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American black ducks continue to account for about 5 percent of Pennsylvania's total duck harvest.
The elusive American black duck is particularly prized by hunters.
The American black duck returns each year to the same pond, even if it is still frozen.
It is intermediate in appearance between the female mallard and the American black duck.
American Black Duck populations have been in continuous decline since the 1950s.
American black ducks, mallards and northern pintails are common winter visitors.
While this is not a problem in the plentiful mallard, it might place an additional strain on the American black duck's population.
Each species, from roseate terns to American black ducks, has very different needs for food, water, shelter and space.
Not more than four may be American Black Ducks.
Species singled out for protection in Killcohook include the American black duck.
For example, the American black duck has been often reported hybridising with the mallard, starting a slow decline.
Or take the American black duck.
Effect of restrictive harvest regulations on survival and recovery rates of American black ducks.
American Black Duck and Canada Goose did not make the list.
Blood parasites and hybridisation between American black ducks and mallards.
In the process, the scientists say, they displace native species, including crabs, oysters, shorebirds and the American black duck.
A reconsideration of the American Black Duck with special reference to certain variations.
Waterfowl are primarily American black ducks and bufflehead.
Depletion of lipid, lean, and ash masses in food-restricted American black ducks.
Good numbers of Mallards and American Black Ducks are also still around.
Scientists say mute swans push native species like the American black duck and the canvasback out of their natural habitat.
American Black Duck To view annual indices of population change please click on a geographic area.
We also found evidence of a sexual difference in endogenous nutrient utilization by American black ducks in response to food restriction.
American black duck: Iridescent violet bordered in black and may have a thin white trailing edge.
“A century of hybridization: decreasing genetic distance between American black ducks and mallards.”
However, these statements do not refer to the Dusky/Black Duck (Anas rubripes; syn.
In St. Lawrence River marshes, fatal sporadic and epizootic typhlitis in breeding populations of black ducks, Anas rubripes; blue-winged teal, A. discors; and migrant green-winged teal, A. carolinensis, is attributed to Cyathocotyle bushiensis Khan, 1962.