Dabbling ducks are birds that use their bills to "dabble" for food near the water's surface or shallow waters. Most dabbling ducks in the United States belong to the Anas genus, which includes species such as the mallard, mottled duck, northern and white-cheeked pintails, common and green-winged teals, northern shoveler and garganey. Dabbling ducks have smaller feet than diving duck species, since they do not need the propulsion for swimming under water. However, dabbling ducks are quicker fliers than diving ducks since they do not need a running start on the water for takeoff.
As their names suggest, diving ducks always dive into deep waters in search for food such as fish, crustaceans and vegetation. Diving ducks have larger feet than dabbling ducks, which assist them in swimming quickly under water. The feet of diving ducks are fully webbed. However, a diving duck's feet are near the rear of its body, making it more difficult to fly. When taking off, diving ducks require a running start on the water. Some of the United States' diving ducks are canvasbacks, scaups, ring-necked ducks, pochards, buffleheads and ruddy ducks.
Approximately 42 percent of all American ducks are sea ducks, according to Katherine Mehl of Ducks Unlimited. Sea ducks live in saltwater estuaries and coastal regions. Scoters, eiders, goldeneyes and mergansers make up some of the United States' sea duck populations. Many sea duck breeds are year-round residents of their environments. These ducks usually mature later in life than freshwater species; sea ducks do not breed until they are 2 or 3 years old. Depending on their diet, sea ducks have specialized bills that differ from most freshwater ducks.
Two species of perching ducks live in the United States, the muscovy duck and wood duck. Perching ducks have clawed feet that enable them to climb trees. These ducks eat fish, insects and vegetation. Trees and bodies of water are the main eating sites for perching ducks. Wood ducks usually build nests in branches hanging over a lake or pond, while muscovy ducks develop nests in tree cavities. The muscovy duck is an introduced species in the United States from Mexico and Central America. A male muscovy duck may be identified by the red, warty bumps on its beak.