

Emperor Penguin

“Aptenodytes forsteri”

The scientific name for Emperor Penguins is made up of Aptenodytes, which means “featherless diver” and forsteri for Johann Reinhold Forster, a naturalist and colleague of  Captain James Cook in the 18th century who was one of first to describe the penguins. The Emperor is the largest penguin species standing 1.3 meters tall and weighing an average of 45 kilograms. The word Penguin first appears in the 16th century as a synonym for the now extinct Great Auk. When European explorers discovered what are today known as Penguins in the Southern Hemisphere, they noticed their similar appearance to the Great Auk of the Northern Hemisphere and named them after this bird, although they are not closely related. This beautiful species sports the tuxedo style plumage of many penguin species with dark gray to blue-tinged feathers on the dorsal side and a black tail, wings, head, chin and throat. The chest and belly are pale yellow to white. A orange-yellow band appears near the ears on each side of the head that fades toward the neck and chest. The wings are not used for flight; they are used as paddles for swimming. As seen in the movie “March of the Penguins”, the Emperor is subjected to some of the harshest, coldest weather on earth. These amazing birds endure severe weather conditions during the breeding season when temperatures average -62 °C and winds gust up to 192 kph. During these winter storms, they huddle together for protection and share the warmth of the inner huddle by continually rotating from the outer edge to the inner circle. They are well equipped to endure the cold with their four layers of scale-like feathers that even the harshest winds can’t ruffle. They store a lot of body fat used to keep them insulated. Males also store body fat because they fast during the winter breeding months while they incubate the eggs. Emperor Penguins are also able to recycle their body heat because their blood is circulated through their body in a way that cools it as it moves through the arteries and veins toward the extremities (feet, wings and bill) and warms it as it travels back to the heart.

Emperor Penguins are found around Antarctica between 66°S to 78°S latitude. They are a very social species that forage and nest in groups. There are an estimated 40 colonies throughout Antarctica found on ice patches near the sea. Sexually mature adults travel throughout the year between the breeding colonies and the sea where they forage. Between January and March each year, Emperor Penguins can be found in the sea traveling and foraging. They are strong, fast swimmers reaching speeds up to 3.4 meters per second and diving up to 450 meters for up to 22 minutes at a time. They move more slowly on land as they walk an average of 2.8 kph. At times, they “toboggan” by propelling themselves on their bellies across the ice by pushing with their feet and wings. At the onset of the winter months between March and April, adults travel in groups making the long, slow journey from the pack ice near the sea to breeding colonies up to 120 kilometers away. Adults and juveniles are preyed on by Leopard Seals, Killer Whales and sharks. Chicks are preyed on by Skuas and Giant Petrels. They feed on small pelagic (open water) fishes, crustaceans and cephalopods.  Females lay a single egg, which is then incubated by the male in a special pouch on top of the feet. Incubation lasts 62-67 days during which time the male fasts and the female returns to the sea to forage. It is this period when males and their eggs can be found fighting the harsh winter conditions and incubating their eggs in huddles. Because of their icy habitat, Emperor Penguins do not build a nest. When the chicks hatch they are covered in down and have a black head with 2 white spots near the eyes. If they hatch before the female returns to feed them, the males will regurgitate an esophageal secretion occasionally referred to as “penguin milk”. When the female returns to the breeding site, the male then returns to the sea to forage for several weeks. They lose up to 50% of their total body weight during the incubation period. Emperor Penguin chicks are fed regurgitated fish by the females during the male’s absence, then by both parents until they are ready to leave the breeding site at about 4 months.

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