The ubiquitous Mallard (Anas platyrhynchos) is a familiar sight to most of us. Though it prefers shallow ponds and marshes for its habitat, it can turn up on almost any unfrozen body of water in our area at any time of the year.

The drake is easily identified as a Mallard most of the year by its bright iridescent green head, rich brown breast, white neck ring, yellow bill, and pale gray body.

The hen Mallard, though, can be confused with the American Black Duck (Anas rubripes) a declining, but still common bird. These two closely related species are nearly identical in size, structure, and voice, but, with practice, even female Mallards can be readily distinguished from Black Ducks by their plumage. The American Black Duck is found in habitats like the Mallard’s, but tends to be somewhat warier of humans, and so favors more secluded areas. Though outnumbered by Mallards at all times of the year here, Black Ducks become more common relative to the Mallard in migration seasons and in winter, when more northern breeding populations of Black Ducks migrate south.

Many are surprised to learn that in the past the Mallard did not breed in the northeastern United States at all. Our Mallard population consists of the descendants of birds released by hunters and wildlife officials, and of escapes from parks and private waterfowl collections. The resounding success of the Mallard in our area is thought to have affected the native and formerly much more common Black Duck adversely, through competition for habitat and hybridization.

Hybrid Mallard X Black Ducks are seen fairly frequently, and can show almost any combination of features of the two species, an unfortunate complication for the identification guidelines given above. Fortunately, these hybrids are vastly outnumbered by typical-looking birds that can be clearly assigned to one species or the other.