Emperor Penguins

By Niesha Happell

Habitat

The habitat of an Emperor Penguin is limited to the Antartic and the surrounding seas, and unlike other species of penguins they can rarely be found anywhere else in the world (unless they are in captivity.) The Emperor Penguin is an aquatic bird this means it will only hunt in the ocean. It uses the Antarctic continent as a spot to breed as the young penguins need to grow and sturdy  before it can venture out into the ocean.

Fertilisation

Emperor penguins breed during the antarctic winter, June through
August. During their  breeding season temperatures can drop to -60 degrees Celsius.  Winds may reach 200 km per hour.

The Emperor Penguin is able to breed at around three years of age, and usually commences breeding around one to three years later. All Emperor Penguins travel to colonial nesting area, they often travel 50 - 120 km to get there. When the days begin to get shorter the penguins know that it is time to head inland and start breeding. Penguins are amniotes which means they lay eggs. In May or early June the female penguin lays one egg, about 460–470 g.  The egg is a pear-shaped, pale greenish-white egg. The egg about 12 cm long and 8 cm wide.

After laying, the mother's nutritional reserves are exhausted and she very carefully transfers the egg to the male, before immediately returning to the sea for two months to feed. Transferring the egg can be a hard task and many couple break the egg in the process and have to wait til next year to reproduce again. If the transfer is successful the male spends the winter incubating the egg in his pouch, balancing it on the tops of his feet, for 64 consecutive days until hatching, hatching may take as long as two or three days to complete, as the shell of the egg is thick. . To survive the cold the males huddle together, taking turns in the middle of the huddle. They have also been observed with their backs to the wind to conserve body heat.

The female penguin returns at any time from hatching to ten days afterwards, from mid-July to early August. She finds her mate among the hundreds of fathers by his vocal call and takes over caring for the chick, feeding it by regurgitating the food that she has stored in her stomach. The male then leaves to take his turn at sea, spending around 24 days there before returning. The parents then take turns, one while the other forages at sea.

Development

Emperor penguins develop in a very peculiar way. They are amniotes which means they the chicks develop in an egg. They develop externally which means the embryo develops outside the body. There are many advantages of this process such as the mother does not have to do all the work once she has laid the egg the father can help to keep it warm while the mother goes and feeds. Another advantage is that there is a greater chance of successful fertilization. There are also some disadvantages, such as when they egg is transfered there is a high risk of breaking it and many couples do. If the egg is broken they have to wait til next year to try again. Emperor penguins gestation period goes for about 63 days.

Parental care

A chick depends on its parents for survival between hatching and the growth of its waterproof feathers. This period may range from seven weeks for Adélie chicks to 13 months for king chicks. For most penguin species, once a chick has replaced its juvenile down with waterproof feathers it is able to enter the water and becomes independent of its parents. Juvenile Gentoo penguins that have undergone a complete moult, leave the colony to forage at sea during the day but return to the colony with some still receiving food from their parents for 25 to 35 days following the moult.

Chicks require caring parents to survive. Both Mum and Dad feed the chick regurgitated food which they take turns to go and collect. Parents can tell their chick apart from any other to make sure they are feeding the right one. The way to tell their chick apart from all the others is by their distinctive call.


Male emperor penguins exhibit a unique feature. If the chick hatches before the mother returns, the father, is able to produce a milky substance to feed the chick, so that they chick can survive for at least 2 weeks.

Parents keep their chick warm by covering them with their warm brood patch, which is basically warm fat.

Bibliography

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