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Emperor PenguinAptenodytes forsteri

Every figure, record and mechanism on the Emperor Penguin profile was written from a source, and this is the working table behind it: 57 claims checked word for word against these sources. The left column is what the page says. The right column is the source's own words, copied, not paraphrased; a ... marks a cut and[brackets] an insertion. Open any source and check it yourself.

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Source
01

Animal Diversity Web, University of Michigan

Aptenodytes forsteri (emperor penguin). Animal Diversity Web, University of Michigan.

The page saysEmperor penguins stand 101 to 132 centimeters tall
The source saysstanding 101 to 132 cm tall
The page saysThey gain and lose weight rapidly across the breeding and feeding seasons
The source saysThey gain and lose weight rapidly during breeding and feeding seasons.
The page sayseating mostly fish, crustaceans and molluscs
The source saysEmperor penguins are carnivorous and primarily feed on fish, crustaceans, and molluscs.
The page saysfrom the waters around Antarctica
The source saysThey feed in the open waters of the ocean surrounding Antarctica, or underneath sea ice.
The page saysWhich prey is plentiful varies from place to place, but some research has found Antarctic silverfish among their most frequently eaten
The source saysPrey abundance varies from location to location, but some research has found that the Antarctic silverfish (Pleuragramma antarcticum) is one of the most frequently consumed species.
The page sayswith Nototheniidae fish a staple
The source saysFish from the family Nototheniidae are also consumed as a staple of their diet.
The page saysAntarctic krill and glacial squid eaten regularly
The source saysMolluscs such as the glacial squid (Psychroteuthis glacialis), hooked squid (Kondakovia longimana), and the Antarctic krill (Euphausia superba) are also eaten regularly.
The page saysAntarctic krill
The source saysthe Antarctic krill (Euphausia superba) are also eaten regularly.
The page saysglacial squid
The source saysMolluscs such as the glacial squid (Psychroteuthis glacialis), hooked squid (Kondakovia longimana), and the Antarctic krill (Euphausia superba) are also eaten regularly.
The page saysA rough, spiky-textured tongue helps them catch and eat slippery fish and squid
The source saysEmperor penguins have a rough and spiky-textured tongue, which helps them catch and eat slippery fish and squids more easily.
The page saysbreed along the Antarctic coastline between 66 and 78 degrees south
The source saysIn breeding months (April to November), emperor penguin colonies are found between 66° and 78° south latitude, along the Antarctic coastline.
The page sayswinter temperatures fall as low as minus 40 degrees Celsius with wind chills reaching minus 60
The source saysWinter temperatures there range from -40 to 0°C, with wind chills reaching -60°C.
The page saysKiller whales and leopard seals have been seen preying on emperor penguins
The source saysKiller whales (Orcinus orca) have been observed to prey on emperor penguins, sometimes harassing them for fun. ... Leopard seals (Hydrurga leptonyx) are also marine predators of penguins, and have been observed to kill emperor penguins.Note: 'sometimes' qualifies the harassment clause, which the page does not repeat; 'adults' and 'in open water' were cut because the source names neither
The page saysskuas are known to steal and eat their eggs and chicks
The source saysSeabirds called skuas (Stercorarium parasiticus) are also known to steal and eat emperor penguin eggs and chicks.
The page saysMost dives are shallow and fairly quick, which makes it harder for predators to reach them
The source saysMost emperor dives are shallow and fairly quick, which makes it harder for predators to reach them before they are out of the water again.
The page sayscountershading, a dark back and pale belly, makes swimming penguins harder to make out
The source saysWith black backs and white bellies, emperor penguins are countershaded. This makes it harder to distinguish their form while they are swimming.
The page saysBreeding starts just as the Antarctic winter does: penguins arrive at their breeding grounds on the sea ice in early to mid-April
The source saysPenguins arrive at breeding grounds on sea-ice in early-mid April at the onset of the Antarctic winter.Note: 'penguins arrive', not 'pairs arrive': AAD describes pairs forming or re-forming at the colony
The page saysFemales lay a single egg in late April or May and pass it to their mate almost immediately
The source saysFemales lay a single egg in late April or May and pass the egg off to their mate almost immediately.
The page saystravel about 50 to 120 kilometers back to open water to feed
The source saysFemales then travel approximately 50 to 120km back to the ocean to find food.
The page sayscalled a brood pouch, low on the belly
The source saysMales incubate and protect eggs in their brood pouches, a specialized skin fold on their lower abdomens.
The page saysChicks hatch in mid-July
The source saysChicks hatch in mid-July, weighing about 315 grams.Note: hatch weight cut: ADW's 315 g and AAD's 150 to 200 g disagree
The page saysTheir mother's return can come before hatching or as much as a month after it
The source saysDepending on how far mothers have to travel for food, their return may be before the chicks hatch or up to a month thereafter.Note: 'as much as a month after it' = 'up to a month thereafter'
The page saysthe father feeds them a nutrient-rich, milky substance he produces in his own esophagus until she is back
The source saysMales feed hatchlings by producing a nutrient-rich, milky substance in their esophagus until females return.
The page saysAntarctic wind chills down to minus 60
The source saysWinter temperatures there range from -40 to 0°C, with wind chills reaching -60°C.
The page saysAntarctic silverfish, Nototheniidae fish, Antarctic krill, and glacial squid
The source saysthe Antarctic silverfish (Pleuragramma antarcticum) is one of the most frequently consumed species. Fish from the family Nototheniidae are also consumed as a staple of their diet. Molluscs such as the glacial squid (Psychroteuthis glacialis) ... and the Antarctic krill (Euphausia superba) are also eaten regularly.
The page saysAntarctic coastal sea ice, pack ice, and the surrounding Southern Ocean
The source saysDuring their breeding season, emperor penguins congregate on dense stable ice attached to the coastline of Antarctica. ... Outside of breeding season, they spend most of their time in seasonally-packed ice zones, where open sea is easily available for foraging.
The page saysA rough, spiky-textured tongue helps them catch and eat slippery prey.
The source saysEmperor penguins have a rough and spiky-textured tongue, which helps them catch and eat slippery fish and squids more easily.
The page saysWild emperors typically live 15 to 20 years
The source sayslifespan expectancy in the wild of 15 to 20 years

Source
02

Meir & Ponganis 2009

Meir & Ponganis (2009). High-affinity hemoglobin and blood oxygen saturation in diving emperor penguins. Journal of Experimental Biology.

The page sayscan dive deeper than 500 meters and stay under for more than 23 minutes
The source saysdiving to depths greater than 500 m and for durations longer than 23 minNote: 'deeper than' paraphrases 'greater than' for a depth figure; same meaning, no added strength
The page saysOne reason is their hemoglobin, the protein that carries oxygen in blood, which holds onto oxygen unusually tightly, like that of high-altitude birds and other penguins
The source saysTo examine mechanisms underlying the exceptional diving ability of this species ... This investigation revealed enhanced Hb-O2 affinity (P50=28 mmHg, pH 7.5) in the emperor penguin, similar to high-altitude birds and other penguin speciesNote: 'one reason' rests on the study framing the affinity as a mechanism underlying diving ability; 'unusually tightly' glosses 'enhanced'; the source's own comparison now names other penguins too, so the trait is not presented as unique
The page saysThat lets a diving penguin carry more oxygen when blood oxygen runs low and use up more of the oxygen it breathed in before the dive
The source saysThis allows for increased O2 at low blood PO2 levels during diving and more complete depletion of the respiratory O2 store.Note: 'the oxygen it breathed in before the dive' glosses 'the respiratory O2 store'
The page saysThe blood in its arteries stays almost fully saturated with oxygen through much of a dive, and only drops significantly on the final climb to the surface
The source saysarterial SO2 levels are maintained near 100% throughout much of the dive, not decreasing significantly until the final ascent phaseNote: scoped to arterial blood: the same abstract says venous blood O2 was nearly completely depleted in longer dives. 'almost fully' = 'near 100%'; 'only drops significantly on the final climb' = 'not decreasing significantly until the final ascent phase'
The page saysdives past 500 meters
The source saysdiving to depths greater than 500 m
The page saysDives deeper than 500 meters and longer than 23 minutes, with hemoglobin that grips oxygen unusually tightly
The source saysdiving to depths greater than 500 m and for durations longer than 23 min ... enhanced Hb-O2 affinityNote: two facts side by side: the saturation profile was not measured on 500 m dives, so the old 'keeping blood almost fully saturated through dives deeper than 500 meters' was cut
The page saysEmperor penguins can dive to depths greater than 500 meters and stay under for more than 23 minutes.
The source saysdiving to depths greater than 500 m and for durations longer than 23 min
The page saysTheir hemoglobin, the protein that carries oxygen in blood, holds onto oxygen unusually tightly, like that of high-altitude birds and other penguins, and the blood in their arteries stays almost fully saturated with oxygen through much of a dive.
The source saysenhanced Hb-O2 affinity (P50=28 mmHg, pH 7.5) in the emperor penguin, similar to high-altitude birds and other penguin species ... arterial SO2 levels are maintained near 100% throughout much of the diveNote: the two facts are joined by 'and', not 'which keeps': the abstract does not say the affinity causes the saturation profile

Source
03

Ponganis et al. 2003

Ponganis et al. (2003). Regional heterothermy and conservation of core temperature in emperor penguins diving under sea ice. Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology.

The page saysA diving penguin's wings run cold
The source saysgrand mean temperatures in the wing vein, foot vein and lumbar subcutaneous tissue during dives were 7.6+/-0.7 degrees C (n=157 dives in three birds) ... the observed decreases in limb, anterior abdomen, subcutaneous and sub-feather temperatures
The page saysIn a study of emperors diving from an isolated hole in the sea ice
The source saysTemperatures were recorded at several body sites in emperor penguins (Aptenodytes forsteri) diving at an isolated dive holeNote: 'sea ice' is the paper's own title: 'Regional heterothermy and conservation of core temperature in emperor penguins diving under sea ice'
The page saysthe average temperature inside a wing vein during dives was about 7.6 degrees Celsius
The source saysgrand mean temperatures in the wing vein, foot vein and lumbar subcutaneous tissue during dives were 7.6+/-0.7 degrees C (n=157 dives in three birds)
The page sayswhile the stomach averaged 37.1 and the chest muscle 37.8
The source saysGrand mean temperatures (+/-S.E.) in central body sites during dives were: stomach: 37.1+/-0.2 degrees C (n=101 dives in five birds), pectoral muscle: 37.8+/-0.1 degrees C (n=71 dives in three birds)
The page saysThose readings fit a warm core and a cooled outer shell, caused by narrowed blood vessels near the body's surface (peripheral vasoconstriction), feathers that insulate less during a dive, and heat lost to the water
The source saysSuch high temperatures within the body and the observed decreases in limb, anterior abdomen, subcutaneous and sub-feather temperatures are consistent with preservation of core temperature and cooling of an outer body shell secondary to peripheral vasoconstriction, decreased insulation of the feather layer, and conductive/convective heat loss to the water environment during the diving of these emperor penguins.Note: 'fit' = 'are consistent with'; 'caused by' = 'secondary to'; all three of the source's causes are named, not vasoconstriction alone

Source
04

Australian Antarctic Program

Emperor penguin breeding cycle. Australian Antarctic Program.

The page saysaround hatching time, adults weigh 22 to 30 kilograms
The source saysThe chicks are very small when they hatch weighing only about 150 g to 200 g (adult penguins weigh 22 kg to 30 kg at this time of year).Note: replaces ADW's '25 to 45 kg as adults', whose low end the AAD figure and Robin et al.'s 18 kg leanest males both contradict
The page saysbefore their yearly molt they have to almost double their body mass
The source saystend to go out to sea at this time to start fattening up for their annual moult ... Adults have to almost double their body mass before the moult.
The page saysMales hold the egg on top of their feet inside a fold of warm skin called a brood pouch, low on the belly, for roughly 65 to 75 days until it hatches
The source saysgives the egg to her partner who carefully puts it on his feet and covers it with a skin fold. In this way the egg is kept toasty warm ... It takes 65 to 75 days for the eggs to hatchNote: 'until it hatches' restates 'for the eggs to hatch' as a duration. 'bare' was cut: neither AAD nor ADW says it
The page saysmonths of fasting
The source saysIt takes 65 to 75 days for the eggs to hatch - by the time the chicks appear, their fathers have fasted for 4 months!Note: 'appear' is the source's word for hatching, not a hedge on the fast
The page saysA male holds the single egg on top of his feet inside a warm fold of skin called a brood pouch
The source sayseventually the female produces a single egg ... carefully puts it on his feet and covers it with a skin fold. In this way the egg is kept toasty warm ... they fit comfortably in the brood pouch
The page saysfor roughly 65 to 75 days until it hatches, fasting the entire time and living entirely off body fat he laid down over the summer
The source saysThe males cannot go out and feed with the egg on their feet. It takes 65 to 75 days for the eggs to hatch ... The males rely entirely on the body fat that they laid down during summer to survive the long winter fast.Note: 'until it hatches' restates 'for the eggs to hatch' as a duration
The page saysBy the time the female returns, he has lost nearly half his body mass
The source saysWhen the females finally return to the colony in July the males have lost nearly half their body mass and look quite skinny.
The page saysDuring winter storms, males huddle closely together to keep warm.
The source saysthe males stay behind to incubate the eggs. During the winter storms they huddle closely together to keep warm.Note: replaces an ADW description under an FAQ whose ref is AAD
The page saysfor a bird whose male stands with the egg on his feet for 65 to 75 days, unable to leave it to feed
The source sayscarefully puts it on his feet and covers it with a skin fold. ... The males cannot go out and feed with the egg on their feet. It takes 65 to 75 days for the eggs to hatchNote: vibe.reason, settle #173: replaces "awe-inspiring Antarctic endurance", a place and a mood; the music description is unchanged

Source
05

Australian Antarctic Program

Emperor penguins. Australian Antarctic Program.

The page saysthough some pass 40
The source saysSome emperors live to more than 40 years but most do not live that long in the wild

Source
06

Robin et al. 1988

Robin et al. (1988). Protein and lipid utilization during long-term fasting in emperor penguins. American Journal of Physiology-Regulatory, Integrative and Comparative Physiology.

The page saysAcross the four-month winter fast, a male starts at about 38 kilograms, and the leanest are down to an estimated 18 by the time they head back to sea to feed
The source saysThe body mass of male emperor penguins is approximately 38 kg at the beginning of the 4-mo winter fast connected with breeding, and it is an estimated approximately 18 kg in leanest birds at time of spontaneous refeeding.Note: restores 'estimated' and 'leanest birds'; the end point is refeeding, not hatching, and the fast starts at arrival, not pairing (AAD: 'since they arrived at the colony')

Source
07

Gilbert et al. 2006

Gilbert et al. (2006). Huddling behavior in emperor penguins: Dynamics of huddling. Physiology & Behavior.

The page saysTo save energy through the fast, males pack into huddles
The source saysAlthough huddling was shown to be the key by which emperor penguins (Aptenodytes forsteri) save energy and sustain their breeding fast during the Antarctic winter ... Throughout the breeding season, males huddled for 38+/-18% (S.D.) of their time
The page sayshuddles that can hold hundreds of birds at densities of up to 10 per square meter
The source saysThese huddles, formed during courtship and incubation in the colony, can be made up of more than hundreds of individuals, reaching densities of up to 10 birds per m 2Note: 'more than hundreds' is a lower bound, so the page says 'hundreds', not 'several hundred'
The page saysthe male alone incubates the egg
The source saysBoth mates starve for about 45 days during the pairing period, while males alone take on the task of incubation, which adds another 65 days to their fast

Source
08

The IUCN Red List of Threatened Species 2020

Aptenodytes forsteri. The IUCN Red List of Threatened Species 2020: e.T22697752A157658053.

The page saysNear Threatened
The source saysIUCN Red List category: Near Threatened (NT).
The page saysThe emperor penguin is listed as Near Threatened on the IUCN Red List.
The source saysIUCN Red List category: Near Threatened (NT).

How the table was made: a writer drafted the profile from these sources and logged each claim with its quote, a reviewer with nothing but this table checked every sentence said no more than its quote, and a script confirmed each quote appears word for word in the source. The method is in the site'sAbout page.