Emperor penguins are only found only in the southern hemisphere and population concentrations are found in Dronning Maud Land, Princess Elizabeth Islands, the Ross Sea and Weddell Sea.
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Emperor Penguins - Author
Christopher Michel
Creative Commons Attribution 2.0 Generic license.
Surviving the Cold
They form large colonies which have complex social interactions. Emperors communicate vocally using unique sounds and varying frequencies to help parents and young penguins to recognise and communicate with each other.
Their physiology has evolved to allow them to survive days on the open pack ice and swim and hunt in the perishing cold waters of the Antarctic Ocean. They have around 70 feathers per square inch which form a dense insulating coat to help protect from the cold.
Their bones are solid and they have developed the ability to operate at levels with low oxygen and can slow down their metabolism, even shutting down non-essential body functions for periods without coming to harm.
They cooperate socially by huddling together in a group to escape the wind chill and conserve warmth. The ones in the centre of the group are the warmest and most protected whereas those on the perimeters are exposed to the wind and cold.
To compensate for this emperors take turns moving between the protected centre and on the exposed perimeter. This prevents individuals from over exposure to cold conditions and enhances the chances of group and individual survival.
With long cold winters spent living and even breeding on open ice such cooperation is necessary. They have also been observed cooperating while hunting.
Breeding
Penguins breed in the winter and females lay a single egg and then abandon it leaving the males alone to incubate it. The females then spend the next two months hunting, squid, krill and fish often needing to travel some 50 miles to reach the open ocean, depending on the ice conditions.
Though comical and ungainly on land in the sea emperor penguins are in their element. They can dive deeper than any other bird reaching depths of 1,850 feet and staying submerged for longer than 20 minutes.
Hatching
While the females hunt and eat the males keeps the egg warm. Unlike other birds emperors do not incubate their eggs by sitting on it. Male emperors have a brood pouch, as do females, which is a feathery skin. The egg is balanced on the male's feet and the pouch is used to cover it over and keep it warm. For the next two months the males have no food and are vulnerable to the harsh, unforgiving Antarctic weather while they await the return of the females.
When the females eventually return with full bellies they feed the hatched chicks by regurgitation. This leaves the males free to return to the sea to hunt for food for themselves. The females then protect the chicks with their own brood pouches keeping them warm and safe. A chick would last only a couple of minutes outside of this protective pouch.
Summer
The Antarctic summer begins in December and as the environment gradually warms the pack ice begins breaking up near the breeding site. The young emperors are now grown enough to swim and now have access to the ocean where they can fish independently.
Despite its isolated location the emperor penguin does have predators. Its enemies are leopard seals, walrus, and killer whales.
References, Attributions and Further Reading
Image: File:Emperor Penguins (11240188915).jpg - From Wikimedia Commons - Emperor Penguins - AuthorChristopher Michel - Creative Commons Attribution 2.0 Generic license.
Green Packs, 15 Interesting Facts About the Emperor PenguinNational Geographic, Emperor penguins
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