the body plumage, back of the neck and cap are a rich chestnut brown. The face and upper neck are gray, and they sport a thin but distinct white eye-ring. The extensive white in the wings is obvious in flight, less so on the ground; it is formed by the secondary remiges while the primaries are black; the wing-coverts are brown. Males and females look alike; juveniles are similar but have a gray bill and less contrasting belly. The wing bar is unique among whistling ducks. When on the ground, it may be hard to discern the light flanks present in many of these waterfowl. The fulvous whistling duck (D. bicolor) is the only sympatric whistling duck that shows such a whitish flank stripe, and it differs from the black-bellied by having dark wings and a lighter belly rather than the other way around. Juvenile D. autumnalis are quite similar to young of the white-faced whistling duck (D. viduata), which have a darker bill and no white wing patch; even when sitting they never seem to show white along the sides, as their thin white vertical barring on the black flanks is very indistinct. As the name implies, these are noisy birds with a clear whistling waa-chooo call. Distribution and habitat The black-bellied whistling duck is mainly non-migratory, although they are listed on the List of Birds protected by the Migratory Bird Treaty Act (MBTA). At the heart of their range, there is a tendency to travel in flocks over the winter months, though this behavior is not a true long-range migration but rather local dispersal. In the 21st century, small numbers have been observed nesting in the Midwestern U.S., including Ohio, Missouri, Illinois, Indiana, and Wisconsin, as well as the eastern U.S. and Canada. Behavior and ecology The black-bellied whistling duck is a common species that is "quite tame, even in the wild". It is highly gregarious, or social, forming large flocks when not breeding, and is largely resident apart from local movements. It usually nests in hollow trees (in South America many times in palm trees). The habitat is quite shallow freshwater ponds, lakes, and marshes, cultivated land or reservoirs with plentiful vegetation, where this duck feeds mainly at night on seeds and other plant food. Breeding The black-bellied whistling duck is quite unique among ducks in their strong monogamous pair-bond. Its pairs often stay together for many