Black-bellied whistling ducks are easily recognized. Males and females look similar with red bills, pink feet, white wing patches, and black bellies. The head is brownish-gray with a white eye-ring.
Black-bellied whistling ducks are gregarious. They can often be found perching in trees. While they prefer to nest in natural tree cavities, they will readily use nest boxes and have been reported to nest on the ground as well.
The behavior of black-bellied whistling ducks is similar to fulvous whistling ducks. They prefer the excellent feeding opportunities offered by agricultural lands in close proximity to water, rice culture, and shallow wetlands with exposed mud flats. Black-bellied whistling ducks prefer to feed at night but have been observed feeding at all hours of the day.
Since 1968, black-bellied whistling ducks frequently have been found in central and south Florida in late summer and early fall, sometimes mixed in flocks of fulvous whistling ducks. In recent years, these ducks have become year-round residents in all of peninsular Florida. As these birds can adapt to almost any habitat in rural and urban areas, their population is expected to grow. Banding and telemetry data have shown many of these birds now migrate to north Florida, Georgia, and the Carolinas to breed during the summer. In fact, black-bellied whistling ducks are steadily increasing their range with recent confirmed breeding pairs in Wisconsin and Delaware.