The Labrador duck (Camptorhynchus labradorius) is an extinct North American bird. The Labrador Duck has the dubious distinction of being the first species among endemic North American birds to go extinct. It was already a rare duck before European settlers arrived and became extinct shortly after. As a result of its rarity, there is not an abundance of information on the Labrador Duck but there is some such as its habitat, characteristics, dietary habits, and reasons behind extinction. According to the Naturalis Museum there are 54 specimens of the Labrador Duck preserved in museum collections worldwide.However, according to Chilton, there are actually 55 specimen of this rare duck around the world. 
The Labrador duck is considered a sea duck. A basic difference in the shape of the process of metacarpel I divides the sea ducks into two groups: (1) Bucephala and the mergansers, and (2) the eiders, scoters, Histrionicus and Clangula. The Camptorhynchus falls into the second group. Furthermore, the position of the nutrient foramen of the tarsometatarsus also separates the two groups of sea ducks. In the first group foramen lies lateral to the long axis of the lateral groove of the hypotarsus; in the second the foramen lies on or medial to the axis of that groove. Once again the Camptorhynchus resembles the eiders, scoters, and their relatives in this respect.
The Labrador duck was also known as the pied duck and skunk duck, the former being a vernacular name that it shared with the surf scoter and the common goldeneye (and even the American oystercatcher), a fact that has led to difficulties in interpreting old records of these species. Both names refer to the male's striking white/black piebald coloration. Yet another common name was sand shoal duck, referring to its habit of feeding in shallow water. The closest evolutionary relatives of the Labrador duck are apparently the scoters (Melanitta).
The female plumage was gray. Although weakly patterned, the pattern was scoter like. The male’s plumage was black and white in an eider like pattern, but the wings were entirely white except for the primaries. The trachea of the male was scoter like. There was an expansion of the tracheal tube at the anterior end and two enlargements (as opposed to one enlargement as seen in scoters) near the middle of the tube. The bulla was bony and round, puffing out from the left side. This asymmetrical and osseus bulla was unlike that of scoters; this bulla was similar to eiders’ and the harlequin duck’s bullae. The Labrador Duck is of the most enigmatic of all North American birds. 
The Labrador duck had an oblong head with small, beady eyes. Its bill was almost as long as its head. The body was short and depressed with short, strong feet that were far behind the body. As per the feather, they were small and the tail was short and rounded. One last known fact of the Labrador duck is that it belonged to a monotypic genus. 
The Labrador duck migrated annually, wintering off the coasts of New Jersey and New England—where it favoured southern sandy coasts, bays, and inlets—and breeding in Labrador in the summer. John James Audubon's son reported seeing a nest belonging to the species in Labrador, but it is uncertain where it bred. Some believe that it may have laid its eggs on the islands in the Gulf of Saint Lawrence.This duck used to live on sandy sheltered bay, inlets, harbours, and anywhere that was on the shore of the east coast. The breeding biology of the Labrador Duck is unknown, but it is believed that they breed in Labrador and Northern Quebec.  
The Labrador duck fed on small molluscs, and some fishermen reported catching it on fishing lines baited with mussels. The structure of the bill was highly modified from that of most ducks, having a wide, flattened tip with numerous lamellae inside. In this way it is considered an ecological counterpart of the North Pacific/North Asian Steller's eider. The beak was also particularly soft, and may have been used to probe through sediment for food.
Another, completely unrelated, duck with similar (but even more specialized) bill morphology is the Australian pink-eared duck, which feeds largely on plankton, but also mollusks; the condition in the Labrador duck probably resembled that in the blue duck most in outward appearance. Its peculiar bill suggests it ate shellfish and crustaceans from silt and shallow water. It is possible that the Labrador Duck survived by eating snails.
The Labrador duck used to be offered in the markets of New York and Baltimore . It was the type of meat that easily rotted. Therefore the extinction of this duck due to hunting cannot be a reasonable explanation of its disappearance. The logical explanation discussed assumes that due to a specialized diet, considering the shape of its beak, it resulted in the ducks to be vulnerable to adapt in its environment. The last Labrador duck to be seen was in 1875 in Long Island. That duck is now preserved in the United States National Museum in Washington. Shooting and getting on the winter quarters were doubtlessly proximate variables in the species demolition. Overharvest of birds and eggs on the breeding grounds could have been another reason. It is likely that environment level were affected after the arriving of Europeans that decreased the supply of available nutrition.
It is thought that the Labrador duck was always rare, but between 1850 and 1870, populations waned further. Its extinction is still not fully explained. Although hunted for food, this duck was considered to taste bad, would rot quickly and fetched a low price. Consequently, it was not sought much by hunters. However, it is thought that the eggs may have been over-harvested, and it may have been subject to depredations by the feather trade in its breeding area as well. Another possible factor in the bird's extinction was the decline in mussels and other shellfish on which they are believed to have fed in their winter quarters, due to growth of population and industry on the Eastern Seaboard. Although all sea ducks readily feed on shallow-water molluscs, no Western Atlantic bird species seems to have been as dependent on such food as the Labrador duck.Another theory that was said to lead to their extinction was that there was a huge increase of human influence on the coastal ecosystems in North America, causing the birds to flee their niches and find another habitat. These ducks were the only birds whose range was limited to the American coast of the North Atlantic, so changing niches was a difficult task. The Labrador Duck went extinct in the late 19th century. The duck soon disappeared after the first wave of European settlement. The bird’s specialized ecological niche is believed to have played a major role in its extinction.
- ^ BirdLife International (2012). "Camptorhynchus labradorius". IUCN Red List of Threatened Species. Version 2013.2. International Union for Conservation of Nature. Retrieved 26 November 2013.
- ^ Chilton, Glen. The Curse of the Labrador Duck: My Obsessive Quest to the Edge of Extinction. New York: Simon & Schuster, 2009. Print.
- ^ Zusi, Richard. "The Appendicular Myology of the Labrador Duck (Camptorhynchus labradorius)". JSTOR. The Condor. Retrieved 24 October 2014.
- ^ Livezey, Bradley C. (1995). "Phylogeny and Evolutionary Ecology of Modern Seaducks (Anatidae: Mergini)". Condor 97 (1): 233–255. doi:10.2307/1368999.
- ^ Johnsgard, Paul. "Handbook of Waterfowl Behavior: Tribe Mergini (Sea Ducks)". Retrieved 24 October 2014.
- ^ "Recently Extinct Animals - Species Info - Labrador Duck." Recently Extinct Animals - Species Info - Labrador Duck. N.p., 4 June 2008. Web. 22 Oct. 2014. <http://www.petermaas.nl/extinct/speciesinfo/labradorduck.htm>.
- ^ Chilton, Glen, and Michael D. Sorenson. "Genetic Identification Of Eggs Purportedly From The Extinct Labrador Duck (Camptorhynchus Labradorius)." Auk (American Ornithologists Union) 124.3 (2007): 962-968. Academic Search Premier. Web. 23 Oct. 2014.
- ^ name=gap>Flannery, Tim (2001). A Gap in Nature. New York: Atlantic Monthly Press. pp. 60–61. ISBN 0871137976.
- ^ a b c Flannery, Tim (2001). A Gap in Nature. New York: Atlantic Monthly Press. pp. 60–61. ISBN 0871137976.
- ^ "Labradoreend." Natuurinformatie. Naturalis Biodiversity Center. Web. 24 Oct. 2014. <http://www.natuurinformatie.nl/nnm.dossiers/natuurdatabase.nl/i001317.html>.
- ^ BirdLife International 2012. Camptorhynchus labradorius. The IUCN Red List of Threatened Species. Version 2014.2. <www.iucnredlist.org>. Downloaded on 23 October 2014.
- ^ Phillips, John C. (1922–1926): A Natural History of Ducks. Boston: Houghton-Mifflin, volume 4, pp. 57–63.
- ^ Amadon, Dean. "Migratory Birds of Relict Distribution: Some Inferences." The Auk 70.4 (1953): 461-69. JSTOR. Web. 22 Oct. 2014. <http://www.jstor.org/stable/10.2307/4081357?ref=no-x-route:956a9a013036c5b67a48060b92a78a49>.
- ^ Wilson, E.O. Biodiversity II: Understanding and Protecting Our Biological Resources. Washington, DC: John Henry Press, 1996. Print. http://books.google.com/books?hl=en&lr=&id=-X5OAgAAQBAJ&oi=fnd&pg=PA139&dq=labrador+duck+extinction&ots=f1QlkA4_cq&sig=k7BgO7drcRl9YZV8DaWFDmmzyz8#v=onepage&q&f=false
- ^ "All About Birds." : Labrador Duck. Cornell University, 2007. Web. 22 Oct. 2014. <http://www.birds.cornell.edu/AllAboutBirds/conservation/extinctions/labrador_duck/document_view>.
- Chilton, Glen (2009): The Curse of the Labrador Duck: My Obsessive Quest to the Edge of Extinction. Simon and Schuster, ISBN 1-43910247-3.
- Cokinos, Christopher (2000): Hope is the Thing with Feathers. New York: Putnam, pp. 281–304. ISBN 1-58542-006-9
- Ducher, William (1894): The Labrador Duck – another specimen, with additional data respecting extant specimens. Auk 11: 4–12. PDF fulltext
- Forbush, Edward Howe (1912): A History of the Game Birds, Wild-Fowl and Shore Birds of Massachusetts and Adjacent States. Boston: Massachusetts State Board of Agriculture, pp. 411–416.
- Fuller, Errol (2001): Extinct Birds, Comstock Publishing, ISBN 0-8014-3954-X, pp. 85–87.
- Madge, Steve & Burn, Hilary (1988): Waterfowl. An identification guide to the ducks, geese and swans of the world. Boston: Houghton Mifflin, pp. 265–266. ISBN 0-395-46727-6