The mallard is the most common duck in the United States, with the greatest abundance between the Appalachian and Rocky mountains. Mallard populations have benefited greatly from the Conservation Reserve Program (CRP) and other grassland restoration efforts in the northern prairies of the United States, where populations have increased 100 percent above the long-term average.The mallard is one of the most recognized of all ducks and is the ancestor of several domestic breeds. Its wide range has given rise to several distinct populations. The male mallard’s white neck-ring separates the green head from the chestnut-brown chest, contrasts with the gray sides, brownish back, black rump and black upper- and under-tail coverts. The speculum is violet-blue bordered by black and white, and the outer tail feathers are white. The bill is yellow to yellowish-green and the legs and feet are coral-red. Male utters a soft, rasping “kreep.” The female mallard is a mottled brownish color and has a violet speculum bordered by black and white. The crown of the head is dark brown with a dark brown stripe running through the eye. The remainder of the head is lighter brown than the upper body. The bill is orange splotched with brown, and the legs and feet are orange. Mallards have one of the most extensive breeding ranges of any duck in North America, extending across the northern third of the United States and up to the Bering Sea. The highest mallard densities occur in the Prairie Pothole Region of Saskatchewan, Alberta, Manitoba and North Dakota, with nests placed in upland habitat near wetlands on the ground, or in tree holes or nest boxes. Female mallards lay an average of 9 eggs.
Mallards migrate along numerous corridors, but the greatest concentrations move from Manitoba and Saskatchewan through the Midwestern United States to the Mississippi Alluvial Valley. Mallards winter throughout the United States, with the highest densities typically recorded during winter surveys along the Mississippi Flyway from Cape Girardeau, Mo., to the Gulf of Mexico. Among the dabbling ducks, mallards are one of the latest fall migrants. They also have the most extended migration period, which lasts from late summer to early winter. Mallards are found in a variety of habitats, including dry agricultural fields, shallow marshes and oak-dominated forested wetlands.