Blue-winged teal

The first formal description of the blue-winged teal was by the Swedish naturalist Carl Linnaeus in 1766 in the twelfth edition of his Systema Naturae. He coined the binomial name Anas discors. A molecular phylogentic study comparing mitochondrial DNA sequences published in 2009 found that the genus Anas, as then defined, was non-monophyletic. The genus was subsequently split into four monophyletic genera with ten species including the blue-winged teal moved into the resurrected genus Spatula. This genus had been originally proposed by the German zoologist Friedrich Boie in 1822. The name Spatula is the Latin for a "spoon" or "spatula". The specific epithet discors is the Latin for "different" or "at variance". ==Description==

The blue-winged teal is long, with a wingspan of , and a weight of . The adult male has a greyish blue head with a white facial crescent, a light brown body with a white patch near the rear and a black tail. The adult female is mottled brown, and has a whitish area at base of bill. Both sexes have sky-blue wing coverts, a green speculum, and yellow legs. They have two molts per year and a third molt in their first year. The call of the male is a short whistle; the female's call is a soft quack. ==Distribution==

The range is all of North America except western and northern Alaska, northern Yukon Territory, northern Northwest Territories and the northeastern area of Canada. Blue-winged teal are rare in the desert southwest, and the west coast. The breeding habitat of the blue-winged teal is marshes and ponds. The breeding range extends from east-central Alaska and southern Mackenzie District east to southern Quebec and southwestern Newfoundland. In the contiguous United States it breeds from northeast California east to central Louisiana, central Tennessee, and the Atlantic Coast. The blue-winged teal winters from southern California to western and southern Texas, the Gulf Coast to the Atlantic Coast, the Caribbean, and south to Central and South America. It is often seen wintering as far south as Brazil and central Chile. ==Habitat==

Blue-winged teal inhabit shoreline more often than open water and prefer calm water or sluggish currents to fast water. They inhabit inland marshes, lakes, ponds, pools, and shallow streams with dense emergent vegetation. The blue-winged teal is primarily found in the northern prairies and parklands. It is the most abundant duck in the mixed-grass prairies of the Dakotas and the prairie provinces of Canada. The blue-winged teal is also found in wetlands of boreal forest associations, shortgrass prairies, tallgrass prairies, and deciduous woodlands. This duck commonly inhabits wetland communities dominated by bulrush (Scirpus spp.), cattail (Typha spp.), pondweed (Potamogeton spp.), sedges (Carex spp.), widgeongrass (Ruppia maritima), and other emergent and aquatic vegetation. During molting, it often remains among extensive beds of bulrushes and cattails. The blue-winged teal favors areas dominated by bluegrass (Poa spp.) for nesting. Hayfields and plant communities of buckbrush (Ceonothus cuneatus) and sedges are also important as nest sites. ==Behavior==

These birds feed by dabbling in shallow water at the edge of marshes or open water. The nest is a shallow depression on the ground lined with grass and down, usually surrounded by vegetation. Blue-winged teal generally lay 10 to 12 eggs. Delayed nesting and renesting efforts have substantially smaller clutches, averaging five to six eggs. Clutch size can also vary with the age of the hen. Yearlings tend to lay smaller clutches. Blue-winged teal ducklings can walk to water within 12 hours after hatching but do not fledge until 6 to 7 weeks. Food habits Blue-winged teal are surface feeders and prefer to feed on mud flats, in fields, or in shallow water where there is floating and shallowly submerged vegetation plus abundant small aquatic animal life. They mostly eat vegetative matter consisting of seeds or stems and leaves of sedge, grass, pondweed, smartweed (Polygonum spp.), duckweed (Lemna spp.), Widgeongrass, and muskgrass (Chara spp.). The seeds of plants that grow on mud flats, such as nutgrass (Cyperus spp.), smartweed, millet (Panicum spp.), and Rice Cut-grass (Leersia oryzoides), are avidly consumed by this duck. One-fourth of the food consumed by blue-winged teal is animal matter such as mollusks, crustaceans, and insects. ==Predators==

Common predators of blue-winged teal include humans, snakes, snapping turtles (Chleydra serpentina), dogs, cats, muskellunge (Esox masquinongy), American crows (Corvus brachyrhynchos), magpies (Pica spp.), ground squirrels, coyotes (Canis latrans), red foxes (Vulpes fulva), gray foxes (Urocyon cinereoargenteus), raccoons (Procyon lotor), long-tailed weasels (Mustela frenata), American minks (Mustela vison), striped skunks (Mephitis mephitis), spotted skunks (Spilogale putorius), and American badgers (Taxidea taxus). During one study, about half of the nest failures of blue-winged teal were caused by mammals. Striped and Spotted Skunks were responsible for two-thirds of these losses. All nest losses caused by birds were attributed to either crows or magpies. ==References==