The black-bellied whistling duck (Dendrocygna autumnalis) is a distinctive waterfowl. Unlike many ducks, it possesses long legs and an upright posture, with a goose-like appearance. Its bright pink bill and legs, along with a contrasting black belly and chestnut back, make it easily recognizable. This highly social bird often forms large flocks and can be quite vocal, emitting a soft, high-pitched whistling call.
Geographic Distribution
The black-bellied whistling duck is widely distributed across the American continent, from the southern United States through Central and South America. In the United States, populations are found in states such as Texas, Florida, Louisiana, and Arizona, with their abundance greatest along the U.S. Gulf Coast. Their year-round presence extends through Mexico and Central America. The species also ranges into South America, including Venezuela, Colombia, Ecuador, Peru, Brazil, and Argentina.
Two subspecies are recognized: Dendrocygna autumnalis fulgens and Dendrocygna autumnalis autumnalis. The northern subspecies, D. a. fulgens, is larger with a brown breast and upper back, inhabiting areas from the southern United States down through coastal Mexico and Central America. The southern subspecies, D. a. autumnalis, is smaller with a gray breast and upper back, found from Panama south into Argentina. These subspecies intergrade in Panama, creating a continuous distribution across their range.
Migration Patterns
While many black-bellied whistling duck populations in tropical and subtropical regions are resident year-round, northern populations exhibit seasonal migratory behaviors. Ducks in the United States typically depart their breeding areas between August and October, migrating south for the winter. They often move into Mexico or Central America, seeking warmer climates and consistent food sources.
These migratory birds return to their northern breeding grounds in late March or April. Migration patterns can vary depending on local environmental conditions, such as food availability and water levels. Although historically considered non-migratory, significant migratory movements are now observed in the northern and southernmost parts of their range.
Preferred Habitats
Black-bellied whistling ducks show a strong preference for freshwater wetlands, including marshes, ponds, and shallow lakes. They also inhabit slow-moving rivers and flooded agricultural fields, such as rice paddies, where they find abundant food. These ducks favor areas with dense emergent or floating vegetation, which provides cover from predators and suitable nesting sites.
They are known for their arboreal tendencies, often perching in trees near water, a behavior that earned them the nickname “tree ducks.” Nests are commonly built in tree cavities, though they will also use artificial nest boxes. Their diet consists primarily of plant material, including seeds of aquatic plants and cultivated grains like rice and corn.