Emperor penguin chicks on Snow Hill Island, Antarctica

The Emperor penguin Aptenodytes forsteri is one of only two species of penguin that inhabit the Antarctic continent: Adelie penguins breed there in summer, while Emperors breed in winter.

Emperors are the largest of all penguins, easily recognised by their black cap, blue-grey neck, orange ear-patches and bills and yellow breasts. There is a thick layer of blubber under the Emperor’s skin. In their chicks, it is covered by a dense layer of woolly down. An overlapping coat of feathers grows over this layer. The outer feathers are covered in a greasy waterproof coating. It’s mainly the layers of feathers that keep the water off the penguins’ skin and help retain heat. The feathers are highly specialised and modified compared to the feathers of flying birds. For example, they are smaller, stiff, and lanceolate. There are far more feathers on a penguin than on a flying bird of comparative size. The feathers of an adult have tufts of downy underfeathers attached to the bottom of the rachis (feather shaft). So down and main feather are all part of the same structure. Feathers are very complex structures made of keratin (same as our hair and finger nails) that is naturally water-repellent. What birds – and particularly penguins – need to do is keep their feathers in good condition so they remain supple and properly aligned . Only when feathers are aligned properly will they keep out the water. Birds have a gland, the preen gland, at the base of their tails that produces a very complex and chemically complicated preen oil. It is more like a conditioner for feathers than grease.

Emperor penguin Life Cycle

Emperor penguin Life Cycle

The Emperor penguin grows to around 115 cm. It weighs 25-40 kilograms, but male weight can vary by up to half that amount depending on the stage of the breeding cycle and how much body reserves he has laid down before the breeding season started.

Males and females are indistinguishable during most of the year. However, when it becomes time for the male to switch responsibilities with the female, the male can have slimmed down to half his weight. Over forty colonies are known, ranging in size from less than 200 pairs in the Dion Islands to over 50,000 pairs on Coulman Island. Perhaps 200,000 stable breeding pairs can be found on the Antarctic ice shelves. Some like Dion Island are doing extremely badly. Others like Coulman Island are probably doing alright but we don’t really know. The problem is that the only way to find out how many breeding pairs there are, it’s necessary to count the incubating males in winter (one male = one breeding pair). The trouble is that most colonies are so remote that nobody can get there to do the job.

The Emperor penguin feeds primarily on shoaling fish, small crustaceans and squid. They can dive more than 300 metres deep, and remain under water for as long as 22 minutes; but these are extremes. Most of the time, emperors are feeding down to around, say, 150-200 metres, particularly in winter. The majority of their dives last only 3-6 minutes.

Most Emperor penguin colonies are located on the fast ice, i.e. frozen sea-ice. That is not the same as an ice-shelf. Ice-shelves occur at the end of glacier as they are flowing into the ocean. Ice-shelves are freshwater ice. Only two colonies are known on land.

Emperor penguin chicks on Snow Hill Island, Antarctica

Emperor penguin chicks on Snow Hill Island, Antarctica

The female lays only one egg; it is too energetically expensive to rear more than one chick; and they can only fit one egg (and later one chick) onto their feet. Also, if an egg is lost, it cannot be relaid because by the time the female returns it is far too late to try again. The egg an Emperor penguin female lays is actually rather small. If a 28-kg female lays, say, a 465 g egg, that is less than 2% of her body mass. Compare this to two 125 g eggs laid by an Adelie penguin. That’s around 6.5% of a 3.8-kg female’s body mass (still small compared to the eggs Brown Kiwis produce!).

Emperors assemble at the breeding colonies early in winter, shortly after the sea ice has formed. They breed during the perpetual darkness of the Antarctic winter, gathering at rookeries up to 90 kilometers inland during the months of April and May.

Each Emperor, on returning from the north, first looks faithfully for his mate of the previous year. Unless that male or female has died, each penguin returns to the same partner. The Emperors go through a stage of courting before mating. A male may try to befriend a female who has not yet found her partner. If and when his true mate does arrive, the intruder leaves to find a different mate. Emperor pairs gather together near a solid iceberg to each lay a single egg. There are no special preparations or nest. Laying typically occurs in May or June at the start of the bitter Antarctic winter. The Emperors are believed to have developed this winter breeding pattern to allow the chick to grow to independence at a time when food is most plentiful.

After the female lays her egg, she passes it over to the male – though not quite immediately. Sometimes females sit on a newly-laid egg for hours before their mates finally get them: eggs are very precious commodities, and the changeover is a very hazardous transition. If the male does not manage to scoop up the egg very quickly, it freezes and the breeding season is over for a pair before it has really begun. So the females are not very keen to risk loosing their valuable egg. The female travels across the ice to feed in the fish-filled waters far away in the north. She spends the winter at sea.

The male Emperor fasts through the winter during incubation of the egg. Incubation is solely his responsibility. He positions the egg on top of his feet and covers it with a warm fold of feathered abdominal skin. The incubation lasts nearly two months. During the Antarctic winter, the period of darkness can last more than 20 hours. Huddling emperor penguins may spend most of a 24-hour period sleeping while they incubate eggs. Sleeping conserves energy while they fast.

Between mid-July and the beginning of August, the young are hatched. A freshly hatched emperor penguin chick weighs somewhere between 120 and 160 g and they are approximately 15 cm (6 inches) long. When the chicks finally emerge, they are very hungry. The females return to the colonies seven to eight weeks after laying to relieve their mates and tend the newly-hatched chicks. If the female hasn’t yet arrived, the father regurgitates a white secretion and feeds it to his chick. The chicks huddle together: the climate is extremely harsh. Winter temperatures may fall below -60C. Wind velocities can reach 180km per hour. But inside the huddles, the temperature can be as high as 20°C above ambient conditions. Adults recognize and feed only their own chicks. Parents are able to identify their young by their chick’s distinctive call. The contact call of emperor penguins can be heard up to a kilometer away.

Emperor Penguin, Melbourne Museum, Australia

Emperor Penguin, Melbourne Museum, Australia

Chicks grow slowly at first, more rapidly in late spring. Once the young are about seven weeks old, they join other chicks in a crèche, which is protected by a few adults. By midsummer, the fledglings are independent. They will be ready to breed in 4-8 years. Giant petrels prey upon chicks, whereas at sea their predators are orcas and leopard seals. Emperor penguins can live up to twenty years or more; exceptional cases have been recorded of over forty years, though such extremes of longevity are rare. Mortality among the chicks and fledglings is high, especially after after fledging in their first year of life when the young Emperors must figure out how to live at sea. The learning curve is steep, and inevitably many youngsters perish; but the survivors typically enjoy a long life.

Type of Penguin Species

  • Emperor Aptenodytes fosteri
  • King Aptenodytes patagonicus
  • Adelie Pygoscelis adeliae
  • Gentoo Pygoscelis papua
  • Chinstrap Pygoscelis antarctica
  • Fiordland Crested Eudyptes pachyrhynchus
  • Erect-crested Eudyptes sclateri
  • Rockhopper Eudyptes chrysocome
  • Macaroni Eudyptes chrysolophus
  • Royal Eudyptes schlegeli
  • Snares Island Eudyptes robustus
  • Yellow-eyed Megadyptes antipodes
  • Little, Little Blue, Fairy Eudyptula minor
  • Jackass, African Spheniscus demersus
  • Peruvian/Humboldt Spheniscus humboldti
  • Magellanic Spheniscus magellanicus
  • Galapagos Spheniscus mendiculus

Emperor Penguin Colony Struggling With Iceberg Blockade

The movements of two gigantic Antarctic icebergs appear to have dramatically reduced the number of Emperor penguins living and breeding in a colony at Cape Crozier, according to two researchers who visited the site last month.

The colony is one of the first ever visited by human beings early in the 20th century.

“It’s certain that the number of breeding birds is way down” from previous years, said Gerald Kooyman, a National Science Foundation-funded researcher at the Scripps Institution of Oceanography in La Jolla, Calif.

Kooyman took aerial photos of the colony in August during the flight missions that preceded the official start of the Antarctic research season. He returned to visit the colony in October, after the season was underway, with Paul Ponganis, another NSF-funded Emperor researcher who also is at Scripps.

The photographic evidence and the scientists’ observations on the ground, Kooyman said, indicate the colony has scattered into at least five subgroups. The disruption appears to be caused by grounding in the past two years of two enormous icebergs-B-15 and C-19-near Cape Crozier.

He said that two years ago the colony was home to approximately 2,400 adult Emperors and approximately 1,200 chicks. Aerial photographs showed the researchers the current distribution of the birds and the number of groups, but they did not provide details about the number of breeding birds and the conditions in the colony. Kooyman said the site visits confirm what the photographic evidence appeared to show: ice conditions produced by the collisions of the giant bergs with the shoreline forced the bird colony to break up into smaller subgroups and also indicated the numbers of chicks and breeding pairs is greatly reduced from previous years.

“The colony had been fragmented into at least five groups. I think that’s a habitat problem,” he said. “The habitat is disturbed from the previous years, and I think it stays that way.”

But, Kooyman said, his visit showed conditions for the birds are not as severe as he expected.

Emperor penguin chicks on Snow Hill Island, Antarctica

Emperor penguin chicks on Snow Hill Island, Antarctica

“I was expecting to see just about total failure,” he noted.

But a comparison with another Emperor colony at Beaufort Island, Kooyman said, also shows that the Crozier birds have been less successful finding food for their young.

“It looks like the development of the chicks has been slower than at Beaufort,” he said. “And development is related to food sources. It looks like they were not as well fed.”

He also said that shifts in the ice might have caused additional fatalities. “We could not find one group. It looks like they were in an ice canyon that was eliminated by two ice plates running together,” he said. As to the fate of the birds, “It’s a question of whether they got out of there or got crushed. It’s impossible for us to determine that.”

The Cape Crozier colony is noted in the history of Antarctic exploration. In 1911, three members of Robert Falcon Scott’s ill-fated South Pole expedition hauled a sledge 60 miles from Scott’s base at Cape Evans to Cape Crozier, on the far side of Ross Island, in complete darkness and sub-zero degree (F) temperatures, to acquire three unhatched Emperor egg from the colony. At the time, Emperors were thought to perhaps represent an evolutionary “missing link” between reptiles and birds.

Kooyman the recent survey of the colony was conducted in “very demanding” conditions almost exactly a century after that episode. Airlifted to the ice near the colony by helicopter, “we took three days in fine weather to traverse the entire area because the ice was so broken up.” The period of fine weather was followed by a summer storm.

Kooyman and Ponganis will compare notes on the health of the Emperor colony with David Ainley, an NSF-funded researcher who, as part of a long-term study on Adelie penguins, has been following the effects of the icebergs on Adelie colonies.

Emperor penguin chicks on Snow Hill Island, Antarctica

Emperor penguin chicks on Snow Hill Island, Antarctica

Ponganis noted that the icebergs causing the environmental change affecting the Emperor colony appear to be moving away from the area. But he added that the opportunity to study their effects on the birds adds to scientific knowledge of Emperors and their ability to adapt to change.

“It’s an incredible natural experiment as far as the physical effects on the colony and how they deal with it,” he said. “Crozier is a good test of all kinds of conditions that Emperors can deal with.”

Credits:
with many thanks to:
Barbara Wienecke, Phd
Seabird Ecologist
Department of Environment & Heritage
Australian Antarctic Division
203 Channel Highway
Kingston TASMANIA 7050

 

Emperor penguin chicks on Snow Hill Island, Antarcticahttp://i1.wp.com/plexusworld.com/wp-content/uploads/happy-feet_1732311i.jpg?fit=1024%2C1024http://i1.wp.com/plexusworld.com/wp-content/uploads/happy-feet_1732311i.jpg?resize=150%2C150 Damien Lucian WorldWildLife,,,,,,,,,,,
The Emperor penguin Aptenodytes forsteri is one of only two species of penguin that inhabit the Antarctic continent: Adelie penguins breed there in summer, while Emperors breed in winter. Emperors are the largest of all penguins, easily recognised by their black cap, blue-grey neck, orange ear-patches and bills and yellow...
<span style="font-family: verdana;"><span style="font-family: verdana;"><b>The Emperor penguin <i>Aptenodytes forsteri</i> is one of only two species of penguin that inhabit the Antarctic continent: Adelie penguins breed there in summer, while Emperors breed in winter.</b></span></span> Emperors are the largest of all penguins, easily recognised by their black cap, blue-grey neck, orange ear-patches and bills and yellow breasts. There is a thick layer of blubber under the Emperor's skin. In their chicks, it is covered by a dense layer of woolly down. An overlapping coat of feathers grows over this layer. The outer feathers are covered in a greasy waterproof coating. It's mainly the layers of feathers that keep the water off the penguins' skin and help retain heat. The feathers are highly specialised and modified compared to the feathers of flying birds. For example, they are smaller, stiff, and lanceolate. There are far more feathers on a penguin than on a flying bird of comparative size. The feathers of an adult have tufts of downy underfeathers attached to the bottom of the rachis (feather shaft). So down and main feather are all part of the same structure. Feathers are very complex structures made of keratin (same as our hair and finger nails) that is naturally water-repellent. What birds - and particularly penguins - need to do is keep their feathers in good condition so they remain supple and properly aligned . Only when feathers are aligned properly will they keep out the water. Birds have a gland, the preen gland, at the base of their tails that produces a very complex and chemically complicated preen oil. It is more like a conditioner for feathers than grease. The <strong>Emperor penguin</strong> grows to around 115 cm. It weighs 25-40 kilograms, but male weight can vary by up to half that amount depending on the stage of the breeding cycle and how much body reserves he has laid down before the breeding season started. Males and females are indistinguishable during most of the year. However, when it becomes time for the male to switch responsibilities with the female, the male can have slimmed down to half his weight. Over forty colonies are known, ranging in size from less than 200 pairs in the Dion Islands to over 50,000 pairs on Coulman Island. Perhaps 200,000 stable breeding pairs can be found on the Antarctic ice shelves. Some like Dion Island are doing extremely badly. Others like Coulman Island are probably doing alright but we don't really know. The problem is that the only way to find out how many breeding pairs there are, it's necessary to count the incubating males in winter (one male = one breeding pair). The trouble is that most colonies are so remote that nobody can get there to do the job. The <strong>Emperor penguin</strong> feeds primarily on shoaling fish, small crustaceans and squid. They can dive more than 300 metres deep, and remain under water for as long as 22 minutes; but these are extremes. Most of the time, emperors are feeding down to around, say, 150-200 metres, particularly in winter. The majority of their dives last only 3-6 minutes. Most <strong>Emperor penguin</strong> colonies are located on the fast ice, i.e. frozen sea-ice. That is not the same as an ice-shelf. Ice-shelves occur at the end of glacier as they are flowing into the ocean. Ice-shelves are freshwater ice. Only two colonies are known on land. The female lays only one egg; it is too energetically expensive to rear more than one chick; and they can only fit one egg (and later one chick) onto their feet. Also, if an egg is lost, it cannot be relaid because by the time the female returns it is far too late to try again. The egg an <strong>Emperor penguin female</strong> lays is actually rather small. If a 28-kg female lays, say, a 465 g egg, that is less than 2% of her body mass. Compare this to two 125 g eggs laid by an Adelie penguin. That's around 6.5% of a 3.8-kg female's body mass (still small compared to the eggs Brown Kiwis produce!). Emperors assemble at the breeding colonies early in winter, shortly after the sea ice has formed. They breed during the perpetual darkness of the Antarctic winter, gathering at rookeries up to 90 kilometers inland during the months of April and May. Each Emperor, on returning from the north, first looks faithfully for his mate of the previous year. Unless that male or female has died, each penguin returns to the same partner. The Emperors go through a stage of courting before mating. A male may try to befriend a female who has not yet found her partner. If and when his true mate does arrive, the intruder leaves to find a different mate. Emperor pairs gather together near a solid iceberg to each lay a single egg. There are no special preparations or nest. Laying typically occurs in May or June at the start of the bitter Antarctic winter. The Emperors are believed to have developed this winter breeding pattern to allow the chick to grow to independence at a time when food is most plentiful. After the female lays her egg, she passes it over to the male - though not quite immediately. Sometimes females sit on a newly-laid egg for hours before their mates finally get them: eggs are very precious commodities, and the changeover is a very hazardous transition. If the male does not manage to scoop up the egg very quickly, it freezes and the breeding season is over for a pair before it has really begun. So the females are not very keen to risk loosing their valuable egg. The female travels across the ice to feed in the fish-filled waters far away in the north. She spends the winter at sea. The male Emperor fasts through the winter during incubation of the egg. Incubation is solely his responsibility. He positions the egg on top of his feet and covers it with a warm fold of feathered abdominal skin. The incubation lasts nearly two months. During the Antarctic winter, the period of darkness can last more than 20 hours. Huddling <strong>emperor penguins</strong> may spend most of a 24-hour period sleeping while they incubate eggs. Sleeping conserves energy while they fast. Between mid-July and the beginning of August, the young are hatched. A freshly hatched <strong>emperor penguin chick</strong> weighs somewhere between 120 and 160 g and they are approximately 15 cm (6 inches) long. When the chicks finally emerge, they are very hungry. The females return to the colonies seven to eight weeks after laying to relieve their mates and tend the newly-hatched chicks. If the female hasn't yet arrived, the father regurgitates a white secretion and feeds it to his chick. The chicks huddle together: the climate is extremely harsh. Winter temperatures may fall below -60C. Wind velocities can reach 180km per hour. But inside the huddles, the temperature can be as high as 20°C above ambient conditions. Adults recognize and feed only their own chicks. Parents are able to identify their young by their chick's distinctive call. The contact call of <strong>emperor penguins</strong> can be heard up to a kilometer away. Chicks grow slowly at first, more rapidly in late spring. Once the young are about seven weeks old, they join other chicks in a crèche, which is protected by a few adults. By midsummer, the fledglings are independent. They will be ready to breed in 4-8 years. Giant petrels prey upon chicks, whereas at sea their predators are orcas and leopard seals. <strong>Emperor penguins</strong> can live up to twenty years or more; exceptional cases have been recorded of over forty years, though such extremes of longevity are rare. Mortality among the chicks and fledglings is high, especially after after fledging in their first year of life when the young Emperors must figure out how to live at sea. The learning curve is steep, and inevitably many youngsters perish; but the survivors typically enjoy a long life. <h2>Type of Penguin Species</h2> <ul> <li>Emperor <i>Aptenodytes fosteri</i></li> <li>King <i>Aptenodytes patagonicus</i></li> <li>Adelie <i>Pygoscelis adeliae</i></li> <li>Gentoo <i>Pygoscelis papua</i></li> <li>Chinstrap <i>Pygoscelis antarctica </i></li> <li>Fiordland Crested <i>Eudyptes pachyrhynchus</i></li> <li>Erect-crested <i>Eudyptes sclateri</i></li> <li>Rockhopper<i> Eudyptes chrysocome</i></li> <li>Macaroni <i>Eudyptes chrysolophus</i></li> <li>Royal <i>Eudyptes schlegeli</i></li> <li>Snares Island <i>Eudyptes robustus </i></li> <li>Yellow-eyed <i>Megadyptes antipodes</i></li> <li>Little, Little Blue, <i>Fairy Eudyptula minor</i></li> <li>Jackass, African <i>Spheniscus demersus</i></li> <li>Peruvian/Humboldt <i>Spheniscus humboldti</i></li> <li>Magellanic <i>Spheniscus magellanicus</i></li> <li>Galapagos <i>Spheniscus mendiculus</i></li> </ul> <h2>Emperor Penguin Colony Struggling With Iceberg Blockade</h2> <span style="font-family: verdana,arial,helvetica;"><span style="font-family: verdana,arial,helvetica;">The movements of two gigantic Antarctic icebergs appear to have dramatically reduced the number of <strong>Emperor penguins</strong> living and breeding in a colony at Cape Crozier, according to two researchers who visited the site last month.</span></span> The colony is one of the first ever visited by human beings early in the 20th century. "It's certain that the number of breeding birds is way down" from previous years, said Gerald Kooyman, a National Science Foundation-funded researcher at the Scripps Institution of Oceanography in La Jolla, Calif. Kooyman took aerial photos of the colony in August during the flight missions that preceded the official start of the Antarctic research season. He returned to visit the colony in October, after the season was underway, with Paul Ponganis, another NSF-funded Emperor researcher who also is at Scripps. The photographic evidence and the scientists' observations on the ground, Kooyman said, indicate the colony has scattered into at least five subgroups. The disruption appears to be caused by grounding in the past two years of two enormous icebergs-B-15 and C-19-near Cape Crozier. He said that two years ago the colony was home to approximately 2,400 adult Emperors and approximately 1,200 chicks. Aerial photographs showed the researchers the current distribution of the birds and the number of groups, but they did not provide details about the number of breeding birds and the conditions in the colony. Kooyman said the site visits confirm what the photographic evidence appeared to show: ice conditions produced by the collisions of the giant bergs with the shoreline forced the bird colony to break up into smaller subgroups and also indicated the numbers of chicks and breeding pairs is greatly reduced from previous years. "The colony had been fragmented into at least five groups. I think that's a habitat problem," he said. "The habitat is disturbed from the previous years, and I think it stays that way." But, Kooyman said, his visit showed conditions for the birds are not as severe as he expected. "I was expecting to see just about total failure," he noted. But a comparison with another Emperor colony at Beaufort Island, Kooyman said, also shows that the Crozier birds have been less successful finding food for their young. "It looks like the development of the chicks has been slower than at Beaufort," he said. "And development is related to food sources. It looks like they were not as well fed." He also said that shifts in the ice might have caused additional fatalities. "We could not find one group. It looks like they were in an ice canyon that was eliminated by two ice plates running together," he said. As to the fate of the birds, "It's a question of whether they got out of there or got crushed. It's impossible for us to determine that." The Cape Crozier colony is noted in the history of Antarctic exploration. In 1911, three members of Robert Falcon Scott's ill-fated South Pole expedition hauled a sledge 60 miles from Scott's base at Cape Evans to Cape Crozier, on the far side of Ross Island, in complete darkness and sub-zero degree (F) temperatures, to acquire three unhatched Emperor egg from the colony. At the time, Emperors were thought to perhaps represent an evolutionary "missing link" between reptiles and birds. Kooyman the recent survey of the colony was conducted in "very demanding" conditions almost exactly a century after that episode. Airlifted to the ice near the colony by helicopter, "we took three days in fine weather to traverse the entire area because the ice was so broken up." The period of fine weather was followed by a summer storm. Kooyman and Ponganis will compare notes on the health of the Emperor colony with David Ainley, an NSF-funded researcher who, as part of a long-term study on Adelie penguins, has been following the effects of the icebergs on Adelie colonies. Ponganis noted that the icebergs causing the environmental change affecting the Emperor colony appear to be moving away from the area. But he added that the opportunity to study their effects on the birds adds to scientific knowledge of Emperors and their ability to adapt to change. "It's an incredible natural experiment as far as the physical effects on the colony and how they deal with it," he said. "Crozier is a good test of all kinds of conditions that Emperors can deal with." <address><strong>Credits:</strong></address><address><span style="font-family: verdana;">with many thanks to: </span></address><address><span style="font-family: verdana;">Barbara Wienecke, Phd Seabird Ecologist Department of Environment & Heritage Australian Antarctic Division 203 Channel Highway Kingston TASMANIA 7050</span></address>