- 21.3–23.2 in
- 34.6–37.4 in
- 25.4–57.8 oz
- About the same size as a Mallard; slightly larger than a Gadwall.
- Canard noir (French)
- Ánade sombrio americano (Spanish)
- As soon as their down feathers dry, newly hatched ducklings are able to leave the nest, a depression on the ground lined with plant materials. They follow their mother to rearing areas with a lot of invertebrates to eat and plenty of vegetation for cover.
- Normally found in eastern North America, American Black Ducks occasionally show up on the West Coast, Europe, and even Asia. Some of these birds may be escaped pets, but others are known to be wild ducks: for instance, one female banded in New Brunswick, Canada, turned up later in France.
- Pleistocene fossils of American Black Ducks, at least 11,000 years old, have been unearthed in Florida and Georgia.
- The oldest American Black Duck on record was 26 years, 5 months old.
American Black Ducks breed mostly in freshwater wetlands throughout northeastern North America, including beaver ponds, brooks lined by speckled alder, shallow lakes with reeds and sedges, bogs in boreal forests, and wooded swamps. They may also nest in saltmarshes. They mostly spend the winter in saltwater wetlands, but also in beaver ponds, flooded timber, agricultural fields, and riverine habitats. They often take refuge from hunting and other disturbances by moving to fresh and brackish impoundments on conservation land.
American Black Ducks eat mostly plant matter, with insects added during the breeding season. Plant foods include seeds, roots, tubers, stems and leaves of plants growing in moist soil and underwater. In the breeding season adults and ducklings eat a diet high in animal foods, including aquatic insects (larvae of mayflies, caddisflies, dragonflies, flies and midges, and beetles), crustaceans, mollusks, and sometimes fish. They forage individually or with their mates in the nesting season, and either alone or in small groups during the rest of the year. In shallow water they forage like typical “dabbling ducks” by submerging their heads, or tipping up to reach underwater food. In deeper water they may dive more than 12 feet deep for plant tubers and other food items. On migration they eat seeds, foliage, and tubers of aquatic plants, agricultural grains, seeds and fruits of wild terrestrial plants, invertebrates, and sometimes fish and amphibians. Wintering birds eat mostly plant parts in freshwater habitats, adding foods such as mussels, zooplankton, and small fish in marine habitats.
- Clutch Size
- 6–14 eggs
- Number of Broods
- 1 broods
- Egg Length
- 2.2–2.5 in
- Egg Width
- 1.6–1.8 in
- Incubation Period
- 23–33 days
- Nestling Period
- 1 days
- Egg Description
- White, cream-colored, or pale greenish buff.
- Condition at Hatching
- Well developed and covered with down.
The female builds the nest on her own, digging with her feet and bill in leaf litter or soil to form a basin 7–8 inches across and 1.5 inches deep. While laying eggs, she adds plant material gathered within reach of the nest, including grass, twigs, leaves, stems, and conifer needles. By the fourth or fifth egg she starts adding down feathers plucked from her own body, until the clutch is fully covered at the beginning of incubation.
The female selects a well-concealed site, often on the ground, on wooded or grassy islands, uplands, marshes, cultivated croplands, or cropland borders. She may choose a site in a shrubby area, a brush pile, a hay bale, a patch of grass, or a rock crevice. Nests are sometimes in crotches, hollows, or cavities of large trees.
American Black Ducks are slow, heavy fliers but excellent swimmers, diving to avoid predators and sometimes to find food. Mates are monogamous within each breeding season, and the pairs may stay together in subsequent years. They court and form strong pair bonds in the fall and winter before migrating to breeding grounds. Nesting starts in February in the southern part of their range, but often not until late May in the northern part. The female incubates the eggs while the male defends the territory. Pairs nest near each other fairly peacefully unless one male or pair intrudes; then the territorial male threatens, chases, and fights the intruders. Halfway through incubation, the male becomes less attentive and eventually abandons the nest. The ducklings hatch all within a few hours, and once they are dry the female leads the brood to rearing areas with a lot of invertebrates and plant cover. In early September, after molting, the adult and fledgling ducks join up near breeding areas and begin to migrate south.
American Black Ducks are common, although the North American Breeding Bird Survey has recorded an overall decline in numbers since 1966. (The decline has been less apparent in the last decade.) Long-term winter surveys suggest populations declined by 63 percent between the 1950s and 1990s. Farming, logging, and urbanization in this species’ breeding and wintering habitats, both inland and on the coast, may have contributed to the fall in numbers. Duck hunters intensively exploited American Black Ducks for decades, shooting an estimated 800,000 per year in the 1960s and 1970s. In 1982 the Humane Society of the U.S. pursued a lawsuit that led to stringent hunting restrictions the following year, namely a 30-day season with a one-bird limit per day. Annual harvest in the 1990s was estimated at 166,000 in the U.S., and today records indicate that figure is about 115,000 per year. American Black Ducks are warier than many other duck species, such as Mallards, and thus less tolerant of disturbance. Mallards may have even contributed to the decline in black ducks, since Mallards thrive under urban conditions and may oust their shyer cousins from the habitat (as well as altering local populations by hybridizing with them). Like other aquatic animals, American Black Ducks are sensitive to pollution and runoff that degrade water quality. In the mid-twentieth century the pesticide DDT contributed to eggshell thinning. American Black Ducks also are vulnerable to lead poisoning when they eat spent lead shot while foraging in wetlands.
- Longcore, J. R., D. G. McAuley, G. R. Hepp, and J. M. Rhymer. 2000. American Black Duck (Anas rubripes). In The Birds of North America, No. 481 (A. Poole and F. Gill, eds.). The Birds of North America Online, Ithaca, New York.
- Raftovich, R.V., K.A. Wilkins, S.S. Williams, H.L. Spriggs, and K.D. Richkus. 2011. Migratory bird hunting activity and harvest during the 2009 and 2010 hunting seasons [PDF]. U.S. Fish and Wildlife Service, Laurel, MD.
- Sauer, J.R., J.E. Hines, J.E. Fallon, K.L. Pardieck, D.J. Ziolkowski Jr., and W.A. Link. 2011. The North American Breeding Bird Survey, Results and Analysis 1966–2010. Version 12.07.2011. USGS Patuxent Wildlife Research Center, Laurel, MD.
- U.S. Fish and Wildlife Service. 2012. Harvest Information Program.
- USGS Patuxent Wildlife Research Center. 2011. Longevity records of North American Birds.
Resident or short-distance migrant. Individuals that breed in northwestern Ontario and Quebec migrate the longest distances, 700–800 miles. Individuals in other populations may stay in one place all year or move short distances to avoid freezing water. American Black Ducks migrate at night in small flocks of 12–30, though flocks of several thousand may take off from staging areas in the fall when cold fronts arrive.
Find This Bird
Look for American Black Ducks in both fresh and saltwater in eastern North America, where they will look like female Mallards except with an olive-yellow bill and overall darker, higher-contrast plumage. They prefer protected bodies of water such as saltmarshes and ponds, and frequently mix with other species of ducks, especially Mallards. Among flocks of Mallards, look for a darker, colder-toned duck of similar size; in flight, the white underwings of American Black Ducks form a brighter, more contrasting flash than on a flying Mallard. Because these two species frequently hybridize in eastern North America, be aware that you may see individuals with intermediate characters, such as a dark body and a partially green head.