# Emperor penguin

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{{Short description|Large flightless seabird endemic to Antarctica}}
{{Use Oxford spelling|date=April 2026}}
{{About|the bird|the band|Emperor Penguin (band)}}
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{{Use dmy dates|date=April 2026}}
{{speciesbox
 | name                = Emperor penguin
 | status              = EN
 | status_system       = IUCN3.1
 | status_ref          = <ref name="IUCN2026"/>
 | image               = Aptenodytes forsteri -Snow Hill Island, Antarctica -adults and juvenile-8.jpg
 | image_caption       = Adults with a chick on [Snow Hill Island](/source/Snow_Hill_Island), Antarctic Peninsula
 | genus               = Aptenodytes
 | species             = forsteri
 | authority           = [Gray](/source/George_Robert_Gray), 1844
 | range_map           =
 | range_map_caption   =
}}

The '''emperor penguin''' ('''''Aptenodytes forsteri''''') is the tallest and heaviest of all living [penguin](/source/penguin) species and [lives exclusively](/source/Endemism) in [Antarctica](/source/Antarctica). The male and female are similar in [plumage](/source/plumage) and size, reaching {{cvt|100|cm}} in length and weighing from {{cvt|22|to|45|kg}}. Feathers of the head and back are black and sharply delineated from the white belly, pale-yellow breast and bright-yellow ear patches.

Like all species of penguin, the emperor is flightless, with a streamlined body, and wings stiffened and flattened into flippers for a marine [habitat](/source/habitat). Its diet consists primarily of [fish](/source/fish), but also includes [crustacean](/source/crustacean)s, such as [krill](/source/krill), and [cephalopod](/source/cephalopod)s, such as [squid](/source/squid). While hunting, the species can remain submerged around 20 minutes, diving to a depth of {{cvt|535|m}}. It has several adaptations to facilitate this, including an unusually structured [haemoglobin](/source/Hemoglobin) to allow it to function at low oxygen levels, solid bones that reduce [barotrauma](/source/barotrauma), and the ability to reduce its [metabolism](/source/metabolism) and shut down non-essential organ functions.

The only penguin species that breeds during the Antarctic winter, emperor penguins trek {{cvt|50|–|120|km}} over the ice to [breeding colonies](/source/seabird_colony) which can contain up to several thousand individuals. The female lays a single egg, which is [incubated](/source/Egg_incubation) for just over two months by the male while the female returns to the sea to feed; parents subsequently take turns foraging at sea and caring for their chick in the colony. The lifespan of an emperor penguin is typically 20 years in the wild, although observations suggest that some individuals may live as long as 50 years.

==Taxonomy==
Emperor penguins were [described](/source/species_description) in 1844 by English zoologist [George Robert Gray](/source/George_Robert_Gray), who created the [generic name](/source/Genus) from [Ancient Greek](/source/Ancient_Greek) word elements, {{Lang|grc|ἀ-πτηνο-δύτης}} [{{Lang|grc-Latn|a-ptēno-dytēs}}], "without-wings-diver". Its [specific name](/source/specific_name_(zoology)) is in honour of the German naturalist [Johann Reinhold Forster](/source/Johann_Reinhold_Forster), who accompanied Captain [James Cook](/source/James_Cook) on his [second voyage](/source/Second_voyage_of_James_Cook) and officially named five other penguin species.<ref>{{cite web|author=British Museum|title=King penguin: The Forsters, King and Emperor|url=https://www.britishmuseum.org/explore/highlights/highlight_objects/loan_in/k/king_penguin.aspx|access-date=28 July 2013|work=Explore/Highlights|publisher=Trustees of the British Museum|archive-url=https://web.archive.org/web/20080805043046/https://www.britishmuseum.org/explore/highlights/highlight_objects/loan_in/k/king_penguin.aspx|archive-date=5 August 2008}}</ref> Forster may have been the first person to see emperor penguins in 1773–74, when he recorded a sighting of what he believed was the similar [king penguin](/source/king_penguin) (''A. patagonicus'') but, given the location, may very well have been the emperor penguin (''A. forsteri'').<ref name="Wienecke">{{Cite journal | last1 = Wienecke | first1 = B. | title = The history of the discovery of emperor penguin colonies, 1902–2004 | doi = 10.1017/S0032247409990283 | journal = Polar Record | volume = 46 | issue = 3 | pages = 271–276 | year = 2009 | s2cid = 129641322 }}</ref>

Together with the king penguin, the emperor penguin is one of two extant species in the genus ''[Aptenodytes](/source/Aptenodytes)''. [Fossil](/source/Fossil) evidence of a third species—[Ridgen's penguin](/source/Ridgen's_penguin) (''A. ridgeni'')—has been found from the late [Pliocene](/source/Pliocene), about three million years ago, in New Zealand.{{sfn|Williams|1995|p=13}} Studies of penguin behaviour and genetics have proposed that the genus ''Aptenodytes'' is [basal](/source/Basal_(phylogenetics)); in other words, that it split off from a branch which led to all other living penguin species.<ref>{{cite journal|author=Jouventin P|year=1982|title=Visual and vocal signals in penguins, their evolution and adaptive characters|journal=Advances in Ethology|volume=24|pages=1–149|isbn=978-3-48-961436-4|oclc=8378191}}</ref> [Mitochondrial](/source/Mitochondrial_DNA) and [nuclear](/source/Nuclear_DNA) DNA evidence suggests this split occurred around 40&nbsp;million years ago.<ref>{{cite journal|vauthors=Baker AJ, Pereira SL, Haddrath OP, Edge KA |year=2006|title=Multiple gene evidence for expansion of extant penguins out of Antarctica due to global cooling|journal=Proc Biol Sci|volume=273|issue=1582|pages=11–17|doi=10.1098/rspb.2005.3260|pmid=16519228|pmc=1560011}}</ref>

==Description==
thumb|Adults with chicks|left

Adult emperor penguins are {{cvt|110|-|120|cm}} in length, averaging {{cvt|115|cm}}.<ref>Stonehouse, B. (1975) "Introduction: the Spheniscidae". In: Stonehouse, B. (ed) ''The Biology of Penguins'', pp. 1–14, London: Macmillan, cited in {{harvnb|Ksepka|Fordyce|Ando|Jones|2012}}</ref> Due to the method of [bird measurement](/source/bird_measurement) that measures length between bill to tail, sometimes body length and standing height are confused, and some reported height even reaching {{cvt|1.5|m}} tall.<ref name="Ksepka-2012">{{Cite journal |last1=Ksepka |first1=Daniel T. |last2=Fordyce |first2=R. Ewan |last3=Ando |first3=Tatsuro |last4=Jones |first4=Craig M. |date=1 March 2012 |title=New fossil penguins (Aves, Sphenisciformes) from the Oligocene of New Zealand reveal the skeletal plan of stem penguins |url=https://www.tandfonline.com/doi/full/10.1080/02724634.2012.652051 |journal=Journal of Vertebrate Paleontology |volume=32 |issue=2 |pages=235–254 |doi=10.1080/02724634.2012.652051 |bibcode=2012JVPal..32..235K |s2cid=85887012 |issn=0272-4634|url-access=subscription }}</ref> There are still more than a few papers mentioning that they reach a standing height of {{cvt|1.2|m}} instead of body length.<ref>{{Cite journal |last1=Gilbert |first1=Caroline |last2=Blanc |first2=Stéphane |last3=Le Maho |first3=Yvon |last4=Ancel |first4=André |date=1 January 2008 |title=Energy saving processes in huddling emperor penguins: from experiments to theory |journal=Journal of Experimental Biology |volume=211 |issue=1 |pages=1–8 |doi=10.1242/jeb.005785 |pmid=18083725 |bibcode=2008JExpB.211....1G |s2cid=23176358 |issn=1477-9145}}</ref><ref>{{Cite journal |last1=Davenport |first1=J |last2=Hughes |first2=RN |last3=Shorten |first3=M |last4=Larsen |first4=PS |date=26 May 2011 |title=Drag reduction by air release promotes fast ascent in jumping emperor penguins—a novel hypothesis |journal=Marine Ecology Progress Series |volume=430 |pages=171–182 |doi=10.3354/meps08868 |bibcode=2011MEPS..430..171D |issn=0171-8630|doi-access=free |hdl=10468/8867 |hdl-access=free }}</ref> Although standing height of emperor penguin is rarely provided at scientific reports, Prévost (1961)<ref>Prévost , J. (1961) ''Écologie du Manchot Empereur'', p. 204, Paris: Hermann, cited in {{harvnb|Ksepka|Fordyce|Ando|Jones|2012}}</ref> recorded 86 wild individuals and measured maximum height of {{cvt|1.08|m}}. Friedman (1945)<ref>Friedmann, H. (1945) "Birds of the United States Antarctic Service Expedition 1939–1941", ''Proceedings of the American Philosophical Society'', 89: 205–313, cited in {{harvnb|Ksepka|Fordyce|Ando|Jones|2012}}</ref> recorded measurements from 22 wild individuals and resulted height ranging {{cvt|83|-|97|cm}}. Ksepka ''et al''. (2012) measured standing height of {{cvt|81|-|94|cm}} according to 11 complete skins collected in [American Museum of Natural History](/source/American_Museum_of_Natural_History).<ref name="Ksepka-2012" /> The weight ranges from {{cvt|22.7|to|45.4|kg}} and varies by sex, with males [weighing more than](/source/sexual_dimorphism) females. It is the fifth heaviest living bird species, after only the larger varieties of [ratite](/source/ratite).<ref name = "CRC">''CRC Handbook of Avian Body Masses'' by John B. Dunning Jr. (Editor). CRC Press (1992), {{ISBN|978-0-8493-4258-5}}.</ref> The weight also varies by season, as both male and female penguins lose substantial mass while raising hatchlings and [incubating](/source/avian_incubation) their egg. Male emperor penguins must withstand the extreme Antarctic winter cold for more than two months while protecting their eggs; eating nothing during this time, male emperors will lose around {{cvt|12|kg}} while waiting for their eggs to hatch.<ref>{{cite web |url=http://www2.canada.com/calgaryherald/news/story.html?id=59132c88-d1ec-434c-b16f-d15eb1ceb16b&p=2 |title=Daddy Dearest |publisher=.canada.com |date=19 June 1910 |access-date=21 November 2012 |archive-url=https://web.archive.org/web/20120612044933/http://www2.canada.com/calgaryherald/news/story.html?id=59132c88-d1ec-434c-b16f-d15eb1ceb16b&p=2 |archive-date=12 June 2012}}</ref> Adult birds weigh between {{cvt|25|kg}} and {{cvt|45|kg}}, with weights dropping through the breeding season. Females typically weigh {{cvt|18|kg}} less than males.<ref name="ADW">{{cite web |url= https://animaldiversity.org/accounts/Aptenodytes_forsteri/ |title= Aptenodytes forsteri |author= Sarah Wilber |date=  |page= |publisher= University of Michigan |access-date= 9 March 2026 |url-status=live |archive-url= https://web.archive.org/web/20260309015919/https://animaldiversity.org/accounts/Aptenodytes_forsteri/|archive-date= 9 March 2026 }}</ref>
[[File:2007 Snow-Hill-Island Luyten-De-Hauwere-Emperor-Penguin-59.jpg|thumb|Adult with chick, at [Snow Hill Island](/source/Snow_Hill_Island)]]
Like all penguin species, emperor penguins have streamlined bodies to minimize drag while swimming, and wings that are more like stiff, flat flippers.{{sfn|Williams|1995|p=3}} The tongue is equipped with rear-facing barbs to prevent prey from escaping when caught.<ref name=NG04/> Males and females are similar in size and colouration.<ref name= "ADW"/> The adult has deep black [dorsal](/source/Dorsum_(biology)) feathers, covering the head, chin, throat, back, dorsal part of the flippers, and tail. The black plumage is sharply delineated from the light-coloured plumage elsewhere. The underparts of the wings and belly are white, becoming pale yellow in the upper breast, while the ear patches are bright yellow. The upper mandible of the {{cvt|8|cm}} long bill is black, and the lower mandible can be pink, orange or lilac.{{sfn|Williams|1995|p=152}} In juveniles, the [auricular](/source/Ear) patches, chin and throat are white, while its bill is black.{{sfn|Williams|1995|p=152}} Emperor penguin chicks are typically covered with silver-grey [down](/source/down_feather) and have black heads and white masks.{{sfn|Williams|1995|p=152}} A chick with all-white plumage was seen in 2001, but was not considered to be an [albino](/source/Albinism_in_biology) as it did not have pink eyes.<ref>{{cite web|url=http://www.cdnn.info/eco/e010908/e010908.html |title=Scientists find rare all-white emperor penguin |publisher=Cyber Diver News Network |work=CDNN |date=8 September 2001 |access-date=29 March 2008 |author=CDNN |archive-url=https://web.archive.org/web/20121107005517/http://www.cdnn.info/eco/e010908/e010908.html |archive-date=7 November 2012 }}</ref> Chicks weigh around {{cvt|315|g}} after hatching, and [fledge](/source/fledge) when they reach about 50% of adult weight.<ref name=Will159/>

The emperor penguin's dark plumage fades to brown from November until February (the Antarctic summer), before the yearly [moult](/source/moult) in January and February.{{sfn|Williams|1995|p=152}} Moulting is rapid in this species compared with other birds, taking only around 34&nbsp;days. Emperor penguin feathers emerge from the skin after they have grown to a third of their total length, and before old feathers are lost, to help reduce heat loss. New feathers then push out the old ones before finishing their growth.<ref name=Will45>{{Harvnb|Williams|1995|p=45}}.</ref>

The average yearly survival rate of an adult emperor penguin has been measured at 95.1%, with an average life expectancy of 19.9&nbsp;years. The same researchers estimated that 1% of emperor penguins hatched could feasibly reach an age of 50&nbsp;years.<ref name=Mougvanb79>{{cite journal|vauthors=Mougin JL, van Beveren M |year=1979|title=Structure et dynamique de la population de manchots empereur ''Aptenodytes forsteri'' de la colonie de l'archipel de Pointe Géologie, Terre Adélie|journal=[Comptes rendus de l'Académie des sciences](/source/Comptes_rendus_de_l'Acad%C3%A9mie_des_sciences)|volume=289D|pages=157–60|language=fr}}</ref> In contrast, only 19% of chicks survive their first year of life.<ref name=Will47>{{Harvnb|Williams|1995|p=47}}.</ref> Therefore, 80% of the emperor penguin population comprises adults five years and older.<ref name=Mougvanb79/>

===Vocalization===
thumb|alt=a family of emperor penguins in Antarctica|Emperor penguins and chick vocalizing in Antarctica

As the species has no fixed nesting sites that individuals can use to locate their own partner or chick, emperor penguins must rely on vocal sounds alone for identification.<ref name=Will68>{{Harvnb|Williams|1995|p=68}}.</ref> They use a complex set of calls that are critical to individual recognition between mates, parents and offspring,<ref name="ADW"/> displaying the widest variation in individual calls of all penguin species.<ref name=Will68/> Vocalizing emperor penguins use two [frequency band](/source/frequency_band)s simultaneously.<ref>{{cite journal | author = Robisson P | year = 1992 | title = Vocalizations in ''Aptenodytes'' Penguins: Application of the Two-voice Theory | url =http://sora.unm.edu/sites/default/files/journals/auk/v109n03/p0654-p0658.pdf | journal = [Auk](/source/The_Auk) | volume = 109 | issue = 3| pages = 654–658 }}</ref> Chicks use a frequency-modulated whistle to beg for food and to contact parents.<ref name="ADW"/>

===Adaptations to cold===
The emperor penguin breeds in the coldest environment of any bird species; air temperatures may reach {{cvt|-40|°C}}, and wind speeds may reach {{cvt|144|km/h}}. Water temperature is a frigid {{cvt|-1.8|°C}}, which is much lower than the emperor penguin's average body temperature of {{cvt|39|°C}}. The species has adapted in several ways to counteract heat loss.<ref name=Will107>{{Harvnb|Williams|1995|p=107}}.</ref> Dense feathers provide 80–90% of its insulation, and it has a layer of sub-[dermal](/source/dermal) fat which may be up to {{cvt|3|cm}} thick before breeding.<ref name=Will108>{{Harvnb|Williams|1995|p=108}}.</ref> While the density of contour feathers is approximately 9 per square centimetre (58 per square inch), a combination of dense afterfeathers and [down feather](/source/down_feather)s (plumules) likely play a critical role for insulation.<ref name=LATimesKhan>{{cite web|url=http://www.latimes.com/science/sciencenow/la-sci-sn-emperor-penguin-feathers-20151020-story.html|title=Emperor penguins' feathers defy conventional wisdom, study finds|access-date=21 October 2015|author=Khan A|date=20 October 2015|work=Los Angeles Times}}</ref><ref name=PRSBWilliams>{{cite journal|vauthors=Cassondra WL, Hagelin JC, Kooyman GL |year=2015|title=Hidden keys to survival: the type, density, pattern and functional role of emperor penguin body feathers|journal=Proceedings of the Royal Society B|volume=282|issue=1817|pages=2015–2033 |doi=10.1098/rspb.2015.2033|pmid=26490794|pmc=4633883}}</ref> Muscles allow the feathers to be held erect on land, reducing heat loss by trapping a layer of air next to the skin. Conversely, the plumage is flattened in water, thus waterproofing the skin and the downy underlayer.<ref name=Will10708>{{Harvnb|Williams|1995|pp=107–108}}.</ref> Preening is vital in facilitating insulation and in keeping the plumage oily and water-repellent.<ref name=Kooy90Heat>{{cite journal|vauthors=Kooyman GL, Gentry RL, Bergman WP, Hammel HT |year=1976|title= Heat loss in penguins during immersion and compression|journal=Comparative Biochemistry and Physiology|volume=54A|pages=75–80|pmid=3348|doi=10.1016/S0300-9629(76)80074-6|issue=1}}</ref>

The emperor penguin is able to [thermoregulate](/source/Thermoregulation) (maintain its core body temperature) without altering its metabolism, over a wide range of temperatures. Known as the thermoneutral range, this extends from {{cvt|-10|to|20|°C}}. Below this temperature range, its metabolic rate increases significantly, although an individual can maintain its [core temperature](/source/core_temperature) from {{cvt|38.0|°C}} down to {{cvt|-47|°C}}.<ref name=Will109>{{Harvnb|Williams|1995|p=109}}.</ref> Movement by swimming, walking, and shivering are three mechanisms for increasing metabolism; a fourth process involves an increase in the breakdown of fats by enzymes, which is induced by the hormone [glucagon](/source/glucagon).<ref name=Will110>{{Harvnb|Williams|1995|p=110}}.</ref> At temperatures above {{cvt|20|°C}}, an emperor penguin may become stressed as its body temperature and metabolic rate rise. In such cases the penguin may try to increase heat loss through respiration and raising its wings to increases the exposure of its body surface to the air.<ref name=Will111>{{Harvnb|Williams|1995|p=111}}.</ref>

===Adaptations to pressure and low oxygen===
[[File:Aptenodytes forsteri (1).jpg|thumb|Mounted skeleton at the [American Museum of Natural History](/source/American_Museum_of_Natural_History)]]
In addition to the cold, the emperor penguin encounters another stressful condition on deep dives—markedly increased pressure of up to 40 times that of the surface, which in most other terrestrial organisms would cause [barotrauma](/source/barotrauma). The bones of the penguin are solid rather than air-filled,<ref>{{cite web|url=http://news.nationalgeographic.com/news/2004/03/0329_040329_TVpenguins.html|archive-url=https://web.archive.org/web/20040603052124/http://news.nationalgeographic.com/news/2004/03/0329_040329_TVpenguins.html|archive-date=3 June 2004|title=Emperor Penguins: Uniquely Armed for Antarctica|publisher=National Geographic}}</ref> which eliminates the risk of mechanical barotrauma.

While diving, the emperor penguin's oxygen use is markedly reduced, as its heart rate is reduced to as low as 15–20 beats per minute and non-essential organs are shut down, thus facilitating longer dives.<ref name=NG04>{{cite web|url=http://news.nationalgeographic.com/news/2004/01/0130_040130_penguincam.html|title="Penguin Ranch" Reveals Hunting, Swimming Secrets|access-date=26 March 2008|author=Owen J|date=30 January 2004|work=National Geographic website|publisher=National Geographic|archive-url=https://web.archive.org/web/20071111202157/http://news.nationalgeographic.com/news/2004/01/0130_040130_penguincam.html|archive-date=11 November 2007}}</ref> Its [haemoglobin](/source/haemoglobin) and [myoglobin](/source/myoglobin) are able to bind and transport oxygen at low blood concentrations; this allows the bird to function with very low oxygen levels that would otherwise result in loss of consciousness.<ref>{{cite web|url=http://news.nationalgeographic.com/news/2007/12/071207-penguins-dive.html|title=Penguins Safely Lower Oxygen to "Blackout" Levels|access-date=26 March 2008|author=Norris S|date=7 December 2007|work=National Geographic website|publisher=National Geographic|archive-url=https://web.archive.org/web/20071208214357/http://news.nationalgeographic.com/news/2007/12/071207-penguins-dive.html|archive-date=8 December 2007}}</ref>

==Distribution and habitat==
thumb|right|Emperor penguin jumping out of the water in Antarctica
The emperor penguin has a circumpolar distribution in the Antarctic almost exclusively between the [66°](/source/66th_parallel_south) and [77°](/source/77th_parallel_south) south latitudes. It almost always breeds on stable pack ice near the coast and up to {{cvt|18|km}} offshore.<ref name="ADW" /> Breeding colonies are usually in areas where ice cliffs and icebergs provide some protection from the wind.<ref name="ADW"/> Three land colonies have been reported: one (now disappeared) on a shingle spit at the [Dion Islands](/source/Dion_Islands) on the [Antarctic Peninsula](/source/Antarctic_Peninsula),<ref>{{cite journal|last=Stonehouse|first=B|year=1953|title=The Emperor Penguin ''Aptenodytes forsteri'' Gray I. Breeding behaviour and development|journal=Falkland Islands Dependencies Survey Scientific Report|volume=6|pages=1–33}}</ref> one on a headland at [Taylor Glacier](/source/Taylor_Glacier) in [Victoria Land](/source/Victoria_Land),<ref>{{cite journal|doi=10.1071/MU9920065|last=Robertson|first=G|year=1992|title=Population size and breeding success of Emperor Penguins ''Aptenodytes forsteri'' at Auster and Taylor Glacier colonies, Mawson Coast, Antarctica|journal=Emu|volume=92|pages=65–71|issue=2|title-link=Mawson Coast|bibcode=1992EmuAO..92...65R }}</ref> and most recently one at [Amundsen Bay](/source/Amundsen_Bay).<ref name="Wienecke"/> Since 2009, a number of colonies have been reported on [shelf ice](/source/shelf_ice) rather than [sea ice](/source/sea_ice), in some cases moving to the shelf in years when sea ice forms late.<ref>{{Cite journal| doi = 10.1371/journal.pone.0085285| title = Emperor Penguins Breeding on Iceshelves| year = 2014| last1 = Fretwell | first1 = P. T. | last2 = Trathan | first2 = P. N. | last3 = Wienecke | first3 = B. | last4 = Kooyman | first4 = G. L. | journal = PLOS ONE| volume = 9| issue = 1| article-number = e85285 | pmid=24416381 | pmc=3885707| bibcode = 2014PLoSO...985285F| doi-access = free}}</ref> As of 2022, there were 66 known breeding colonies.<ref>{{cite web |last1=Metcalfe |first1=Tom |title=Hidden, never-before-seen penguin colony spotted from space |url=https://www.livescience.com/satellites-reveal-emperor-penguin-colony-antarctica |website=livescience.com |access-date=21 January 2023 |date=20 January 2023}}</ref>

The northernmost breeding population is on [Snow Hill Island](/source/Snow_Hill_Island), near the northern tip of the Peninsula.<ref name="Wienecke"/> Individual [vagrants](/source/Vagrancy_(biology)) have been seen on [Heard Island](/source/Heard_Island_and_McDonald_Islands),<ref>{{cite journal|vauthors=Downes MC, Ealey EH, Gwynn AM, Young PS |year=1959|title=The Birds of Heard Island|journal=Australian National Antarctic Research Report|volume=Series B1|pages=1–35}}</ref> [South Georgia](/source/South_Georgia_and_the_South_Sandwich_Islands),<ref>{{cite journal|last=Clark|first=G S|title=Eighth record of the Emperor penguin Aptenodytes forsteri at South Georgia|journal=Cormorant|year=1986|volume=13|issue=2|pages=180–181|url=http://www.marineornithology.org/PDF/13_2/13_162-187_ShortCommunications.pdf|access-date=16 May 2013}}</ref> and occasionally in New Zealand<!--South Island? Bit vague-->.<ref name=Hanzab>{{cite book|title=Handbook of Australian, New Zealand and Antarctic Birds, Vol. 1A|last=Marchant|first=S|author2=Higgins PJ|year=1990|publisher=[Oxford University Press](/source/Oxford_University_Press)|location=Melbourne}}</ref><ref>{{cite journal|vauthors=Croxall JP, Prince PA |year=1983|title=Antarctic Penguins and Albatrosses|journal=Oceanus|volume=26|pages=18–27}}</ref> The furthest north a vagrant has been recorded was in [Denmark, Western Australia](/source/Denmark%2C_Western_Australia), in November 2024.<ref>{{cite web |last1=Goerling |first1=Samantha |last2=Thannoo |first2=Jamie |last3=Barr |first3=Peter |title=Emperor penguin waddles up to surfer at WA beach in most northern recorded sighting of species |url=https://www.abc.net.au/news/2024-11-05/emperor-penguin-rare-sighting-ocean-beach-wa-denmark/104559588 |website=[ABC News](/source/ABC_News_(Australia)) |date=5 November 2024 |access-date=5 November 2024}}</ref> This individual, which is believed to have originated from eastern Antarctica, was encountered by a group of surfers shortly after it arrived in Denmark, and was taken in by conservationists at the [Department of Biodiversity, Conservation and Attractions](/source/Department_of_Biodiversity%2C_Conservation_and_Attractions) to have its condition evaluated.<ref>{{Cite web |last=Granville |first=Alan |title=Record-breaking emperor penguin swims thousands of kilometres for a beach holiday in Australia |url=https://www.stuff.co.nz/travel/360476401/record-breaking-emperor-penguin-swims-thousands-kilometres-beach-holiday-australia |access-date=6 November 2024 |website=www.stuff.co.nz}}</ref>

In 2009, the total population of emperor penguins was estimated to be at around 595,000 adult birds, in 46 known colonies spread around the Antarctic and sub-Antarctic; around 35% of the known population lives north of the [Antarctic Circle](/source/Antarctic_Circle). Major breeding colonies were located at [Cape Washington](/source/Cape_Washington), [Coulman Island](/source/Coulman_Island) in [Victoria Land](/source/Victoria_Land), [Halley Bay](/source/Halley_Bay), [Cape Colbeck](/source/Cape_Colbeck), and [Dibble Glacier](/source/Dibble_Glacier).<ref name="Fretwell">{{cite journal|author1=Fretwell PT |author2=LaRue MA |author3=Morin P |author4=Kooyman GL |author5=B Wienecke |author6=N Ratcliffe |author7=AJ Fox |author8=AH Fleming |author9=C Porter |author10=PN Trathan | year=2012| title= An Emperor Penguin Population Estimate: The First Global, Synoptic Survey of a Species from Space|journal=PLOS ONE |volume=7|issue=4|article-number=e33751| doi=10.1371/journal.pone.0033751|bibcode=2012PLoSO...733751F | pmid=22514609 | pmc=3325796|doi-access=free }}</ref> Colonies are known to fluctuate over time, often breaking into "suburbs" which move apart from the parent group, and some have been known to disappear entirely.<ref name="Wienecke"/> The [Cape Crozier](/source/Cape_Crozier) colony on the [Ross Sea](/source/Ross_Sea) shrank drastically between the first visits by the [''Discovery'' Expedition](/source/Discovery_Expedition) in 1902–03<ref name=Attenborough>{{cite AV media | author=David Attenborough | title=Attenborough's Natural Curiosities 2 | volume=Life on Ice | year=2014 | publisher=UKTV}}</ref> and the later visits by the [''Terra Nova'' Expedition](/source/Terra_Nova_Expedition) in 1910–11; it was reduced to a few hundred birds, and may have come close to extinction due to changes in the position of the ice shelf.<ref name="Stonehouse">{{Cite journal | last1 = Stonehouse | first1 = B. | title = Emperor Penguins at Cape Crozier | doi = 10.1038/203849a0 | journal = Nature | volume = 203 | issue = 4947 | pages = 849–851 | year = 1964 | bibcode = 1964Natur.203..849S | s2cid = 4188703 }}</ref> By the 1960s it had rebounded dramatically,<ref name="Stonehouse"/> but by 2009 was again reduced to a small population of around 300.<ref name="Fretwell"/>

===Conservation status===
In April 2026, the [International Union for Conservation of Nature](/source/International_Union_for_Conservation_of_Nature) (IUCN) declared the emperor penguin and [Antarctic fur seal](/source/Antarctic_fur_seal) as [endangered](/source/Endangered_species) species. The main driver of the decline of emperor penguins is the break-up and loss of sea ice as a result of rapid [climate change](/source/climate_change) caused by [greenhouse gas emissions](/source/greenhouse_gas_emissions). Satellite images taken between 2009 and 2018 have indicated a loss of approximately 10% of the overall emperor penguin population, equating to over 20,000 adult individuals. Based on this data, it has been estimated with a 45% probability that the population will decline by greater than 50% by 2073.<ref name="IUCN2026">{{Cite journal |title=''Aptenodytes forsteri'' |journal=The IUCN Red List of Threatened Species |issue=2026 |volume=2 |id=e.T22697752A197622453 |url=https://nc.iucnredlist.org/redlist/content/attachment_files/Aptenodytes_forsteri_Pre-Publication_Assessment_RLTS_T22697752A197622453_eng.pdf |accessdate=10 April 2026  |archiveurl=https://web.archive.org/web/20260411145901/https://nc.iucnredlist.org/redlist/content/attachment_files/Aptenodytes_forsteri_Pre-Publication_Assessment_RLTS_T22697752A197622453_eng.pdf |archivedate=11 April 2026 |url-status=live }}</ref><ref name="IUCN Press">{{Cite press release |date=9 April 2026 |title=Emperor penguin and Antarctic fur seal now Endangered due to climate change – IUCN Red List |url=https://iucn.org/press-release/202604/emperor-penguin-and-antarctic-fur-seal-now-endangered-due-climate-change-iucn |access-date=10 April 2026 |location=Gland, Switzerland |publisher=International Union for Conservation of Nature }}</ref>

{{blockquote
|text=After careful consideration of different possible threats, we concluded that human-induced climate change poses the most significant threat to emperor penguins. Early sea-ice break-up in spring is already affecting colonies around the Antarctic, and further changes in sea-ice will continue to affect their breeding, feeding and moulting habitat.
|author=Dr Philip Trathan, member of the IUCN SSC Penguin Specialist Group<ref name="IUCN Press"/>}}

The species was previously listed as [near threatened](/source/Near-threatened_species) by the IUCN, having been listed as [least concern](/source/Least-concern_species) prior to 2012.<ref name="iucn status 19 November 2021">{{cite iucn |author=BirdLife International |date=2020 |title=''Aptenodytes forsteri'' |volume=2020 |article-number=e.T22697752A157658053 |doi=10.2305/IUCN.UK.2020-3.RLTS.T22697752A157658053.en |access-date=19 November 2021}}</ref><ref>{{cite web|title=Recently recategorised species |url=http://www.birdlife.org/action/science/species/global_species_programme/whats_new.html |publisher=Birdlife International (2012) |access-date=14 June 2012 |archive-url=https://web.archive.org/web/20070828022837/http://www.birdlife.org/action/science/species/global_species_programme/whats_new.html |archive-date=28 August 2007}}</ref> Along with nine other species of penguin, it is currently under consideration for inclusion under the US [Endangered Species Act](/source/Endangered_Species_Act). The primary causes for an increased risk of species endangerment are declining food availability, due to the [effects of climate change](/source/effects_of_global_warming) and industrial fisheries on the crustacean and fish populations. Other reasons for the species's placement on the Endangered Species Act's list include disease, [habitat destruction](/source/habitat_destruction), and disturbance at breeding colonies by humans. Of particular concern is the impact of tourism.<ref>{{cite journal |author1=Burger J. |author2=Gochfeld M. | year = 2007 | title = Responses of Emperor Penguins (''Aptenodytes forsteri'') to encounters with ecotourists while commuting to and from their breeding colony |journal = Polar Biology | volume = 30 | issue = 10| pages = 1303–1313 | doi = 10.1007/s00300-007-0291-1 |bibcode=2007PoBio..30.1303B |s2cid=9358798 }}</ref> One study concluded that emperor penguin chicks in a crèche become more apprehensive following a helicopter approach to {{cvt|1000|m}}.<ref>{{cite journal|vauthors=Giese M, Riddle M |year=1997|title=Disturbance of emperor penguin ''Aptenodytes forsteri'' chicks by helicopters|journal=Polar Biology|volume=22|issue=6|pages=366–71|doi=10.1007/s003000050430|s2cid=2548268}}</ref>

right|thumb|Halley Bay Colony in 1999
Population declines of 50% in the [Terre Adélie](/source/Ad%C3%A9lie_Land) region were observed due to an increased death rate among adult birds, especially males, during an abnormally prolonged warm period in the late 1970s, which resulted in reduced sea-ice coverage. On the other hand, egg hatching success rates declined when the sea-ice extent increased; chick deaths also increased; the species is therefore considered to be highly sensitive to climatic changes.<ref>{{cite journal|title=Emperor penguins and climate change|last=Barbraud|first=C.|author2=Weimerskirch H.|journal=Nature|year=2001|volume=411|issue=6834|pages=183–186|pmid=11346792|doi=10.1038/35075554|bibcode=2001Natur.411..183B|s2cid=205016817}}</ref> In 2009, the Dion Islands colony, which had been extensively studied since 1948, was reported to have completely disappeared at some point over the previous decade, the fate of the birds unknown. This was the first confirmed loss of an entire colony.<ref>{{Cite journal | last1 = Trathan | first1 = P. N. | last2 = Fretwell | first2 = P. T. | last3 = Stonehouse | first3 = B. | editor1-last = Briffa | editor1-first = Mark | title = First Recorded Loss of an Emperor Penguin Colony in the Recent Period of Antarctic Regional Warming: Implications for Other Colonies | doi = 10.1371/journal.pone.0014738 | journal = PLOS ONE | volume = 6 | issue = 2 | article-number = e14738 | year = 2011 | pmid =  21386883| pmc =3046112 | bibcode = 2011PLoSO...614738T | doi-access = free }}</ref> Beginning in September 2015, a strong [El Niño](/source/El_Ni%C3%B1o), strong winds, and record low amounts of sea ice resulted in "almost total breeding failure" with the deaths of thousands of emperor chicks for three consecutive years within the [Halley Bay](/source/Halley_Bay) colony, the second largest emperor penguin colony in the world. Concomitantly,  there was immigration of breeding penguins to the Dawson-Lambton colony {{cvt|55|km}} south, in which a tenfold population increase was observed between 2016 and 2018. However, this increase was much smaller than the total number of breeding adults lost from the Halley Bay colony.<ref>{{cite journal |last1=Fretwell |first1=Peter T. |last2=Trathan |first2=Philip N. |title=Emperors on thin ice: Three years of breeding failure at Halley Bay |journal=Antarctic Science |volume=31 |issue=3 |date=25 April 2019 |pages=133–138 |doi=10.1017/S0954102019000099 |bibcode=2019AntSc..31..133F |doi-access=free }}</ref>

In January 2009, a study from the [Woods Hole Oceanographic Institution](/source/Woods_Hole_Oceanographic_Institution) concluded that [global climate change](/source/global_climate_change) could push the emperor penguin to the brink of extinction by the year 2100. The study constructed a mathematical model to predict how the loss of sea ice from climate warming would affect a big colony of emperor penguins at [Terre Adélie](/source/Terre_Ad%C3%A9lie), Antarctica. The study forecasted an 87% decline in the colony's population, from three thousand breeding pairs in 2009 to four hundred breeding pairs in 2100.<ref>{{Cite journal | last1 = Jenouvrier | first1 = S. | last2 = Caswell | first2 = H. | last3 = Barbraud | first3 = C. | last4 = Holland | first4 = M. | last5 = Str Ve | first5 = J. | last6 = Weimerskirch | first6 = H. | doi = 10.1073/pnas.0806638106 | title = Demographic models and IPCC climate projections predict the decline of an emperor penguin population | journal = Proceedings of the National Academy of Sciences | volume = 106 | issue = 6 | pages = 1844–1847 | year = 2009 | pmid =  19171908| pmc = 2644125| bibcode = 2009PNAS..106.1844J | doi-access = free }}</ref>

Another study by the Woods Hole Oceanographic Institution in 2014 again concluded that emperor penguins are at risk from global warming, which is melting the sea ice. This study predicted that by 2100 all colonies of emperor penguins will be declining in numbers, mostly due to loss of habitat. Loss of ice reduces the supply of [krill](/source/krill), which is a primary food for emperor penguins.<ref>{{cite web| url=https://www.theguardian.com/environment/2014/jun/29/emperor-penguins-at-risk-of-extinction-scientists-warn | title=Emperor penguins at risk of extinction, scientists warn|work=The Guardian | author=Goldenberg, Suzanne |date=30 June 2014 | publisher=Guardian News and Media Limited | access-date=28 January 2015}}</ref> A 2023 study found that climate change could cause more than 90% of emperor penguin colonies to face [quasi-extinction](/source/quasi-extinction) from breeding failures, as rising temperatures lead to the loss of the sea ice.<ref>{{cite journal |last1=Fretwell |first1=Peter |last2=Boutet |first2=Aude |last3=Ratcliffe |first3=Norman |title=Record low 2022 Antarctic sea ice led to catastrophic breeding failure of emperor penguins |journal=Communications Earth & Environment |date=2023 |volume=4 |issue=1 |page=273 |doi=10.1038/s43247-023-00927-x |bibcode=2023ComEE...4..273F |s2cid=261198955 |doi-access=free }}</ref>

==Behaviour==
[[File:2007 Snow-Hill-Island Luyten-De-Hauwere-Emperor-Penguin-03.jpg|thumb|right|An emperor penguin [colony](/source/seabird_colony) on [Snow Hill Island](/source/Snow_Hill_Island)]]

[[File:Activity-Time-Budget-during-Foraging-Trips-of-Emperor-Penguins-pone.0050357.s001.ogv|thumb|right|A group of emperor penguins synchronously diving from the edge of some ice in Antarctica; video from Watanabe et al., [https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0050357 "Activity Time Budget during Foraging Trips of Emperor Penguins"]]]

The emperor penguin is a [social animal](/source/social_animal) in its nesting and its foraging behaviour; birds hunting together may coordinate their diving and surfacing.<ref name=Kooy71>{{cite journal|vauthors=Kooyman GL, Drabek CM, Elsner R, Campbell WB |year=1971|title=Diving behaviour of the Emperor Penguin ''Aptenodytes forsteri''|journal=Auk|volume=88|pages=775–95 |url=http://sora.unm.edu/sites/default/files/journals/auk/v088n04/p0775-p0795.pdf|doi=10.2307/4083837|issue=4|jstor=4083837}}</ref> Individuals may be active day or night. A mature adult travels throughout most of the year between the breeding colony and ocean foraging areas; the species disperses into the oceans from January to March.<ref name=Hanzab/>

The American [physiologist](/source/physiology) Gerry Kooyman revolutionized the study of penguin foraging behaviour in 1971 when he published his results from attaching automatic dive-recording devices to emperor penguins. He found that the species reaches depths of {{cvt|265|m}}, with dive periods of up to 18 minutes.<ref name=Kooy71 /> Later research revealed a small female had dived to a depth of {{cvt|535|m}} near [McMurdo Sound](/source/McMurdo_Sound). It is possible that emperor penguins can dive for even deeper and longer periods, as the accuracy of the recording devices is diminished at greater depths.<ref>{{Harvnb|Williams|1995|p=89}}.</ref> Further study of one bird's diving behaviour revealed regular dives to {{cvt|150|m}} in water around {{cvt|900|m}} deep, and shallow dives of less than {{cvt|50|m}}, interspersed with deep dives of more than {{cvt|400|m}} in depths of {{cvt|450|to|500|m}}.<ref name=Ancel92>{{cite journal|vauthors=Ancel A, Kooyman GL, Ponganis PJ, Gendner JP, Lignon J, Mestre X |year=1992|title=Foraging behaviour of Emperor Penguins as a resource detector in Winter and Summer|journal=Nature|volume=360|pages=336–39|doi=10.1038/360336a0|issue=6402|bibcode=1992Natur.360..336A|s2cid=4274467}}</ref> This was suggestive of feeding near or at the sea bottom.<ref name=Will156>{{Harvnb|Williams|1995|p=156}}.</ref> In 1994, a penguin from [Auster rookery](/source/Auster_rookery) reached a depth of {{cvt|564|m}}; the entire dive took him 21.8 min.<ref name=Wienecke_2007>{{cite journal|title=Extreme dives by free-ranging emperor penguins |author1=Wienecke, B.|author2=Robertson, G.|author3=Kirkwood, R.|author4=Lawton, K. |date=2007 |journal=Polar Biology |volume=30 |issue=2 |pages=133–142 |doi=10.1007/s00300-006-0168-8|s2cid=455088}}</ref>

Both male and female emperor penguins forage for food up to {{cvt|500|km}} from colonies while collecting food to feed chicks, covering {{cvt|82|-|1454|km}} per individual per trip. A male returning to the sea after incubation heads directly out to areas of permanent open water, known as [polynya](/source/polynya)s, around {{cvt|100|km}} from the colony.<ref name=Ancel92 />

An efficient swimmer, the emperor penguin exerts pressure with both its upward and downward strokes while swimming.<ref name=NatGeoHile>{{cite web|url=http://news.nationalgeographic.com/news/2004/03/0329_040329_TVpenguins.html|archive-url=https://web.archive.org/web/20040603052124/http://news.nationalgeographic.com/news/2004/03/0329_040329_TVpenguins.html|archive-date=3 June 2004|title=Emperor Penguins: Uniquely Armed for Antarctica|access-date=31 March 2008|author=Hile J|date=29 March 2004|work=National Geographic website|publisher=National Geographic}}</ref> The upward stroke works against buoyancy and helps maintain depth.<ref>{{cite journal|last=Lovvorn|first=J. R.|year=2001|title=Upstroke thrust, drag effects, and stroke-glide cycles in wing-propelled swimming by birds|journal=American Zoologist|volume=41|pages=154–165|doi=10.1093/icb/41.2.154|issue=2|doi-access=free}}</ref> Its average swimming speed is {{cvt|6|–|9|km/h}}.<ref>{{cite journal|vauthors=Kooyman GL, Ponganis PJ, Castellini MA, Ponganis EP, Ponganis KV, Thorson PH, Eckert SA, LeMaho Y |year=1992|title=Heart rates and swim speeds of emperor penguins diving under sea ice|journal=Journal of Experimental Biology|volume=165|issue=1|pages=1161–80|doi=10.1242/jeb.165.1.161|pmid=1588249|url=http://jeb.biologists.org/cgi/reprint/165/1/161.pdf|doi-access=free|bibcode=1992JExpB.165..161K }}</ref> On land, the emperor penguin alternates between walking with a wobbling gait and tobogganing—sliding over the ice on its belly, propelled by its feet and wing-like flippers. Like all penguins, it is flightless.{{sfn|Williams|1995|p=3}} The emperor penguin is a very powerful bird. In one case, a crew of six men, trying to capture a single male penguin for a zoo collection, were repeatedly tossed around and knocked over before all of the men had to collectively tackle the bird, which weighs about half as much as a man.<ref name = "Wood">{{cite book | author = Wood, Gerald | title = The Guinness Book of Animal Facts and Feats | year = 1983 | publisher = Guinness Superlatives | isbn = 978-0-85112-235-9 | url-access = registration | url = https://archive.org/details/guinnessbookofan00wood }}</ref>

As a defence against the cold, a colony of emperor penguins forms a compact huddle (also known as the turtle formation) ranging in size from ten to several hundred birds, with each bird leaning forward on a neighbour. As the [wind chill](/source/wind_chill) is the least severe in the center of the colony, all the juveniles are usually huddled there. Those on the outside upwind tend to shuffle slowly around the edge of the formation and add themselves to its leeward edge, producing a slow churning action, and giving each bird a turn on the inside and on the outside.<ref>{{cite journal |author1=Pinshow B. |author2=Fedak M.A. |author3=Battles D.R |author4=Schmidt-Nielsen K. |s2cid=19141176 | year = 1976 | title = Energy expenditure for thermoregulation and locomotion in emperor penguins | journal = American Journal of Physiology | volume = 231 | issue = 3| pages = 903–12 | pmid = 970474 |doi=10.1152/ajplegacy.1976.231.3.903 }}</ref><ref name=twsD36>{{cite news
 |author= Rebecca Morelle
 |author-link=Rebecca Morelle
 |title= Penguin huddle secrets revealed with time lapse footage
 |newspaper= BBC News
 |quote= The mystery of how penguins stay warm while they huddle has been revealed by an international team of scientists.&nbsp;... Dr Zitterbart explained: "The colony would stay still for most of the time, but every 30–60 seconds one penguin or a group of penguin starts to move – just a little bit. "This makes the surrounding ones move – and all of a sudden this moves throughout the colony like a wave."
 |date= 2 June 2011
 |url= https://www.bbc.co.uk/news/science-environment-13616778
 |access-date= 4 June 2011
}}</ref>

===Predators===
[[File:Fish8426 - Flickr - NOAA Photo Library.jpg|thumb|Emperor penguin attacked by a [leopard seal](/source/leopard_seal)]]
thumb|Giant petrel and emperor penguin chicks

The emperor penguin's predators include birds and aquatic mammals. [Southern giant petrel](/source/Southern_giant_petrel)s (''Macronectes giganteus'') are the predominant land predator of chicks, responsible for over one-third of chick deaths in some colonies; they also scavenge dead penguins.  The [south polar skua](/source/south_polar_skua) (''Stercorarius maccormicki'') mainly scavenges for dead chicks, as the live chicks are usually too large to be attacked by the time of its annual arrival in the colony.<ref>{{Harvnb|Williams|1995|p=40}}.</ref> Occasionally, a parent may attempt to defend its chick from attack, although it may be more passive if the chick is weak or sickly.<ref name="Prevost">{{cite book|title=Ecologie du manchot empereur|last=Prévost|first=J|year=1961|publisher=Hermann|location=Paris}}</ref>

The only known predators known to attack healthy adults, and which attack emperor penguins in the ocean, are the [leopard seal](/source/leopard_seal) (''Hydrurga leptonyx''), which takes adult birds and fledglings soon after they enter the water.<ref name=Kooy90Colony>{{cite journal|vauthors=Kooyman GL, Croll DA, Stone S, Smith S |year=1990|title=Emperor penguin colony at Cape Washington, Antarctica|journal=[Polar Record](/source/Polar_Record)|volume=26|issue=157|pages=103–08|doi=10.1017/S0032247400011141|bibcode=1990PoRec..26..103K |s2cid=129187086 }}</ref> [Orca](/source/Orca)s (''Orcinus orca'') mostly take adult birds at sea, although they will attack penguins of any age in or near water.<ref name="Prevost"/>

===Courtship and breeding===
Although emperor penguins can breed at around three years of age, they generally do not begin breeding for another one to three years.<ref name=Will159>{{Harvnb|Williams|1995|p=159}}.</ref> The yearly reproductive cycle begins at the start of the Antarctic winter, in March and April, when all mature emperor penguins travel to colonial nesting areas, often walking {{cvt|50|to|120|km}} inland from the edge of the pack ice.<ref name=Will158>{{Harvnb|Williams|1995|p=158}}.</ref> The start of travel appears to be triggered by decreasing day lengths; emperor penguins in captivity have been induced successfully into breeding by using artificial lighting systems mimicking seasonal Antarctic day lengths.<ref>{{cite journal|title=The endocrine control of reproduction and molt in male and female Emperor (''Aptenodytes forsteri'') and Adélie (''Pygoscelis adeliae'') Penguins. I. Annual changes in plasma levels of gonadal steroids and luteinizing hormone|journal=Gen. Comp. Endocrinol.|volume=62|pages=43–53|doi=10.1016/0016-6480(86)90092-4|year=1986|author=Groscolas, R|pmid=3781216|last2=Jallageas|first2=M|last3=Goldsmith|first3=A|last4=Assenmacher|first4=I|issue=1}}</ref> The [British Antarctic Survey](/source/British_Antarctic_Survey) used [satellite imagery](/source/satellite_imagery) to find new emperor penguin breeding sites in Antarctica, a discovery that increased the estimated population of the emperor penguins by 5 to 10 per cent to around 278,000 breeding pairs. Given their remote locations and harsh weather conditions, penguin populations are found by scanning aerial imagery and locating enormous pages of ice that have been stained with their [guano](/source/guano). The new discoveries increased the number of known breeding sites from 50 to 61.<ref>{{cite news |last=Amos |first=Jonathon |url=https://www.bbc.com/news/science-environment-53549299 |title=Climate change: Satellites find new colonies of Emperor penguins |work=[BBC News](/source/BBC_News) |date=5 August 2020 |access-date=25 August 2020 }}</ref>

[[Image:PENGUIN LIFECYCLE H.JPG|left|thumb|The [life-cycle](/source/Biological_life_cycle) of the emperor penguin]]
The penguins start [courtship](/source/courtship_display) in March or April, when the temperature can be as low as {{cvt|-40|°C}}. A lone male gives an ecstatic display, in which it stands still and places its head on its chest before inhaling and giving a courtship call for 1–2 seconds; it then moves around the colony and repeats the call. A male and female then stand face to face, with one extending its head and neck up and the other mirroring it; they both hold this posture for several minutes. Once in pairs, couples waddle around the colony together, with the female usually following the male. Before [copulation](/source/copulation_(zoology)), one bird bows deeply to its mate, its bill pointed close to the ground, and its mate then does the same.<ref name=Will157>{{Harvnb|Williams|1995|p=157}}.</ref>

Contrary to popular belief, emperor penguins do not mate for life; they are [serially monogamous](/source/serial_monogamy), having only one mate each year, and remaining faithful to that mate. However, fidelity between years is only around 15%.<ref name=Will157/> The narrow window of opportunity available for mating appears to be an influence, as there is a priority to mate and breed which usually precludes waiting for the previous year's partner to arrive at the colony.<ref name=Will55>{{Harvnb|Williams|1995|p=55}}.</ref>

[[Image:Aptenodytes forsteri MHNT.jpg|thumb|upright|right|The [egg](/source/egg_(biology)) of the emperor penguin. It is {{nowrap|13.5 × 9.5}} cm and avocado-shaped.]]
The female penguin lays one {{cvt|460|-|470|g}} [egg](/source/bird_egg) in May or early June;<ref name = Will157/> it is vaguely pear-shaped, pale greenish-white, and measures around {{cvt|12|×|8|cm}}.<ref name=Will158/> It represents just 2.3% of its mother's body weight, making it one of the smallest eggs relative to the maternal weight in any bird species.<ref name=Will23>{{Harvnb|Williams|1995|p=23}}.</ref> 15.7% of the weight of an emperor penguin egg is shell; like those of other penguin species, the shell is relatively thick, which helps minimize risk of breakage.<ref name=Will24>{{Harvnb|Williams|1995|p=24}}</ref>

After laying, the mother's food reserves are exhausted. She carefully transfers the egg to the male and then returns to the sea for two months to feed.<ref name=Will158/> The transfer of the egg can be awkward and difficult, especially for first-time parents, and many couples drop or crack the egg in the process. When this happens, the chick inside is quickly lost, as the egg cannot withstand the sub-freezing temperatures on the icy ground for more than one to two minutes. When a couple loses an egg in this manner, their relationship is ended and both walk back to the sea, returning to the colony again the next year to make new attempts at mating. After a successful transfer of the egg to the male penguin, the female departs for the sea and the male spends the dark, stormy winter [incubating](/source/avian_incubation) the egg against his [brood patch](/source/brood_patch), a patch of skin without feathers. There he balances it on the tops of his feet, engulfing it with loose skin and feathers for around 65–75 days until hatching.<ref name=Will157/> The emperor is the only penguin species where the male alone incubates; in all other penguin species both parents take shifts incubating.<ref>{{Harvnb|Williams|1995|p=27}}.</ref> By the time the egg hatches, the male will have fasted for around 120 days since arriving at the colony.<ref name=Will157/> To survive the cold and savage winds of up to {{cvt|200|km/h}}, 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. In the four months of travel, courtship, and incubation, the male may lose as much as {{cvt|20|kg}}, dropping from a total mass of {{cvt|38|to|18|kg}}.<ref>{{cite journal|first=J. P.|last=Robin|author2=M. Frain|author3=C. Sardet |author4=R. Groscolas |author5=Y. Le Maho |year=1988|title= Protein and lipid utilization during long-term fasting in emperor penguins|pmid=3337270|journal=Am. J. Physiol. Regul. Integr. Comp. Physiol.|volume=254|pages=R61–R68|issue=1 Pt 2|doi=10.1152/ajpregu.1988.254.1.R61}}</ref><ref>{{cite journal|first=Y.|last=Le Maho|author2=P. Delclitte |author3=J Chatonnet |title=Thermoregulation in fasting emperor penguins under natural conditions|journal=Am. J. Physiol.|volume=231|pages=913–922|year=1976|pmid=970475|issue=3|doi=10.1152/ajplegacy.1976.231.3.913|doi-access=free}}</ref>

Hatching may take as long as two or three days to complete, as the shell of the egg is thick. Newly hatched chicks are [semi-altricial](/source/Altriciality), covered with only a thin layer of down and entirely dependent on their parents for food and warmth.<ref name=Will28/> The chick usually hatches before the mother's return, and the father feeds it a [curd](/source/curd)-like substance composed of 59% [protein](/source/protein) and 28% [lipid](/source/lipid), which is secreted by a gland in his [oesophagus](/source/oesophagus).<ref>{{cite journal|vauthors=Prévost J, Vilter V |year=1963|title=Histologie de la sécrétion oesophagienne du Manchot empereur|journal=Proceedings of the XIII International Ornithological Conference|pages=1085–94|language=fr}}</ref> This ability to produce "[crop milk](/source/crop_milk)" in birds is only found in pigeons, flamingos and male emperor penguins. After the chick hatches, the father is able to secrete this crop milk for only 3 to 7 days; this will temporarily sustain the chick until the mother returns to the colony with food from fishing at sea to properly feed the chick. If the mother penguin's arrival is delayed, the chick will die. Research indicates that 10–20% of female emperor penguins do not return to their colony from foraging at sea, most victims of the harsh winter weather conditions or predators.<ref>{{Cite web |url=http://www.sciencealert.com/mothers-milk-best-for-growing-babies-and-that-includes-baby-pigeons |title=ScienceAlert 19 SEP 2011 |access-date=22 December 2016 |archive-date=30 March 2019 |archive-url=https://web.archive.org/web/20190330170236/https://www.sciencealert.com/mothers-milk-best-for-growing-babies-and-that-includes-baby-pigeons |url-status=dead }}</ref> The young chick is [brooded](/source/offspring) in what is called the "guard phase", spending time balanced on its parent's feet and kept warm by the brood patch.<ref name = Will28/>

left|thumb|Emperor penguin feeding a chick
The female penguin returns at any time from hatching up to ten days afterwards, from mid-July to early August.<ref name=Will158/> 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 partially digested fish, squid and krill that she has stored in her stomach. The male is often reluctant to surrender the chick he has been caring for all winter to its mother, but he soon leaves to take his turn at sea, spending 3 to 4 weeks feeding there before returning.<ref name=Will158/> The parents then take turns, one [brooding](/source/offspring) while the other forages at sea.<ref name=Will157 /> If either parent is delayed or fails to return to the colony, the lone parent will return to the sea to feed, leaving the chick to die.<ref>{{cite journal|title=Behavioral changes in fasting emperor penguins: evidence for a "refeeding signal" linked to a metabolic shift|author=Robin, Jean-Patrice|author2=Boucontet, Laurent|author3=Chillet, Pascal|author4=Groscolas, René|journal=Am. J. Physiol.|volume=274|issue=Regulatory Integrative Comp. Physiol. 43|pages=R746–R753|year=1998|doi=10.1152/ajpregu.1998.274.3.R746|pmid=9530242}}</ref> Abandoned eggs do not hatch and orphaned chicks never survive.

Female emperors who failed to find a mate to breed with or have lost their own chick may attempt to adopt a stray chick or steal the chick of another female. The mother of the chick and neighbouring females will fight to protect the chick, or to reclaim it if it has been successfully stolen. These scuffles involving several birds often result in the chick being smothered or trampled to death.  Chicks which have been adopted or stolen are quickly abandoned once again, as it is impossible for the female to feed and care for the chick alone. The orphaned chicks wander around the colony attempting to seek food and protection from other adults. They will even try to shelter themselves in an adult bird's brood patch already occupied by its own chick. These stray chicks are brusquely driven away by the adults and their chicks. All orphaned chicks will rapidly become weaker and die of starvation, or freeze to death.<ref>{{cite video |url=https://www.bbc.co.uk/nature/life/Emperor_Penguin |title=Life in the Freezer |publisher=BBC |last=Attenborough |first=David (narrator) |access-date=3 February 2015 |archive-url=https://web.archive.org/web/20180824013121/http://www.bbc.co.uk/nature/life/Emperor_Penguin |archive-date=24 August 2018 |chapter=Cold comfort }}</ref><ref>{{cite journal |author=Robin, Jean-Patrice |author2=Boucontet, Laurent |author3=Chillet, Pascal |author4=Groscolas, René |year=1998 |title=Behavioral changes in fasting emperor penguins: evidence for a 'refeeding signal' linked to a metabolic shift |url=https://journals.physiology.org/doi/pdf/10.1152/ajpregu.1998.274.3.R746 |journal=Am. J. Physiol. |volume=274 |issue=Regulatory Integrative Comp. Physiol. 43 |pages=R746–R753 |doi=10.1152/ajpregu.1998.274.3.R746 |pmid=9530242|url-access=subscription }}</ref>

About 45–50 days after hatching, the chicks form a [crèche](/source/cr%C3%A8che_(zoology)), huddling together for warmth and protection. During this time, both parents forage at sea and return periodically to feed their chicks.<ref name="Will28">{{Harvnb|Williams|1995|p=28}}.</ref> A crèche may consist of from around a dozen to up to several thousand chicks densely packed together and is essential for surviving the low Antarctic temperatures.<ref name="Will30">{{Harvnb|Williams|1995|p=30}}.</ref>
thumb|Juvenile plumage
From early November, chicks begin moulting into juvenile plumage, which takes up to two months and is usually not completed by the time they leave the colony. Adults cease feeding them during this time. All birds make the considerably shorter trek to the sea in December and January. The birds spend the rest of the summer feeding there.<ref name=Kooy90Colony/><ref>{{Cite journal |last1=Pütz |first1=K. |last2=Plötz |first2=J. |year=1991 |title=Moulting starvation in emperor penguin (''Aptenodytes forsteri'') chicks |journal=Polar Biology |volume=11 |issue=4 |pages=253–258 |doi=10.1007/BF00238459 |bibcode=1991PoBio..11..253P |s2cid=28535093 }}</ref>

===Feeding===
The emperor penguin's diet consists mainly of fish, [crustacean](/source/crustacean)s and [cephalopod](/source/cephalopod)s,<ref>{{cite journal |vauthors=Cherel Y, Kooyman GL | year = 1998 | title = Food of emperor penguins (''Aptenodytes forsteri'') in the western Ross Sea, Antarctica | journal = Marine Biology | volume = 130 | issue = 3| pages = 335–44 | doi = 10.1007/s002270050253 | bibcode = 1998MarBi.130..335C | s2cid = 62841771 }}</ref> although its composition varies from population to population. Fish are usually the most important food source, and the [Antarctic silverfish](/source/Antarctic_silverfish) (''Pleuragramma antarcticum'') makes up the bulk of the bird's diet. Other prey commonly recorded include other fish of the family [Nototheniidae](/source/Nototheniidae), the [glacial squid](/source/glacial_squid) (''Psychroteuthis glacialis''), and the [hooked squid](/source/hooked_squid) species ''[Kondakovia longimana](/source/Kondakovia_longimana)'', as well as [Antarctic krill](/source/Antarctic_krill) (''Euphausia superba'').<ref name=Will156/> The emperor penguin searches for prey in the open water of the [Southern Ocean](/source/Southern_Ocean), in either ice-free areas of open water or tidal cracks in pack ice.<ref name="ADW"/> One of its feeding strategies is to dive to around {{cvt|50|m}}, where it can easily spot [sympagic](/source/sympagic) fish like the [bald notothen](/source/bald_notothen) (''Pagothenia borchgrevinki'') swimming against the bottom surface of the sea-ice; it swims up to the bottom of the ice and catches the fish. It then dives again and repeats the sequence about half a dozen times before surfacing to [breath](/source/breath)e.<ref>{{cite journal|vauthors=Ponganis PJ, Van Dam RP, Marshall G, Knower T, Levenson DH |year=2003|title=Sub-ice foraging behavior of emperor penguins|journal=Journal of Experimental Biology|volume=203 |issue=21 |pages=3275–78 |doi=10.1242/jeb.203.21.3275|pmid=11023847|url=http://jeb.biologists.org/cgi/reprint/203/21/3275.pdf}}</ref>

==Relationship with humans==

===In zoos and aquariums===
[[File:Penguins 2 bg 111602.jpg|thumb|Two [Adélie penguin](/source/Ad%C3%A9lie_penguin)s and an emperor penguin at [SeaWorld San Diego](/source/SeaWorld_San_Diego)]]

Since the 1930s, there have been several attempts at keeping emperor penguins in captivity. [Malcolm Davis](/source/Malcolm_Davis) of the [National Zoological Park](/source/National_Zoological_Park_(United_States)) made early attempts at keeping penguins, capturing several from Antarctica.<ref name=obit>{{cite journal |last1=Behle |first1=William H. |last2=Storer |first2=Robert W. |last3=Whitney |first3=Nathaniel R. |last4=Manville |first4=Richard H. |last5=Orr |first5=Robert T. |last6=Hertlein |first6=Leo G. |title=Obituaries |journal=The Auk |date=October 1971 |volume=88 |issue=4 |page=962 |doi=10.2307/4083872 |jstor=4083872 }}</ref> He successfully transferred penguins to the National Zoological Park on 5 March 1940,<ref>{{cite web |title=Record Unit 74 Records, 1887-1966 |url=https://siarchives.si.edu/collections/siris_arc_216681 |website=Smithsonian Institution Archives |access-date=14 December 2020}}</ref> where they lived for up to 6 years.<ref name=obit/>

Until the 1960s, keeping attempts were largely unsuccessful, as knowledge of penguin keeping in general was limited and acquired by trial and error. The first to achieve a level of success was [Aalborg Zoo](/source/Aalborg_Zoo) where a chilled house was built especially for this Antarctic species. One individual lived for 20 years at the zoo and a chick was hatched there, but died shortly after.<ref>{{cite web|url=http://aalborgzoo.dk/UserFiles/file/75-aar.pdf|title=75 år med dyrebare oplevelser|publisher=Aalborg Zoo|access-date=13 February 2018|year=2010|archive-date=13 February 2018|archive-url=https://web.archive.org/web/20180213195949/http://aalborgzoo.dk/UserFiles/file/75-aar.pdf}}</ref>

Today the species, considered a [flagship species](/source/flagship_species), is kept at just a few zoos and public aquariums in North America and Asia. Emperor penguins were first successfully bred at [SeaWorld San Diego](/source/SeaWorld_San_Diego); more than 20 birds have hatched there since 1980.<ref>{{cite journal|last=Todd|first=FS|year=1986|title=Techniques for propagating King and Emperor penguins ''Aptenodytes patagonica'' and ''A. forsteri'' at Sea World, San Diego|journal=International Zoo Yearbook|volume=26|issue=1|pages=110–124|doi=10.1111/j.1748-1090.1987.tb03144.x }}</ref><ref>{{cite web|url=http://www.seaworld.org/animal-info/animal-bytes/animalia/eumetazoa/coelomates/deuterostomes/chordata/craniata/aves/sphenisciformes/emperor-penguin.htm|title=Animal Bytes – Penguins|access-date=23 March 2008|year=2008|work=SeaWorld official website|publisher=SeaWorld|archive-url=https://web.archive.org/web/20080403013523/http://www.seaworld.org/Animal-info/animal-bytes/animalia/eumetazoa/coelomates/deuterostomes/chordata/craniata/aves/sphenisciformes/emperor-penguin.htm|archive-date=3 April 2008}}</ref> Fifty-five individuals were counted in captivity in North American zoos and aquaria in 1999.<ref>{{cite journal|vauthors=Diebold EN, Branch S, Henry L |year=1999|title=Management of penguin populations in North American zoos and aquariums|journal=Marine Ornithology|volume=27|pages=171–76|doi=10.5038/2074-1235.27.1.438 |url=http://www.marineornithology.org/PDF/27/27_21.pdf|access-date= 31 March 2008}}</ref> In China, the emperor penguin was first bred at [Nanjing Underwater World](/source/Nanjing_Underwater_World) in 2009,<ref>{{cite web | url=http://english.sina.com/technology/p/2009/0210/217587.html | title=First emperor penguin egg laid in China | work=english.sina.com | date=11 February 2009 | access-date=13 February 2018 |archive-url=https://web.archive.org/web/20210723194521/http://english.sina.com/technology/p/2009/0210/217587.html |archive-date=23 July 2021 |url-status=dead}}</ref> followed by Laohutan Ocean Park in [Dalian](/source/Dalian) in 2010.<ref>{{cite web | url=http://news.xinhuanet.com/english2010/sci/2010-08/19/c_13452843.htm | title=China hatches first emperor penguin | access-date=28 January 2015 | author=Tong, Xiong | work=english.news.cn | date=19 August 2010 | archive-url=https://web.archive.org/web/20151109054113/http://news.xinhuanet.com/english2010/sci/2010-08/19/c_13452843.htm | archive-date=9 November 2015}}</ref> Since then it has been kept and bred at a few other facilities in China, and the only confirmed twin emperor penguins (the species normally lays just one egg) hatched at Sun Asia Ocean World in Dalian in 2017.<ref>{{cite web | url=http://www.ecns.cn/m/2017/11-04/279661.shtml | title=World's first twin penguins born in China | work=ecns.cn | date=4 November 2017 | access-date=13 February 2018 }}</ref> In Japan, the species is housed at the [Port of Nagoya Public Aquarium](/source/Port_of_Nagoya_Public_Aquarium) and Wakayama [Adventure World](/source/Adventure_World_(Japan)), with successful hatching at Adventure World.<ref>{{cite web|url=http://www.japantimes.co.jp/news/2011/11/02/national/penguin-chick-makes-public-debut/ | title=Penguin chick makes public debut |work= The Japan Times | date=2 November 2011  | access-date=28 January 2015}}</ref>

===Penguin rescue, rehabilitation and release===
In June 2011, a juvenile emperor penguin was found on the beach at [Peka Peka](/source/Peka_Peka), north of [Wellington](/source/Wellington) in New Zealand. He had consumed {{cvt|3|kg}} of sand, which he had apparently mistaken for snow, as well as sticks and stones, and had to undergo a number of operations to remove these to save his life. Following recovery, on 4 September, the juvenile, named "[Happy Feet](/source/Happy_Feet_(penguin))" (after the [2006 film](/source/Happy_Feet)), was fitted with a tracking device and released into the Southern Ocean {{cvt|80|km}} north of [Campbell Island](/source/Campbell_Island%2C_New_Zealand).<ref name="TVNZ_4387573">{{cite web |url=http://tvnz.co.nz/national-news/happy-feet-s-trek-boon-scientists-4387573 |title=Happy Feet's trek a boon for scientists |date=6 September 2011 |work=[Television New Zealand](/source/Television_New_Zealand) |access-date=29 September 2011|archive-url=https://web.archive.org/web/20140902202733/http://tvnz.co.nz/national-news/happy-feet-s-trek-boon-scientists-4387573|archive-date=2 September 2014|url-status=dead}}</ref><ref>[https://web.archive.org/web/20230323154925/https://www.sfgate.com/news/article/New-Zealand-releases-emperor-penguin-Happy-Feet-2310974.php New Zealand releases penguin Happy Feet]. Associated Press, 5 September 2011</ref> However, 8 days later scientists lost contact with the bird, suggesting that the transmitter had fallen off (considered likely) or that he had been eaten by a predator (considered less likely).<ref>[https://www.bbc.co.uk/news/world-asia-pacific-14879982 Concern mounts for 'missing' penguin Happy Feet], BBC, 12 September 2011.</ref>

===Cultural references===
The species' unique life cycle in such a harsh environment has been described in print and visual media.{{sfn|Müller-Schwarze|1984|pp=28–29}}<ref>{{cite news|url=https://books.google.com/books?id=AXg1AAAAIBAJ&pg=PA21&dq=emperor+penguin+harsh&article_id=4534,2908208&hl=en&sa=X&redir_esc=y#v=onepage&q=emperor%20penguin%20harsh&f=false|title=Rulers of the icy kingdom|newspaper=[The Nation](/source/The_Nation)|date=9 January 1997|access-date=13 April 2026}}</ref> Widely distributed in cinemas in 2005, the French documentary {{Lang|fr|La Marche de l'empereur}}, which was also released with the English title ''[March of the Penguins](/source/March_of_the_Penguins)'', told the story of the penguins' reproductive cycle.<ref name=BBCBowes>{{cite news|url=https://news.bbc.co.uk/2/hi/entertainment/4165858.stm|title=Penguin secrets captivate US viewers|access-date=23 March 2008|author=Bowes P|date=19 August 2005|work=BBC website|publisher=British Broadcasting Corporation}}</ref><ref>{{cite web|url=http://empereur.luc-jacquet.com/index_flash.htm|title=La Marche de l'empereur, un film de Luc Jacquet|access-date=19 March 2008|work=Official Site|language=fr|archive-url=https://web.archive.org/web/20080306104835/http://empereur.luc-jacquet.com/index_flash.htm|archive-date=6 March 2008}}</ref> The animated movie ''[Happy Feet](/source/Happy_Feet)'' (2006, followed by a sequel ''[Happy Feet Two](/source/Happy_Feet_Two)'', 2011) features emperor penguins as its primary characters, with one in particular that loves to dance; although a comedy, it too depicts their life cycle and promotes an underlying serious environmental message of threats from global warming and depletion of food sources by overfishing.<ref>{{cite web|url=http://news.nationalgeographic.com/news/2006/11/061116-happy-feet.html|archive-url=https://web.archive.org/web/20061208000708/http://news.nationalgeographic.com/news/2006/11/061116-happy-feet.html|archive-date=8 December 2006|title="Happy Feet": Movie Magic vs. Penguin Truths|access-date=26 March 2008|author=Lovgren S|date= 16 November 2006|work=National Geographic website|publisher=National Geographic}}</ref> The animated movie ''[Surf's Up](/source/Surf's_Up_(film))'' (2007) features a surfing emperor penguin named Zeke "Big-Z" Topanga.<ref>{{cite web|url=http://kids.nationalgeographic.com/Stories/WackyStories/Surfs-up|title=Behind the Scenes of the New Movie "Surf's Up"|access-date=26 March 2008|author=Lovgren S|year=2007|work=National Geographic website|publisher=National Geographic |archive-url = https://web.archive.org/web/20080310002959/http://kids.nationalgeographic.com/Stories/WackyStories/Surfs-up |archive-date = 10 March 2008}}</ref> More than 30 countries have depicted the bird on their stamps—Australia, Great Britain, Chile and France have each issued several.<ref>{{cite web|url=http://www.birdtheme.org/mainlyimages/index.php?comb=7002000&s=7|title=Penguins Spheniscidae|access-date=29 March 2008|author=Scharning K|year=2008|work=Theme Birds on Stamps|publisher=self}}</ref> It has also been depicted on a 1962 10 [franc](/source/Belgian_franc) stamp as part of an Antarctic expedition series.<ref>{{cite web|url=http://www.birdtheme.org/country/belgium.html|title=Bird stamps from Belgium|access-date=29 March 2008|author=Scharning K|year=2008|work=Theme Birds on Stamps|publisher=self}}</ref>

==Notes==
{{Reflist|30em}}

==References==
* {{Cite book |last=Williams |first=Tony D. |title=The Penguins |year=1995 |publisher=Oxford University Press |location=Oxford, England |isbn=978-0-19-854667-2 }}
* {{cite book|last=Müller-Schwarze|first=Dietland|title=The Behavior of Penguins: Adapted to Ice and Tropics|publisher=[SUNY Press](/source/SUNY_Press)|date=1 January 1984|isbn=978-0-87395-866-0|url=https://books.google.co.uk/books?id=mJtX-0jc4uMC&newbks=0&printsec=frontcover&pg=PA28&dq=emperor+penguin+harsh+environment+life+cycle&hl=en&redir_esc=y#v=onepage&q=emperor%2520penguin%2520harsh%2520environment%2520life%2520cycle&f=false}}
* {{cite book |last1=Kooyman |first1=Gerald L. |title=[Journeys with Emperors: Tracking the World's Most Extreme Penguin](/source/Journeys_with_Emperors%3A_Tracking_the_World's_Most_Extreme_Penguin) |last2=Mastro |first2=Jim |date=November 2023 |publisher=University of Chicago Press |isbn=978-0-226-82438-3 |page=256 |ref=none}}

==External links==
{{Commons category|Aptenodytes forsteri}}
{{Wikispecies|Aptenodytes forsteri}}
* [https://animaldiversity.org/accounts/Aptenodytes_forsteri/ University of Michigan info site] with citations for specific studies
* [https://www.gdargaud.net/Antarctica/Penguins.html Photographs of Emperor penguins]
* [https://digimorph.org/specimens/Aptenodytes_forsteri/juvenile/whole/ Morphology of the emperor penguin] including 3D computed tomographic (CT) animations of skeletons
* {{cite web|url =http://www.photovolcanica.com/PenguinSpecies/Emperor/EmperorPenguinPhotos.html| title = Emperor Penguin|publisher = Photo Volcaniaca| author = Roscoe, R|access-date = 13 April 2008}}
* [https://search.macaulaylibrary.org/catalog?taxonCode=emppen1 Emperor penguin videos, photos & sounds] on the Internet Bird Collection

{{Penguins}}
{{Taxonbar|from=Q161829}}
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Emperor
Emperor penguin
Category:Birds of Antarctica
Emperor penguin
emperor penguin
Category:Articles containing video clips

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Adapted from the Wikipedia article [Emperor penguin](https://en.wikipedia.org/wiki/Emperor_penguin) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Emperor_penguin?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.