Blue-winged Teal

The blue-winged teal is one of the smaller dabbling ducks, about 40 cm long, found in North America. It breeds in marshes and ponds from southern Alaska to Nova Scotia and south to northern Texas, and winters along the coasts, in the Caribbean and in Central and South America, sometimes as far south as Brazil and central Chile. Males have a greyish blue head with a white facial crescent, while females are mottled brown. Both sexes have sky-blue wing coverts and yellow legs. It feeds by dabbling in shallow water, taking mostly plants, and sometimes molluscs and aquatic insects.

About the blue-winged teal

The blue-winged teal is a small dabbling duck in the family Anatidae, the same family as swans, geese and the mallard. It breeds across much of North America, from southern Alaska to Nova Scotia and south to northern Texas, and migrates in winter to the southern United States, the Caribbean, and Central and South America.

Its scientific name is Spatula discors. Carl Linnaeus first described it in 1766 as Anas discors, and for a long time it sat in the same genus as the mallard. A 2009 study of mitochondrial DNA showed that the old genus Anas was not a natural group, so the blue-winged teal was moved into the revived genus Spatula, Latin for "spoon." The species name discors is Latin for "different" or "at variance."

This is one of the smaller dabbling ducks. An adult is about 40 cm (16 in) long with a wingspan near 58 cm (23 in), and a typical weight is about 370 g (13 oz). Animal Diversity Web gives a wider spread of 36–41 cm (14–16 in) in length, 56–62 cm (22–24 in) across the wings, and 280–499 g (9.9–17.6 oz) in weight. Females are the larger sex.

The drake is easy to pick out in breeding plumage. He has a greyish-blue head with a bold white crescent between the eye and the bill, a light brown body, a white patch near the rear and a black tail. The hen is mottled brown with a whitish spot at the base of the bill. Both sexes share the feature that gives the bird its name: sky-blue patches on the forewing, along with a green speculum and yellow legs. The blue shows best in flight, together with large white patches on the front of the wing. Blue-winged teal molt twice a year, with an extra molt in their first year. The male's call is a short whistle, and the female gives a soft quack.

Behavior and diet

Blue-winged teal are dabblers. They feed at the surface in shallow water at the edges of marshes, on mud flats and in flooded fields, rather than diving. Most of the diet is plant matter: seeds, stems and leaves of sedges, grasses, pondweed, smartweed, duckweed, widgeongrass and muskgrass. Seeds of mud-flat plants such as nutgrass, millet and rice cut-grass are taken eagerly. About one-quarter of what they eat is animal food, including mollusks, crustaceans and insects.

They are highly social, living in flocks for most of the year and splitting into pairs only in the breeding season. The birds are diurnal, walk well on land, and often rest and preen on logs, rocks and muskrat houses just above the water. They can take off straight from land or water. A blue-winged teal dives only to escape a predator.

Migration timing sets this species apart. Blue-winged teal are generally the first ducks to head south in fall and the last to return north in spring. Adult males leave the breeding grounds well before females and young birds, so most flocks seen after mid-September are hens and juveniles. Large numbers arrive on wintering grounds in Florida, Louisiana and Texas in September. Some birds cross long stretches of open ocean during migration, and the species turns up as a vagrant in Europe, where it has become an annual visitor to Britain and Ireland.

Pairs usually form on the wintering grounds or during spring migration, and pairs stay together for one season. Courtship often starts in flight, with several males chasing a single female. Blue-winged teal are among the last dabbling ducks to nest, usually between mid-April and mid-May. The female scrapes a shallow bowl on dry, grassy ground, lines it with grass and down, and lays one egg a day, typically 10 to 12 in total. Incubation lasts 21 to 27 days. During this time the drake leaves and moves to dense cover to molt, losing the ability to fly for three to four weeks.

The hen raises the young alone. The ducklings can walk to water within 12 hours of hatching, and they fledge at around six to seven weeks. Birds are ready to breed after their first winter.

Range and habitat

In summer, blue-winged teal occur across most of North America except western and northern Alaska, the far north of Canada's territories and northeastern Canada. Breeding runs from east-central Alaska east to southern Quebec and southwestern Newfoundland, and in the lower 48 states from northeastern California east to central Louisiana, central Tennessee and the Atlantic coast. Some populations nest along the Atlantic coast from New Brunswick to Pea Island, North Carolina. The species is rare in the desert Southwest and along the West Coast.

The heart of the breeding range is the northern prairies and parklands. It is the most abundant duck in the mixed-grass prairies of the Dakotas and Canada's prairie provinces. It also uses wetlands in boreal forest, shortgrass and tallgrass prairie, and deciduous woodland.

These ducks prefer shorelines to open water and calm or slow-moving water to fast currents. Typical sites are inland marshes, lakes, ponds and shallow streams thick with bulrushes, cattails, pondweed and sedges. On the coast, they breed in salt-marsh meadows next to ponds or creeks. Nests sit on dry ground in bluegrass meadows, hayfields and sedge meadows, usually within several hundred yards of water, though some have been found 1.6 km (1 mi) away.

Winter range runs from southern California across Texas and the Gulf Coast to the Atlantic coast, through the Caribbean and into Central and South America. Wintering birds use shallow freshwater, brackish and saltwater marshes, and the species is often seen as far south as Brazil and central Chile.

Conservation status

The blue-winged teal is listed as Least Concern on the IUCN Red List, based on a 2021 assessment by BirdLife International. NatureServe ranks it G5, meaning globally secure.

The main pressures fall on eggs and young. A long list of animals prey on blue-winged teal or their nests, including humans, snakes, snapping turtles, crows, magpies, coyotes, foxes, raccoons, minks, badgers and skunks. In one study, mammals caused about half of all nest failures, and striped and spotted skunks were behind two-thirds of those losses.

Disease and migration also take a toll. Botulism and avian cholera, both bacterial diseases picked up by ingestion, hit populations hard, and migration is a major cause of death for young teal.