Greater scaup is fairly shallow and has an abundance of food sources and cover. The female lays six to nine olive-buff-colored eggs, which she incubates for 24–28 days. A larger clutch could indicate brood parasitism by other greater scaups or even ducks of other species. Newly hatched chicks are covered with down and are soon able to walk, swim, and feed themselves; however, they are not able to fly until 40–45 days after hatching. The vulnerable small chicks follow their mother, who protects them from predators. The greater scaup dive to obtain food, which they eat on the surface. They mainly eat
Greater scaup Isles, western Norway, the southern tip of Sweden, the coast from Brittany to Poland, including all of Denmark, the Alps, the eastern Adriatic Sea, the northern and western Black sea and the southwestern Caspian Sea. In North America, the greater scaup summers in Newfoundland and Labrador, Ungava Bay, Hudson Bay, Lake Winnipeg, northern Yukon, northern Manitoba, and northern Saskatchewan. It winters along the coasts of North America from northern British Columbia south to the Baja Peninsula and from Nova Scotia and New Brunswick south to Florida, as well as the shores of the Great Lakes and the Gulf of Mexico.