The great auk, Pinguinus impennis, was a species of flightless seabird native to the North Atlantic, becoming extinct by 1844 due to over-hunting.
The great auk was also known as garefowl (Old Norse: geirfugl, "spear bird"). The name "penguin" was also first applied to these birds before the discovery of similar-appearing species in the Southern Hemisphere in the mid-1500s. The word is possibly based upon the Welsh pen gwyn, referring to the white eye patch on its head.
Largest of the Alcidae family, the great auk was approximately 30 inches tall and weighed up to 11 pounds. Overall color pattern was similar to penguins and the orca, with black plumage on its back, and white feathers on breast and stomach. It is assumed that its movements were similar to the penguin; it waddled on land and used its stubby wings to propel itself in water. Their beaks were large and grooved.
The great auk inhabited the rocky coastlines of Newfoundland, Greenland, Iceland, and western Europe. Shell middens excavated in Florida revealed auk remains, indicating that these birds did a seasonal migration south during the winter months. It has been recently estimated that the overall population of the great auk never exceeded 400,000 at any point in history, possibly due to scarcity of food near shallow water; lack of suitable breeding grounds, natural predators, and the effects of the Little Ice Age.
Based on recovered remains on Funk Island, Canada, the great auk generally ate small fish such as menhadden.
What is known through the habits and records kept by hunting parties was that the great auk could only breed on low-lying rocky coasts with easy access to the water. They bred in colonies, laying a single egg on the bare ground about 4 inches long  which hatched in June.
The great auk was extensively hunted by man; the birds were food, fuel, and provided down for warmth in the northern climates. Early trans-Atlantic crossings were sometimes interrupted by stops at breeding grounds so ship's crews could collect auks en-masse for fresh food and later consumption. Never trully abundant (recent estimates put the auk's numbers at no greater than 400,000), the population was reduced to a handful by 1800.
By 1844, with the auk reduced to a few birds of Iceland, author Robert Silverberg in the 1960s identified science as the main culprit for the species' final demise. According to him, museum curators discovered that the species was about to go extinct, and no specimens were available for display. Collectors began to pay handsome prices to anyone to bring home complete birds or skins; eggs would fetch slightly less. On June 3, 1844, the last two auks were killed on the island of Eldey, off Iceland and their single egg taken.
Today, some 80 great auk mounted specimens from the last phase of the extinction, in addition to skeletons and eggs, are in museums worldwide.
- Silverberg, Robert. The auk, the dodo, and the oryx: Vanished and vanishing creatures; T.Y. Crowell Company, New York (1967)
- Cornish, Jim. The Great Auk: An Extinct Species; (2003) 
- Fuller, Errol. The Great Auk: The Extinction of the Original Penguin; Bunker Hill Publishing, Charlestown, Massachusetts (2003) 
- Jordan, Richard H. & Olson, Storrs L. "First Record of the Great Auk (Pinguinus impennis) from Labrador," article in Auk, January, 1982, pp. 167–168. 
- Weigel, Penelope Hermes. "Great Auk Remains from a Florida Shell Midden," article in Auk, April, 1958 pp. 215–216.