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What the sources say

Adélie PenguinPygoscelis adeliae

Every figure, record and mechanism on the Adélie Penguin profile was written from a source, and this is the working table behind it: 61 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

Australian Antarctic Division, Australian Government

Adélie penguin. Australian Antarctic Division, Australian Government.

The page saysThe pebble-stealing penguin
The source saysStealing rocks from other penguins, that's a major thing that they do.Note: tagline
The page saysAt 70 cm tall and 3 to 6 kg
The source saysAdélie penguins are medium sized penguins, weighing 3 to 6 kg and standing 70 cm tall.
The page saysis a medium-sized penguin and a very determined long-distance walker
The source saysThey are also very determined and successful long distance walkers travelling across many kilometres of fast ice on the return journey to their colonies.Note: "many" qualifies the kilometres walked, not the determination; paraphrase
The page saysIt is one of only 5 penguin species that live on the Antarctic continent
The source saysAdélie penguins are one of only 5 species of penguins that live on the Antarctic continent (Adélie, emperor , gentoo , chinstrap and macaroni penguins).
The page saysit breeds around the entire coast and its small islands, wherever there is exposed rock
The source saysAdélie penguins breed around the entire Antarctic coast and small islands in places where there is exposed rock.
The page saysAdélies have a life expectancy of 10 to 20 years
The source saysAdélie penguins have a life expectancy of 10 to 20 years.
The page saysOn the ice an Adélie walks at an average 2.5 km/h
The source saysTheir walking speed on ice averages 2.5 km/h
The page sayswhen there is enough snow, flops onto its belly and toboggans
The source saysWhen enough snow covers the ice, they prefer to plonk onto their bellies and toboggan.
The page saysIn the water it swims at 4 to 8 km/h
The source saysswimming speed 4 to 8 km/h
The page saysSome Adélies can dive to depths of up to 175 metres, though they usually feed in the top 70 metres
The source saysSome Adélie penguins are capable of diving to depths of up to 175 m but usually feed within the upper 70 m of the water column.
The page saysParents feeding chicks swim 5 to 120 km offshore on trips lasting 5 to 72 hours
The source saysBreeding adults swim between 5 to 120 km offshore to catch food for their chicks. Feeding trips range from 5 to 72 hours in duration.
The page saystracking shows these penguins can swim more than 1,200 km from their breeding site
The source saysScientists are tracking their routes so they can find out exactly where the Adélies go on their long sea journeys. So far, scientists know that these penguins can swim more than 1,200 km away from their breeding site.
The page saysLeopard seals are their main predators
The source saysTheir main predators are leopard seals
The page saysAdélies build their nests from pebbles on sloping ground, so meltwater runs away from the nest
The source saysIn spring, Adélie penguins build nests out of the pebbles they find on dry land. They choose a sloping site so that, when the snow melts, water runs away from the nest.
The page saysA researcher who followed 450 nests in camera photos
The source saysFrom the photos, she recorded the breeding success of 450 Adelie penguin nests.
The page sayssaid stealing rocks from other penguins is "a major thing that they do."
The source saysStealing rocks from other penguins, that's a major thing that they do.
The page saysThe more rocks a nest held, the better the chance of one or more chicks surviving
The source saysThe more rocks in the nest, the better the chance of one or more chicks surviving.
The page saysAntarctic coasts and offshore islands, nesting on bare, ice-free rock
The source saysAdélie penguins breed around the entire Antarctic coast and small islands in places where there is exposed rock.Note: stats.habitat; AAD's breeding transcript also gives 'ice-free land, snow-free land'
The page sayssome can dive to depths of up to 175 meters
The source saysSome Adélie penguins are capable of diving to depths of up to 175 m but usually feed within the upper 70 m of the water column.Note: stats.superpower
The page saysAdélies build their nests out of pebbles on sloping ground, so that meltwater runs away from the nest
The source saysIn spring, Adélie penguins build nests out of the pebbles they find on dry land. They choose a sloping site so that, when the snow melts, water runs away from the nest.Note: faq 1
The page saysthe higher a nest sits off the ground, the more likely it is to stay clear of snow and moisture
The source saysSo the higher the nest's off the ground, the more likely they are to be away from the snow cover and the moisture on the ground.Note: faq 1
The page saysIn a camera study of 450 nests
The source saysFrom the photos, she recorded the breeding success of 450 Adelie penguin nests.Note: faq 1
The page saysthe more rocks a nest held, the better the chance of one or more chicks surviving
The source saysThe more rocks in the nest, the better the chance of one or more chicks surviving.Note: faq 1
The page saysstealing rocks from other penguins is a major thing that they do
The source saysStealing rocks from other penguins, that's a major thing that they do.Note: faq 1
The page sayssteals rocks from other penguins to build its nest
The source saysStealing rocks from other penguins, that's a major thing that they do.

Source
02

Animal Diversity Web, University of Michigan

Pygoscelis adeliae (Adelie penguin). Animal Diversity Web, University of Michigan.

The page sayscan porpoise, shooting out to skim above the surface and grabbing a quick breath while it is out of the water
The source saysAdelie penguins can porpoise, or shoot out of the water to skim above the surface a few feet before splashing back down. While penguins are out of the water they quickly grab a breath of air.
The page saysfish and amphipods are part of the diet too
The source saysThey also consume fish, such as lantern fish and other members of the family Myctophidae and Antarctic silverfish (Pleuragramma antarcticum). Squid, other cephalopods, and amphipods are part of their normal diet as well.
The page saysAshore, a penguin is safe from them, because leopard seals only come ashore to sleep or rest
The source saysLeopard seals are never an issue for penguins on shore, because leopard seals only come ashore to sleep or rest.
The page saysAntarctic krill, fish such as Antarctic silverfish, and amphipods
The source saysThe primary food source for Adelie penguins is krill (Euphausia superba). They also consume fish, such as lantern fish and other members of the family Myctophidae and Antarctic silverfish (Pleuragramma antarcticum). Squid, other cephalopods, and amphipods are part of their normal diet as well.Note: stats.diet
The page saysporpoises out of the water to grab a breath
The source saysAdelie penguins can porpoise, or shoot out of the water to skim above the surface a few feet before splashing back down. While penguins are out of the water they quickly grab a breath of air.

Source
03

Borowicz et al. 2018

Borowicz et al. (2018). Multi-modal survey of Adélie penguin mega-colonies reveals the Danger Islands as a seabird hotspot. Scientific Reports.

The page saysA drone and ground survey published in 2018
The source saysa multi-modal survey consisting of direct ground counts and computer-automated counts of unmanned aerial vehicle (UAV) imageryNote: UAV = drone; 2018 is the paper's publication year (the reference's year field); the fieldwork was in the 2015/16 season, so the text says 'published in'
The page sayscounted 751,527 breeding pairs on the Danger Islands alone, more than the rest of the Antarctic Peninsula region combined, including what were then the third and fourth largest Adélie colonies in the world
The source saysthe Danger Islands host 751,527 pairs of Adélie penguins, more than the rest of AP region combined, and include the third and fourth largest Adélie penguin colonies in the world.Note: rank scoped to the 2018 paper with 'what were then'

Source
04

Fragão et al. 2021

Fragão et al. (2021). Microplastics and other anthropogenic particles in Antarctica: Using penguins as biological samplers. Science of The Total Environment.

The page saysIn droppings collected across the Antarctic Peninsula and Scotia Sea
The source sayswere selected to evaluate the occurrence of microplastics across the Antarctic Peninsula and Scotia Sea. Scat samples (used as a proxy of ingestion), were collected from breeding colonies over seven seasons between 2006 and 2016.Note: scat = droppings
The page saysAntarctic krill turned up in 85% of Adélie samples
The source saysAntarctic krill (Euphausia superba), present in scat samples, contributed 85%, 66% and 54% of the diet in terms of frequency of occurrence to the diet of Adélie, gentoo and chinstrap penguins, respectively.Note: frequency of occurrence = share of samples it turned up in; 85% is the Adélie figure

Source
05

Emlen & Penney 1964

Emlen & Penney (1964). Distance navigation in the Adelie penguin. Ibis.

The page sayssteers across featureless ice by the sun
The source saysthe birds possessed a navigation mechanism which used the sun as the primary orientation cue plus a biological clock to compensate for changing sun azimuth positionsNote: tagline; the 1964 experiment is scoped in the body
The page saysIn a study published in 1964, male Adélies carried from coastal colonies to featureless ice plateaus inland
The source saysMale Adelie penguins Pygoscelis adeliae were transported from coastal rookeries in the Ross Sea area of Antarctica to three release points on featureless ice plateaux in the interior of the continent.Note: 1964 is the paper's publication year (the reference's year field)
The page saysset off in straight lines when conditions were good
The source saysBirds released inland from a coastal rookery under favourable conditions consistently moved in straight courses N.N.E. toward the coast.
The page saysBirds from the same colony held the same heading wherever they were released
The source saysThe mechanism effected a consistent escape direction for birds of a given population (source) regardless of the location of the release site.
The page sayseven when it did not point home
The source saystook courses essentially parallel to this departure direction, i.e., northwest and northeast respectively on a meridian scale rather than true north or in the homeward direction
The page saysThe researchers concluded that the penguins steer by the sun, using a biological clock to allow for its changing position
The source saysthe birds possessed a navigation mechanism which used the sun as the primary orientation cue plus a biological clock to compensate for changing sun azimuth positionsNote: "allow for" paraphrases "compensate for"
The page saysthis could guide lost birds toward feeding areas off the coast
The source saysIt is considered to have survival value in the present instance in steering lost penguins to the appropriate off‐coast feeding areas
The page saysSteers by the sun across featureless ice
The source saysthe birds possessed a navigation mechanism which used the sun as the primary orientation cue plus a biological clock to compensate for changing sun azimuth positionsNote: stats.superpower
The page saysWith the sun.
The source saysthe birds possessed a navigation mechanism which used the sun as the primary orientation cue plus a biological clock to compensate for changing sun azimuth positionsNote: faq 2
The page saysIn a study published in 1964, male Adélies carried from coastal colonies to featureless ice plateaus inland moved in straight lines
The source saysMale Adelie penguins Pygoscelis adeliae were transported from coastal rookeries in the Ross Sea area of Antarctica to three release points on featureless ice plateaux in the interior of the continent. ... Birds released inland from a coastal rookery under favourable conditions consistently moved in straight courses N.N.E. toward the coast.Note: faq 2; 1964 is the paper's publication year (the reference's year field)
The page saysbirds from the same colony held the same heading wherever they were released
The source saysThe mechanism effected a consistent escape direction for birds of a given population (source) regardless of the location of the release site.Note: faq 2
The page saysThe researchers concluded that the birds use the sun as their main cue, with a biological clock to allow for the sun's changing position
The source saysthe birds possessed a navigation mechanism which used the sun as the primary orientation cue plus a biological clock to compensate for changing sun azimuth positionsNote: faq 2; "allow for" paraphrases "compensate for"

Source
06

Chappell, Morgan & Bucher 1990

Chappell, Morgan & Bucher (1990). Weather, microclimate, and energy costs of thermoregulation for breeding Adélie Penguins. Oecologia.

The page saysfasts for weeks on end
The source saysAdults arrive at colonies in October and fast for 3~4 weeks while establishing territories, courting, and making nests.Note: tagline; 3 to 4 weeks, stated in the body
The page saysAdults arrive at their colonies in October and fast for 3 to 4 weeks while they claim territory, court and build nests
The source saysAdults arrive at colonies in October and fast for 3~4 weeks while establishing territories, courting, and making nests.
The page saysOnce the eggs are laid, females feed at sea while males fast for another 10 to 16 days through the first incubation shift
The source saysFemales feed at sea after laying their eggs (usually two), but males continue fasting for another 10-16 days during the first incubation shift.Note: "usually" qualifies the clutch size (two eggs), which the text does not state

Source
07

Descamps, Cristea & Aspnes 2026

Descamps, Cristea & Aspnes (2026). An Adélie penguin (Pygoscelis adeliae) 200 km from the sea. Polar Research.

The page saysSometimes things still go wrong, and a penguin may become disoriented
The source sayssometimes things can go wrong and penguins may occasionally become disoriented
The page saysOn 5 January 2026, an Adélie was seen near Troll Research Station in Dronning Maud Land, 200 km from the nearest open sea and about 1,300 km from the closest breeding colony
The source saysOn 5 January 2026 in the morning (08:00), an Adélie penguin was observed near Troll Research Station, Dronning Maud Land, Antarctica (Fig. 1a). The nearest access to open sea was 200 km away (Fig. 1b), and the closest breeding colony—in Lützow-Holmbukta (Lützow-Holm Bay)—is about 1300 km away
The page saysIt appeared to be in good condition
The source saysThe bird appeared to be in good physical condition
The page saysstayed among the station buildings until 3 pm, then walked east and disappeared
The source saysIt then walked towards the station and stayed there, among the buildings, until 15:00. It then walked eastwards and disappeared.Note: 15:00 = 3 pm
The page saysThe scientists who reported it know of only one comparable peer-reviewed record: Adélie tracks found 300 km from the coast in 1958
The source saysTo our knowledge, the only comparable peer-reviewed record of extreme inland movement of an Adélie penguin comes from Sladen & Ostenso (1960), who reported Adélie penguin tracks located 300 km from the coast in 1958

Source
08

Ainley et al. 2005

Ainley et al. (2005). Leopard seal predation rates at penguin colonies of different size. Antarctic Science.

The page saysin a six-year study most of the seals' hunting took place near the beach
The source sayswe investigated the predation rates on penguins by leopard seals (Hydrurga leptonyx) over a period of six years ... The number of seals present varied directly with the amount of penguin traffic in the areas near the beach, where most predation takes place.
The page saysIt appears to.
The source saysWith respect to predation, it appears to be advantageous for Adélie penguins to nest in very small or very large colonies.Note: faq 3; answers the question with the paper's own hedge
The page saysIn a six-year study, leopard seals were present persistently only when more than about 250 penguins an hour passed through the area near the beach
The source sayswe investigated the predation rates on penguins by leopard seals (Hydrurga leptonyx) over a period of six years ... The number of seals present varied directly with the amount of penguin traffic in the areas near the beach, where most predation takes place. Seals were present persistently only when penguin traffic exceeded about 250 penguins per hour.Note: faq 3
The page sayspredation rates varied with that traffic in a curve that levelled off above about 1,200 penguins an hour
The source saysPredation rates also varied with penguin traffic in a curvilinear fashion, leveling off where traffic exceeded about 1200 penguins per hour.Note: faq 3; "above" paraphrases "exceeded"
The page saysAt large colonies, so many penguins come and go that they swamp the seals' efforts, which reduces each bird's chance of being taken, and small colonies are of little interest to the seals
The source saysAt large colonies, the number of penguins moving to and from the colony ‘swamp’ the seals' predatory efforts, thus reducing the chances that an individual penguin will be taken. Small colonies are of little interest to the seals.Note: faq 3; paraphrase of "the number of penguins moving to and from the colony swamp the seals' predatory efforts"
The page saysas far as predation goes, it appears to pay to nest in a very small or a very large colony
The source saysWith respect to predation, it appears to be advantageous for Adélie penguins to nest in very small or very large colonies.Note: faq 3

Source
09

The IUCN Red List of Threatened Species 2020

Pygoscelis adeliae. The IUCN Red List of Threatened Species 2020: e.T22697758A157660553.

The page saysLeast Concern
The source saysIUCN Red List category: Least Concern (LC).Note: stats.conservationStatus, via GBIF's copy of the Red List

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.