Anas discors
These ducks are called blue-winged teal because both sexes have blue spots on their forewings. They also have large white patches on the front of the wing, best visible when in flight. Males are smaller than females. Males have a large white crescent on their face, between the eye and the bill, and a white patch on their rear. Females lack the crescent and white patch, they have dull gray-brown coloration.
Wingspans range from 56 to 62 cm, and total lengths are typically 36 to 41 cm. Adults weigh 280 to 499 g.
During the summer months, blue-winged teal can be found throughout North America, from southeastern Alaska to the Atlantic coast. They are found in as far south as the Gulf Coast of Texas and Louisiana. In the winter months they migrate to the southern parts of the U.S. and into Central and South America.
Freshwater habitats for blue-winged teal include shallow ponds and wetlands. During breeding season, blue-winged teal remain near the water's edge in ponds and wetlands, preferring to breed in areas of calm, sluggish water.
Blue-winged teal have a single mate during the breeding season, but they usually change mates between breeding seasons. Pairs are formed on wintering grounds and during spring migration.
Males perform courtship displays to attract females. Usually, courtship begins in flight, when males call and pursue females. A typical on-water display would be: a male swims in front of a female and with his body at an angle to her and his head pointing away. The female accepts a male by stretching her head outward. Then her head is lowered and her bill is pointed toward the male. At the end they both bob their heads up and down.
Blue-winged teal nest from late April through early May. They breed in wetland areas within grasslands, shallow marshes, sloughs, flooded ditches, and temporary ponds. Females lay 6 to 14 eggs, which take 21 to 40 days to hatch. Young reach the fledgling stage at about 24 days and are independent after 40 days.
Females are in charge of nest maintenance and rearing the young, males do not help out. Females make a nest by digging a bowl-shaped depression and pulling in dried grass. She lays one egg per day, up to around 10 or more eggs. When the eggs hatch the female preens her hatchlings until they are dry and clean. She then leads her ducklings to a nearby wetland and does not return to the nest. The young remain with their mother until they are ready to fly, about 40 days post-hatching.
Most blue-winged teal ducklings do not survive through their first few years. They get parasites and diseases as young birds or do not survive their first migration attempt. Botulism (Clostridium botulinum) and avian cholera (Pasteurella multocida), both bacterial diseases, kill blue-winged teals when they are found in the water where they live. Blue-winged teal that do survive to adulthood can live up to 17 years.
Blue-winged teal are very social, except during the breeding season when males and females move off into nesting areas. They migrate between wintering and breeding ranges each year and are active during the day. Blue-winged teal can walk well on land and in shallow water. They often rest and preen on logs and rocks that are slightly above water. They can gain flight directly from land or water. The only time a blue-wing teal will dive in the water is if threatened by a predator or when trying to escape from other ducks.
Blue-winged teal establish small territories around nests during the breeding season.
Male blue-winged teal make a set of sounds to attract females, including a high-pitched whistle "peew" and low-pitched nasal "paay."
Females use loud quacks during the breeding season to communicate with their mates and with their young.
Blue-winged teal eat a variety of aquatic invertebrates and vegetation. Invertebrate prey include insects, crustaceans, snails, and small clams. They also eat seeds. When females are breeding they require a diet higher in protein, so they eat more invertebrates and seeds.
Long-tailed weasels often consume blue-wing teal eggs. Females are preyed on by raptors when they are on their nests. In prairies, these ducks are captured by red foxes. Females and ducklings are cryptically colored to avoid detection by prey.
Other predators include: peregrine falcons, mink, raccons, bald eagles, great horned owls, red-tailed hawks, coyotes, striped skunks, American badgers, American crows, black-billed magpies, and Franklin's ground squirrels.
Blue-winged teal impact populations of aquatic invertebrates and vegetation by eating them. They are a source of prey for many predators. Blue-winged teal often flock with other species of dabbling ducks.
Blue-winged teal don't negatively impact humans directly. However, many ducks species, including blue-winged teal, can carry and transmit avian influenza.
Blue-winged teal are game birds. (Rohwer, et al., 2002)
Blue-winged teal, although not rare, are protected under the Migratory Bird Act. Teal are hunted throughout much of their range, although hunting is generally regulated. Blue-winged teal populations have been harmed by pesticides such as dieldrin and by eating or being trapped in plastic trash. They are also hit by cars and can become entangled in power lines, fences, and other human structures. Blue-winged teal populations, along with the populations of many other duck species, have declined because of human destruction of wetlands.
Tanya Dewey (editor), Animal Diversity Web.
Monica Mingo (author), Radford University, Karen Powers (editor, instructor), Radford University.
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