RANGE:much of Northern Hemisphere
HABITAT:wetlands including lakes, ponds, marshes
DIET: HERBIVOREaquatic plants and seeds
OFFSPRING:9-11 eggs/clutch, on average
LENGTH:18.1 - 22.4 in (46-57 cm)
WEIGHT:17.6 - 44.1 oz (500 - 1250 g)
“Where I live”
Gadwalls live throughout much of the Northern Hemisphere. They spend the summer breeding season on northern prairie grounds, in the northwest United States and southwest Canada. They are commonly seen on lakes and ponds.
Gadwalls migrate for the winter to the southern United States, the Pacific and Atlantic coasts, and south into Mexico and Central America.
Gadwalls can be seen in the Chesapeake Bay region from early fall until early spring, usually in marshes away from the shoreline in mixed flocks with other waterfowl and American Coots.
“How I live there”
Gadwalls are surface feeders, and feed mostly in the shallows on submerged plants growing close to the water’s surface. They eat the leaves and seeds of pondweeds, widgeon grass, water milfoil, algae, smartweeds, bulrush, and spike rush.
“Making my mark”
Up close, the male gadwall has a striking pattern of intricate markings on all its body feathers.
“What eats me”
Eggs and chicks are vulnerable to a number of predators, including gulls, raccoons, ground squirrels, and skunks. Adult gadwalls may be hunted in season.
Gadwalls renew pair bonds each year rather than staying with the same mate perennially. Each pair chooses a nesting site together, and females construct nests on the ground where they are well concealed. Very often, gadwall pairs will choose to nest on an island where they are forced to tolerate the presence of other gadwall nests. Males may attempt to discourage other pairs from nesting nearby, but usually will be unsuccessful and end up tolerating the relative proximity of other nests.
Females lay clutches of 9-11 eggs on average. Soon after females begin incubating eggs, their mates desert them and begin their post-nuptial molt. Incubation lasts 25-27 days. After eggs hatch, females move their broods away from nest sites into deep-water marshes.
Gadwalls are considered a species of least concern by the IUCN, the world’s leading conservation organization, which means that they are relatively stable across their range.
The number of gadwalls wintering on the Chesapeake Bay has rebounded steadily since the 1970s and has increased to record levels. They and other dabbling ducks are benefiting from ongoing efforts to restore aquatic plant acreage in the Bay.
Johnsgard, Paul A. Waterfowl of North America. Bloomington: Indiana University Press, 1975, pp. 197-207.