Bird of the Month - Blue-winged Teal
By Andy McCormick
Scientific name: Spatula discors
Weight 13 oz (380 g)
AOU Alpha Code BWTE
A bird of the prairie potholes region, the Blue-winged Teal breeds east of the Cascades but can also be found west of Cascades in migration in May, and again in October.
CRESCENT ON FACE AND BLUE ON THE WING
The male Blue-winged Teal has a dramatic white crescent curving down across its face. While in flight a silvery blue patch on the leading edge of the wing and a green speculum on the secondaries marking a contrast visible in flight. The female is much grayer and has a dark line through the eye. There is a remnant of the male’s white crescent in the form of a white mark melding into white on the throat of the female. Both sexes show a large amount of white on the underwing.
WARM WEATHER FRIEND
Like a good snowbird the Blue-winged Teal prefers warm weather and has adapted to migrate north later in spring and south earlier in fall than other ducks. It has one of the shortest breeding seasons among ducks. The nest is a shallow depression lined with grass lined and some down pulled from the parent’s own body (Bent). Usually 9-13 eggs are deposited. Incubation takes about three weeks and the young leave the nest within a day after hatching. They forage on their own and must be quick learners as the parents begin their southward migration before the young can fly. This migration pattern implies that the migration route is instinctive and not learned (Rowher, et al).
Blue-winged Teal migrate in flocks in the fall usually stopping at staging ponds on the way until they molt their flight feathers. As with other ducks, they molt all their flight feathers at the same time and cannot fly until the new feathers grow in.
THE NEW GENUS SPATULA
The genus Spatula of which the Blue-winged Teal is a member was officially resurrected in 2009. The genus Spatula, from the Latin for spoon, was first proposed in 1822 by German zoologist Friedrich Boie (Wikipedia). In taxonomy circles there was a long-held suspicion that the Blue-winged Teal and three other North American ducks, Cinnamon Teal (S. cyanpotera), Northern Shoveler (S. clypeata), and Garganey (S. guerguedula) did not belong in the genus Anas, and now they so not. Worldwide there are 10 species of ducks in the genus Spatula.
OUR ULTIMATE PRAIRIE DUCK
The Blue-winged Teal has adapted to breed in shallow wetlands in the United States and Canada. These areas are subject to annual and seasonal changes and population changes can occur annually. For example, several dry years in the late 1980s led to a 40% drop in population by 1990. However, the following wetter years created more pothole wetlands and the Blue-winged Teal responded in good numbers (Rowher).
Temporary wetlands are more difficult to protect than permanent wetlands, but Ducks Unlimited and National Audubon have advocated for protection of the pothole wetlands breeding areas for ducks. The Blue-winged Teal is actively hunted but at lower rates than other ducks because of its early fall migration. However, Texas and Louisiana have established special September “teal seasons” for hunting, resulting in more juveniles than adults being harvested (Rowher, et al).
The relentless conversion of prairies to agriculture in the United States and Canada has reduced suitable prairie habitat by 50 to 80% in some states and provinces. As early as 1923 Arthur Cleveland Bent bemoaned the loss of 50% of suitable habitat for prairie pothole ducks due to settlement of the North American middle west. In response to this loss of habitat the U.S. Department of Agriculture Conservation Reserve Program has worked with farmers to take 1.8 million acres out of agricultural production and this program has increased the amount of prairie habitat available for waterfowl.
Most Blue-winged Teal spend the winter in Mexico, Central America, and northern South America where pesticides are widely used, creating problems for many wintering birds. Better management of waterfowl requires greater cooperation with these countries. Despite these problems the Blue-winged Teal maintains a stable population and remains one of the most populous ducks in their range. You can see Blue-winged Teal in their face-down foraging style at the Macaulay Library.
References available upon request from firstname.lastname@example.org.