Lesser Scaup, Aythya affinis

Lesser Scaups can be found in a variety of freshwater habitats, including lakes, ponds, marshes, and rivers. They breed in the northern regions of North America, including Alaska and Canada, and migrate to wintering grounds in the southern United States, Mexico, and parts of Central America. Some populations also winter along the coastal regions of the United States.

Lesser Scaups are diving ducks. They feed on a wide range of prey, including insects, mollusks, crustaceans, and small fish. Scaups are adept divers and can submerge themselves to considerable depths in search of food. They use their serrated bills to grasp and consume their prey underwater.

Lesser Scaups engage in courtship displays, which involve head-bobbing, tail-raising, and vocalizations.

During the breeding season, Lesser Scaups nest in shallow wetlands with dense emergent vegetation. They construct their nests on floating mats of vegetation or in areas with floating debris. The female builds the nest using plant material such as cattails, bulrushes, and sedges. The nests are typically well concealed and lined with down feathers for insulation.

Females lay 7-11 olive-buff colored eggs. Incubation, which lasts around 23-29 days, and is primarily undertaken by the female. The male leaves shortly after mating and does not contribute to incubation or care of the young. Once the eggs hatch, the female leads the ducklings to the water within a day or two. The young are precocial and capable of swimming and foraging for food immediately. The female provides guidance and protection to the ducklings until they are independent.

Lesser Scaup ducklings typically fledge within 45-50 days after hatching depending on food availability and other environmental factors. During the winter, Lesser Scaups undertake long-distance migrations, moving from their northern breeding grounds to more southerly wintering areas. They often gather in large flocks on lakes, reservoirs, and coastal habitats during this time.

Lesser Scaups are known for their rapid wingbeats and swift takeoffs when in flight.

They have been observed to practice a behavior called “drinking.” They extend their necks forward and immerse their bills in the water, creating a drinking motion. The purpose of this behavior is not well understood but is believed to aid in maintaining feather condition and possibly in thermoregulation.