Greater Scaup
A species of Diving ducks, Also known as Bluebill Scientific name : Aythya marila Genus : Diving ducks
Greater Scaup, A species of Diving ducks
Also known as:
Bluebill
Botanical name: Aythya marila
Genus: Diving ducks
Content
Description People often ask General Info
Photo By silversea_starsong , used under CC-BY-NC-4.0 /Cropped and compressed from original
Description
The adult greater scaup is 39–56 cm (15–22 in) long with a 71–84 cm (28–33 in) wingspan and a body mass of 726–1,360 g (1.601–2.998 lb). It has a blue bill and yellow eyes and is 20% heavier and 10% longer than the closely related lesser scaup. The male has a dark head with a green sheen, a black breast, a light back, a black tail, and a white underside. The drake or male greater scaup is larger and has a more rounded head than the female. The drake's belly and flanks are a bright white. Its neck, breast, and tail feathers are a glossy black, while its lower flanks are vermiculated gray. The upper wing has a white stripe starting as the speculum and extending along the flight feathers to the wingtip. Legs and feet of both sexes are gray. The adult female has a brown body and head, with white wing markings similar to those of the male but slightly duller. It has a white band and brown oval shaped patches at the base of the bill, which is a slightly duller shade of blue than the drake's. Juvenile greater scaup look similar to adult females. The greater scaup drake's eclipse plumage looks similar to its breeding plumage, except the pale parts of the plumage are a buffy gray. Distinguishing greater from lesser scaups can be difficult in the field. The head of the greater tends to be more rounded, and the white wing stripe is more extensive.
Size
44 cm (17.5 in)
Colors
Brown
Black
Green
Gray
White
Life Expectancy
13 years
Nest Placement
Ground
Clutch Size
5 - 13 eggs
Incubation Period
1 brood
Number of Broods
23 - 28 days
Feeding Habits
Greater Scaup's diet consists of mollusks, crustaceans, insects, plants, and seeds, with variations such as leopard frogs occasionally. They forage by day or night, diving up to 23 feet, utilizing bill movements in mud for invertebrates, and staying submerged for about a minute. They feed in large, current-facing flocks.
Habitat
Greater Scaup primarily inhabits northern circumpolar regions, favoring marshy tundra and islands in freshwater lakes for breeding. Preferring treeless wetlands, greater Scaup selects areas shielded from wind, with shallow water rich in sustenance, and vegetated with submergent and emergent flora. During migration, greater Scaup utilizes shallow waters of large inland lakes, like the Great Lakes, for rest and foraging. Winters are spent along coastal bays, estuaries, and occasionally inland waters, encompassing parts of the Pacific and Atlantic coasts of North America, European coastal areas, and inland seas in Asia.
Nest Behavior
Greater Scaup females construct nests, lay eggs in dense cover by water, and exhibit parental care with brood rearing.
Nest Characteristics
The nest of greater Scaup is a ground depression near water lined with grass, plant material, and down feathers, forming a saucer shape in dense grass or sedge cover.
Dite type
Aquatic invertebrate eater
People often ask
General Info
Sounds
Call
Recording location: United States
Call
Recording location: United States
Behavior
Greater Scaup's are adept divers, plunging up to 23 feet deep to forage on benthic invertebrates. They are sociable, often forming tight-knit flocks, sometimes in the company of other divers. These monogamous birds select annual mates with elaborate courtship displays, where males vie for females' attention through physical posturing and vocalizations. Post-breeding, males gather in rich feeding sites to molt before migrating, while females show site fidelity, frequently returning to familiar nesting areas.
Distribution Area
The greater scaup has a circumpolar distribution, breeding within the Arctic Circle both in the Old World (the Palearctic) and in North America (the Nearctic). It spends the summer months in Alaska, Siberia, and the northern parts of Europe. It is also found in Asia and is present in the Aleutian Islands year round. The summer habitat is marshy lowland tundra and islands in fresh water lakes. In the fall, greater scaup populations start their migration south for the winter. They winter along the Pacific and Atlantic coasts of North America, the coasts of northwest Europe, the Caspian Sea, the Black Sea, the coast of Japan, Yellow Sea and East China Sea. During the winter months, they are found in coastal bays, estuaries, and sometimes inland lakes, such as the lakes of Central Europe and the Great Lakes. In Europe, the greater scaup breeds in Iceland, the northern coasts of the Scandinavian peninsula, including much of the northern parts of the Baltic Sea, the higher mountains of Scandinavia and the areas close to the Arctic Sea in Russia. These birds spend the winters in the British 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.
Species Status
Greater scaup are rated as a species of least concern by the IUCN Redlist. During aerial population surveys greater and lesser scaup are counted together, because they look almost identical from the air. It was estimated that the greater scaup made up about 11% of the continental scaup population. Since the 1980s, scaup populations have been steadily decreasing. Some of the primary factors contributing to this decline are habitat loss, contaminants, changes in breeding habitat, and a lower female survival rate. The 2010 American scaup population survey was 4.2 million scaup, however, the worldwide greater scaup population survey estimated 1,200,000 to 1,400,000 mature greater scaup. Along with the aerial population surveys, there is a banding program for the greater scaup. Metal leg bands are placed on them, so that if the scaup is killed by a hunter or if it is captured by another banding group, the number on the band can be reported to biologists and wildlife organizations. These banding programs yield valuable data about migration patterns, harvest rates, and survival rates.
Photo By silversea_starsong , used under CC-BY-NC-4.0 /Cropped and compressed from original