The great auk (Pinguinus impennis), also called the garefowl or penguin, was an extinct bird that could not fly. It first appeared about 400,000 years ago and disappeared in the mid-1800s. It was the only bird in its group called Pinguinus. It was not closely related to the penguins of the Southern Hemisphere, which got their name because they looked similar to the great auk.

The great auk lived on rocky, remote islands near the ocean where there was plenty of food. These islands were rare, so the great auk had few places to breed. During the non-breeding season, the bird swam in the North Atlantic, traveling as far south as northern Spain and along the coasts of Canada, Greenland, Iceland, the Faroe Islands, Norway, Ireland, and Great Britain.

The great auk was about 75 centimeters (29.5 inches) tall and weighed about 5 kilograms (11 pounds). It was the largest alcid to live in modern times and the second-largest alcid overall, after a prehistoric bird called Miomancalla. Its back was black, and its belly was white. The beak was black, heavy, and had grooves. In summer, the great auk had white patches over each eye. In winter, these patches disappeared, and a white band formed between the eyes. Its wings were only 15 centimeters (6 inches) long, so it could not fly. Instead, it was a strong swimmer, using this skill to hunt fish like Atlantic menhaden and capelin, as well as crustaceans. On land, the bird was clumsy. Great auk pairs stayed together for life. They nested in very large, social groups, laying one egg on bare rock. The egg was white with brown spots. Both parents helped keep the egg warm for about six weeks until the baby hatched. The young left the nest after two to three weeks, but the parents continued to care for them.

The great auk was important to Native American cultures, serving as a food source and a symbol. Some Maritime Archaic people were buried with great auk bones. One burial included a person covered with more than 200 great auk beaks, likely from a cloak made of their skins. Early European explorers hunted the great auk for food and as fishing bait, reducing its numbers. Its feathers were highly valued in Europe, leading to the extinction of European populations by the mid-1500s. By the 1500s, countries like Great Britain began protecting the bird with early environmental laws, but hunting continued.

As the great auk became rarer, European museums and collectors wanted its skins and eggs. On June 3, 1844, the last two confirmed great auks were killed on Eldey, near Iceland, ending the last known breeding attempt. Later reports of the bird are unconfirmed. A sighting in 1852 is considered the last known appearance of the species. The great auk is mentioned in several books, and the scientific journal of the American Ornithological Society was named The Auk (now called Ornithology) in its honor until 2021.

Taxonomy and evolution

Studying mitochondrial DNA sequences has confirmed findings from earlier research on the physical traits and geographical distribution of birds, showing that the razorbill is the closest living relative of the great auk. The great auk was also closely related to the little auk, or dovekie, which evolved very differently compared to Pinguinus. Because the great auk looked similar to the razorbill (except for its inability to fly and larger size), it was often placed in the genus Alca, as classified by Linnaeus.

The oldest known fossils of the modern great auk were found at the Boxgrove Palaeolithic site in England and the Lower Town Hill Formation in Bermuda. These fossils are at least 400,000 years old and date to the Middle Pleistocene. A Pliocene relative, Pinguinus alfrednewtoni, and genetic evidence suggest that the three closely related bird genera split from their common ancestor, a bird likely resembling a stout Xantus's murrelet, after it spread to the Atlantic coasts. By that time, the murres, or Atlantic guillemots, had already separated from other Atlantic alcids. Razorbill-like birds were common in the Atlantic during the Pliocene, but the evolution of the little auk is poorly documented. Genetic data support either possibility, but most evidence suggests placing the great auk in its own distinct genus. Some scientists still believe it belongs in the genus Alca. The great auk is the only British bird recorded as extinct in modern history.

A 2004 genetic study shows the great auk's placement among its closest relatives in the following order:
– Alle alle (little auk)
– Uria aalge (common murre)
– Uria lomvia (thick-billed murre)
– Alca torda (razorbill)
– Pinguinus impennis (great auk)
– Brachyramphus marmoratus (marbled murrelet)
– Brachyramphus brevirostris (Kittlitz's murrelet)
– Cepphus grylle (black guillemot)
– Cepphus columba (pigeon guillemot)
– Cepphus carbo (spectacled guillemot)

Pinguinus alfrednewtoni was a larger, flightless bird in the genus Pinguinus that lived during the Early Pliocene. Fossils from the Yorktown Formation in North Carolina suggest it split from the great auk and their shared ancestor. Pinguinus alfrednewtoni lived in the Western Atlantic, while the great auk lived in the Eastern Atlantic. After Pinguinus alfrednewtoni became extinct, the great auk took over its territory. The great auk was not closely related to other extinct flightless alcids like Mancalla, Praemancalla, and Alcodes.

The great auk was one of 4,400 animal species described by Carl Linnaeus in his 18th-century work Systema Naturae, where it was given the scientific name Alca impennis. The genus name "Alca" comes from a Scandinavian term for razorbills and their relatives. The bird was known in literature before this, with Charles d'Ecluse describing it in 1605 as Mergus Americanus, including a woodcut that is the oldest clear visual depiction of the bird.

The great auk was not placed in its own genus, Pinguinus, until 1791. The name Pinguinus comes from Spanish, Portuguese, and French terms for the bird, which in turn derive from the Latin word pinguis, meaning "plump." The species name impennis comes from Latin and refers to the lack of flight feathers, or pennae.

The Irish name for the great auk is falcóg mhór, meaning "big seabird/auk." The Basque name is arponaz, meaning "spearbill." Its early French name was apponatz, while modern French uses grand pingouin. The Norse called it geirfugl, meaning "spearbird," which led to the alternative English name "garefowl" or "gairfowl." The Inuit name was isarukitsok, meaning "little wing."

The word "penguin" first appeared in the 16th century as a synonym for "great auk." It may come from the Welsh phrase pen gwyn, meaning "white head," though this is debated. When European explorers discovered penguins in the Southern Hemisphere, they named them after the great auk due to their similar appearance, even though they are not closely related biologically. Whalers also referred to both northern and southern birds as "woggins."

Description

The great auk was a flightless bird that stood about 75 centimetres (29.5 in) tall and weighed around 5 kilograms (11 lb) as an adult. It was the second-largest bird in its family and the order Charadriiformes, only smaller than the mancalline Miomancalla. However, it was the largest species of its kind to survive into modern times. Great auks living farther north were generally larger than those in southern regions. Males and females had similar feather colors, but there were differences in size, especially in the bill and leg bones. The bird’s back was glossy black, and its belly was white. Its neck and legs were short, and its head and wings were small. In summer, the great auk had a wide white patch over each eye, with a hazel or chestnut-colored eye. Auks look similar to penguins because both have webbed feet and dark backs with light undersides, which evolved separately in water-dwelling birds. In winter, the great auk lost its eye patch, replacing it with a white band and a grey line of feathers from the eye to the ear. During summer, its chin and throat were blackish-brown, and its mouth was yellow. In winter, its throat turned white. Some birds had grey feathers on their sides, but details about this variation are unknown. The bird’s bill was large, 11 cm (4.3 in) long, and curved downward. It had deep white grooves in both the top and bottom parts of the bill—up to seven on the top and twelve on the bottom in summer, fewer in winter. Its wings were only 15 cm (5.9 in) long, and the longest feathers were 10 cm (3.9 in). Its feet and claws were black, and the webbing between its toes was brownish black. Its legs were positioned far back on its body, helping it swim and dive powerfully.

Baby great auks were described as grey and covered in soft feathers, but no preserved skins exist to confirm their exact appearance. Young birds had less pronounced grooves on their bills and had mottled white and black necks. They lacked the eye spot found in adults and instead had a grey line running through their eyes (which still had white rings) to just below their ears.

The great auk made low croaking sounds and a hoarse scream. A captured bird was seen making a gurgling noise when nervous. Other sounds are unknown, but they likely resembled those of the razorbill, only louder and deeper.

Distribution and habitat

The great auk lived in cold North Atlantic coastal waters near the coasts of Canada, the northeastern United States, Norway, Greenland, Iceland, the Faroe Islands, Great Britain, Ireland, France, and the Iberian Peninsula. Fossils from the Pleistocene era show the great auk also lived in Southern France, Italy, and other parts of the Mediterranean Basin. The farthest south the great auk was found in the eastern Atlantic is two bones from North Africa: one from Madeira and another from the Neolithic site of El Harhoura 2 in Morocco.

In the western Atlantic, great auk bones have been found as far south as Florida. These bones may have belonged to great auks that lived around 1000 BC, 1000 AD, and the 17th century. However, some scientists think some of the bones found in Florida might have come from aboriginal trading. In recorded history, the great auk rarely traveled farther south than Massachusetts Bay during winter. It was most common near the Grand Banks of Newfoundland, where the last great auk was seen in 1852.

The great auk only left the water to breed, even resting on the sea when not breeding. Breeding groups of the great auk were found from Baffin Bay to the Gulf of St. Lawrence, across the northern Atlantic, including Iceland, Norway, and the British Isles in Europe. To nest, great auks needed rocky islands with sloping shorelines that allowed easy access to the sea. These requirements were very limiting, and it is believed the great auk had no more than 20 breeding colonies. The nesting sites also needed to be near rich feeding areas and far enough from the mainland to avoid predators like humans and polar bears. Only seven former breeding colonies are known: Papa Westray in the Orkney Islands, St. Kilda near Scotland, Grimsey Island, Eldey Island, Geirfuglasker near Iceland, Funk Island near Newfoundland, and the Bird Rocks (Rochers-aux-Oiseaux) in the Gulf of St. Lawrence. Records suggest the great auk may have also bred on Cape Cod in Massachusetts. By the late 18th and early 19th centuries, the breeding range was limited to Funk Island, Grimsey Island, Eldey Island, the Gulf of St. Lawrence, and the St. Kilda Islands. Funk Island was the largest known breeding colony. After the chicks left the nest, great auks moved north and south away from the breeding areas, often traveling south during late autumn and winter.

Ecology and behaviour

The great auk was never seen or studied by scientists who lived during its time. People only know about it from stories told by non-scientists, like sailors. Because of this, scientists do not know much about how the great auk lived or behaved. However, scientists can guess some things about the great auk by studying its close living relative, the razorbill, and by looking at soft tissues that remained after the bird died.

Great auks walked slowly and sometimes used their wings to move over rough ground. When they ran, they moved in a stiff, straight line with short steps. Few animals hunted the great auk. These included large sea mammals, like orcas, and birds like white-tailed eagles. Polar bears also hunted great auks that were nesting. A scientist named Otto Fabricius observed the great auk and noted that some birds were calm and easy to approach, while others were harder to get close to. He thought this might be because of the birds’ age. Humans also hunted great auks for food, their feathers, and to keep them in museums and private collections. Great auks were not easily scared by sights, but they did react to sounds. They used their beaks to fight when they were near other birds or when humans tried to catch them. Scientists believe the great auk lived about 20 to 25 years. In winter, they traveled south, either in pairs or small groups, but never with their entire nesting group.

The great auk was a strong swimmer. It used its wings to move underwater, keeping its head up but its neck bent. It could turn, move sideways, and change direction underwater. It could dive to depths of 75 meters, and some say it could go as deep as 1 kilometer. Most dives were shallow to save energy. It could hold its breath for 15 minutes, longer than a seal. This ability helped it avoid competition with other birds. The great auk could speed up underwater and then jump out of the water to land on rocks above the ocean.

The great auk usually hunted in shallow water where fish swam in groups. After breeding, they were sometimes seen as far as 500 kilometers from land. They likely hunted together in groups. Their main food was small fish, about 12 to 20 centimeters long and weighing 40 to 50 grams. Sometimes, they ate fish as big as half their own body. Scientists think they mainly ate Atlantic menhaden and capelin, based on remains found on Funk Island and other clues. Other possible food included lumpsuckers, sculpins, cod, sand lance, and crustaceans. Baby great auks probably ate plankton and sometimes food brought up by their parents.

Descriptions of how the great auk bred are not always accurate. They likely started forming pairs in early to mid-May. They probably stayed with the same partner for life, though some scientists think they might have had other mates, like the razorbill. Once paired, they nested on cliff bases in large groups. They showed off by bobbing their heads and showing their white eye patches, beak marks, and yellow mouths. These groups were very crowded, with one great auk nesting for every square meter of land. The groups were very social. When other birds lived nearby, great auks were dominant because they were larger.

Female great auks laid one egg each year between late May and early June. If the first egg was lost, they might lay another. If food was scarce, they did not breed. The egg was placed on bare ground up to 100 meters from shore. It was oval and long, averaging 12.4 centimeters in length and 7.6 centimeters across. The egg was light yellow or pale orange with black, brown, or gray spots. These spots may have helped parents find their egg in the large colony. Both parents took turns sitting on the egg for 39 to 44 days until it hatched, usually in June, though eggs could be found as late as August.

After hatching, the parents took turns feeding their chick. The chick had gray feathers. It could leave the nest and swim after two to three weeks, around mid-July. Parents cared for their young even after they could fly. Adults were seen swimming with their young on their backs. Great auks reached sexual maturity at four to seven years old.

Relationship with humans

The great auk was a food source for Neanderthals more than 100,000 years ago. Scientists found well-cleaned bones near their campfires. Images of the great auk were carved into the walls of El Pendo Cave in Spain and Paglicci in Italy over 35,000 years ago. Cave paintings of the bird, about 20,000 years old, were found in France's Grotte Cosquer.

Native Americans used the great auk as a food source during winter and as a cultural symbol. Images of the bird were found on bone necklaces. A person buried in Port au Choix, Newfoundland, around 2000 BC, was surrounded by more than 200 great auk beaks, which may have been part of a suit made from their skins. Over half of the bird bones found in graves at this site were from the great auk, showing its importance to the Maritime Archaic people. The extinct Beothuks of Newfoundland made pudding from the bird’s eggs. The Dorset Eskimos also hunted the great auk. The Saqqaq in Greenland overhunted the species, reducing its range in some areas.

Later, European sailors used the great auk as a navigational beacon because seeing the birds meant the Grand Banks of Newfoundland were nearby.

The great auk likely had a population of millions at its peak. It was hunted for food, eggs, and its down feathers from at least the 8th century. Earlier, people in Late Stone Age Scandinavia, Eastern North America, and Labrador hunted the bird, though it was rare there. Early explorers, including Jacques Cartier, used great auks for food and fishing bait. Some sailors herded hundreds of birds onto ships, where they were killed. Reports of this method are debated by some historians. Great auk eggs were valuable because they were larger than murre eggs and had large yolks. Sailors also brought rats to islands, which preyed on great auk nests.

The Little Ice Age may have reduced the great auk’s population by exposing more nesting islands to polar bears. However, human hunting for down feathers was the main cause of its extinction. By the mid-16th century, most nesting colonies in the European Atlantic were destroyed for their feathers, which were used to make pillows. In 1553, the great auk received its first official protection. In 1794, Great Britain banned killing the bird for its feathers. In St. John’s, people who broke a 1775 law banning hunting the bird for feathers or eggs were publicly flogged, though fishing bait hunting was still allowed. In North America, eider down was preferred until eiders were nearly extinct in the 1770s. Then, collectors turned to the great auk as hunting for food, bait, and oil declined.

The great auk disappeared from Funk Island by 1800. In 1794, a sailor named Aaron Thomas described how the birds were hunted:

“If you come for their feathers, you do not kill them. You pluck the best feathers and leave the bird to die. This is not kind, but it is common. You also burn them alive to cook their bodies. You put a bird in a kettle, light a fire under it, and the fire is made of the birds themselves. Their oily bodies catch fire quickly.”

As the great auk became rare, its specimens and eggs were collected by wealthy Europeans. Collectors took only eggs without embryos, often leaving those with embryos behind.

In July 1840, the last great auk seen in Britain was caught and killed on St. Kilda, Scotland. Three men from the island caught a single bird, tied it up, and kept it alive for three days. When a storm hit, they believed the bird caused it and killed it by beating it with a stick.

The last great auk colony lived on Geirfuglasker, a volcanic rock off Iceland. The island was hard to reach, but in 1830, it sank after a volcanic eruption. The birds moved to Eldey, a nearby island. In 1835, nearly 50 birds were found there. Museums collected birds for display. In 1844, the last pair of great auks, along with an egg, was killed at the request of a merchant.

Jón Brandsson and Sigurður Ísleifsson, who killed the last birds, described the event:

“The rocks were covered with guillemots and great auks. The birds walked slowly. I crept up and caught one near the edge of a cliff. I took it by the neck and strangled it.”

A claim of a live great auk in 1852 was accepted by the International Union for Conservation of Nature.

People continued to report seeing the bird for decades after its extinction. The last reported sighting was in 1927 in the Lofotens. Some sightings were hoaxes or mistakes, such as identifying penguins that had been released near Norway.

Scientists are discussing the possibility of reviving the great auk using DNA from preserved specimens. This idea is controversial.

Today, 78 great auk skins remain, mostly in museums, along with about 75 eggs and 24 complete skeletons. Most skins are from summer plumage, and only two are from young birds. No hatchling specimens exist. Each egg and skin has a unique number. Thousands of bones were collected, but few complete skeletons remain. Natural mummies of the great auk were found on Funk Island, including the eyes