Green-winged Teal

The American teal (Anas carolinensis) or green-winged teal is a common and widespread duck that breeds in the northern areas of North America except on the Aleutian Islands. It was considered conspecific with the Eurasian teal (A. crecca) for some time, but has since been split into its own species. The American Ornithological Society continues to debate this determination; however, nearly all other authorities consider it distinct based on behavioral, morphological, and molecular evidence. The scientific name is from Latin Anas, "duck" and carolinensis, "of Carolina". This dabbling duck is strongly migratory and winters far south of its breeding range. It is highly gregarious outside of the breeding season and will form large flocks. In flight, the fast, twisting flocks resemble waders. Taxonomy The green-winged teal was formally described in 1789 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae. He placed it with the other ducks, geese and swans in the genus Anas and coined the binomial name Anas carolinensis. Gmelin based his description on the "American teal" that had been described in 1785 by John Latham in his A General Synopsis of Birds and in the same year by Thomas Pennant in his Arctic Zoology . The genus name Anas is Latin for "duck". The specific epithet carolinensis means "of Carolina". The species is monotypic: no subspecies are recognised. Some authorities treat the green-winged teal as a subspecies of the Eurasian teal (Anas crecca). Description This is the smallest North American dabbling duck. The breeding male has grey flanks and back, with a yellow rear end and a white-edged green speculum, obvious in flight or at rest. It has a chestnut head with a green eye patch. It is distinguished from drake common teals (the Eurasian relative of this bird) by a vertical white stripe on side of breast, the lack of both a horizontal white scapular stripe and the lack of thin buff lines on its head.