A canvasback duck, scientific name Aythya valisineria, is a large duck with distinctive markings that include a light colored back. It is native to North America, living mainly on ponds, wetlands, and lakes, and it migrates on a seasonal basis. It is also known as a diving duck that feeds by diving under the water for food. It breeds during the summer in northern regions of the continent.
Considered a large duck, the adult canvasback is approximately 19 to 22 inches (48 to 56 cm) in length with a wingspan of about 31 to 35 inches (79 to 89 cm) across. It often weighs between 1.9 and 3.5 pounds (0.9 to 1.6 kg) and has a sleek, rounded body shape. It has a relatively large head with a long, smoothly sloped face and bill when viewed from the side.
The male and female canvasback duck have different color patterns. The female's colors are more muted, with brown eyes, a medium brown head and neck plus a light grayish brown back and body. The male has a lot more contrast with red eyes, a bright reddish brown head and neck, a black chest, a white body including the back, and a black rear end. Both sexes of canvasback duck have black bills and dark blue-gray legs and feet.
The canvasback duck is only found in North America, breeding in northern regions and migrating south in the winter. It breeds most often in an area known as the Prairie Pothole Region, which stretches from southern areas of Canada to parts of Montana, the Dakotas, Minnesota, and Iowa in the U.S. Many shallow wetlands, or "potholes," left by glacier movement are located in this area of the northern Great Plains. The ducks migrate south to spend the winter in slightly warmer areas including the Gulf Coast, the Mississippi Delta region, Chesapeake Bay, and the San Francisco Bay.
Preferred habitats of the canvasback duck include marshes, wetlands, ponds and lakes during warm months. It spends the winter on bays, large lakes, and estuaries that are unlikely to freeze over. The canvasback feed primarily by diving under the water surface for food, which usually consists of aquatic plants, invertebrates such as snails and insects, and occasionally small fish. The ducks have a strong preference for wild celery, Vallisneria americana, when it is available, a fact referenced by the species name valisineria.
The male and female canvasback ducks usually select their mates in late winter before returning to the summer breeding grounds. The female lays 5 to 11 eggs in a nest made of grasses and reeds lined with downy feathers. The nest is built anchored to areas of thick vegetation in the marsh. The female incubates the eggs for about 24 days and takes care of the young ducklings when they hatch until they are able to leave the nest.