In alternate plumage adult males have a white crown and forehead and a broad, dark green patch surrounding the eye and nape. The bill is blue-gray with a black tip. The rest of the neck, face and upper back is buffy white with heavy black speckling. The breast and flanks are reddish brown with a bright white underbelly. Upperwing-coverts are white so that there is a large white patch when wings are extended. In alternate plumage adult females have a brownish black crown, streaked with creamy white. The bill is grayish with a black tip. The rest of the head and neck is white with heavy streaking and the back is grayish brown with light barring. Flanks are reddish brown and the belly is white. The white wing patch is poorly defined in the female. In basic plumage adult males resemble females but may have slightly brighter sides and flanks.
The American wigeon is most likely to be confused with the Eurasian wigeon, which is seen only rarely in North America. In alternate plumage, the adult male Eurasian wigeon is most easily distinguished from the adult male American wigeon by its red head and gray back and sides. Females and juveniles are very similar but can be distinguished by the axillars, which are finely speckled with dark gray in the Eurasian wigeon, but pure white in the American wigeon. (Mowbray, 1999)
The American wigeon has very large winter and breeding ranges that spread north to the tips of Alaska and Canada, and south through Mexico to the northern parts of South America. Winter distribution is concentrated in the lower 48 states and all of Mexico, excluding high elevation Rocky Mountain and Appalachian areas. Breeding takes place mostly in western Canada but is spread throughout northwestern North America. (Mowbray, 1999)
In the winter, the wigeon is found most often in lacustrine and intertidal areas where the emergence of plants material is abundant. It inhabits freshwater marshes, rivers, lakes, estuaries, saltwater bays, and agricultural lands.
During the breeding season it prefers areas with vegetation cover near lakes or marshy sloughs. Mixed grass and short grass prairies are preferred for breeding.
Pair formation can begin with the arrival on wintering grounds. Breeding is not controlled strictly by photoperiod, but is also infleunced by habitat quality and food availability on the wintering grounds. Presumably the female selects the nest site, which is well concealed on dry ground and away from the water. Nests are typically found in areas of tall grasses and brush cover and in fairly close proximity to a food supply. They are constructed primarily of grasses and weed stems and lined with down. Incubation begins at the completion of the clutch and usually continues for an average of 25 days. The female spends almost 90% of the day on the nest; when the paired male is not accompanying the female in feeding, he spends the majority of his time on the water. He remains with the female only until the second week of incubation.
Young are precocial at hatching. They are able to leave the nest with the female less than 24 hours after hatching. They feed eagerly by dabbling and off the surface. Fledgling age is estimated at between 37 and 48 days. This period varies depending on factors such as habitat and climatic conditions, age and condition of female, and time of hatching. (Ehrlich, et al., 1988; Mowbray, 1999)
Females provide care of the offspring once they hatch. (Ehrlich et al., 1988)
Reports of longevity vary considerably between sources. There have been recorded accounts of American wigeons up to 21 years of age. The average lifespan for a female is 1.7 years and the average lifespan for a male is 2.3 years.(Mowbray, 1999)
Wigeons spend most of their time during the day swimming and feeding, and in general are most active on the water. They do not form large congregations except during migration or where there is a large source of food. They will join small flocks of gadwalls, mallards, American coots and various diving ducks occasionally during fall migration.
Wigeons are territorial during the breeding season. Individual territories tend to be spaced out, usually a single pair to a pond. (Mowbray, 1999)
Shallow, freshwater wetlands, marshes, mudflats, slow moving rivers, and ponds are all potential areas for foraging for wigeons. These are areas where the abundance of emergent plant life and insects is the greatest. They will feed on a variety of aquatic insects such as damselflies and caddisflies, as well as terrestrial insects such as beetles. This type of food comprises a small part of their diet however. The largest food source is stems and leafy parts of aquatic plants, grasses, and agricultural plants. They particularly prefer muskgrasses and bushy pondweed. Differences between juvenile and adult food preferences have been noted.
These birds are better adapted morphologically and physiologically for grazing on aquatic and terrestrial plants than most other North American birds. They use the strength in the tip of their bill to pluck vegetation and also filter feed with the lamellae on the upper mandible. They are opportunistic and aggressive feeders, often foraging in open water on materials brought to the surface by diving ducks and coots.
Common foods eaten include: stems and leafy parts of aquatic plants, leafy parts of upland grasses, leafy parts and seeds of agricultural plants, aquatic insects, beetles, mollusks and crustaceans.
(Mowbray, 1999; Knapton and Pauls, 1994)
If a female senses a predator while incubating she will rise silently and fly far away from the nest or toward the water to distract the predator. Females also perform a distraction display where they will feign injury, flap their wings over water, vocalize, and possibly become aggressive toward an intruder.(Mowbray, 1999)
Being a grazing duck, it tends to congregate in hay fields and sometimes golf courses, but no substantial negative effects are known.
Wigeons are hunted by people and make up a small percentage of the U.S. duck sport harvest. There is no significant commercial take of this species.
Human activity can potentially affect the American wigeon in many ways because it is a game bird and also a migratory species. Despite hunting pressures and habitat degredation, populations seem to be stable. However, in recent years there has been a slight decline in numbers because of habitat loss due to land use and change in climate in the Canadian prairie parklands. Restoration programs are working where habitat potential is the greatest and these efforts are forseen to improve the situation. General management objectives apply to the wigeon and they are protected under the Migratory Bird Treaty Act. (Mowbray, 1999; Bethke and Nudd, 1995)
Kari Kirschbaum (), Animal Diversity Web.
Sadie Taylor (author), University of Arizona, Jay Taylor (editor), University of Arizona.
Bethke, R., T. Nudds. 1995. Effects of climatic change and land use on duck abundance in Canadian prairie parklands. Ecological Applications, 5: 588-600.
Ehrlich, P., D. Dobkin, D. Wheye. 1988. "Birds of Stanford: American Wigeon" (On-line). Accessed 23 September 2002 at http://www.stanfordalumni.org/birdsite/text/species/American_Wigeon.html.
Knapton, R., K. Pauls. 1994. Fall food habits of American Wigeon at Long Point, Lake Erie, Ontario. Journal of Great Lakes Research, 20: 271-276.
Mowbray, T. 1999. American Wigeon, No. 401. Pp. 1-32 in A Poole, F Gill, eds. The Birds of North America. Washington, DC: The Academy of Natural Sciences, Philadelphia, PA, and The American Ornithologists' Union.