Greater Scaup

The Greater Scaup, colloquially known as "bluebill" in North America, is a mid-sized diving duck with a notable presence across the Northern Hemisphere. The drakes, or males, are distinguished by their bright blue bills and yellow eyes, with a dark head that shimmers with a green gloss. Their plumage features a black breast, white belly, and a white stripe along the wing. Females, on the other hand, are predominantly brown with white wing markings and a duller blue bill, accented by white facial features.

Identification Tips

To identify the Greater Scaup, look for the male's rounded head, bright blue bill, and yellow eyes. The female is more subdued in color but shares the white wing markings. In flight, both sexes display a prominent white stripe extending from the wing's speculum to the tip. The Greater Scaup can be distinguished from the similar Lesser Scaup by its more rounded head and more extensive white wing stripe.

Habitat

Greater Scaup breed in the tundra and boreal forests, often on islands within northern lakes or on floating vegetation. They winter in coastal bays, estuaries, and occasionally inland lakes.

Distribution

This species has a circumpolar distribution, breeding in Alaska, northern Canada, Siberia, and northern Europe. In winter, they migrate to the coasts of North America, Europe, and Japan.

Behaviour

Greater Scaup form large flocks, or "rafts," sometimes numbering in the thousands. They are known for their complex courtship rituals, which culminate in monogamous pairings.

Song & Calls

The drake's courtship call is a soft, quick whistle, while the female emits a raspy "arrr-arrr-arrr-arrr-arrr."

Breeding

Breeding begins at two years of age, with nesting typically on islands or floating vegetation near water. Females lay six to nine olive-buff eggs, which hatch in 24 to 28 days. The down-covered ducklings are precocial and follow their mother immediately after hatching.

Diet and Feeding

Greater Scaup dive to feed on aquatic molluscs, plants, and insects. They can dive up to 6 meters deep and stay submerged for about a minute.

Conservation status

Despite facing threats from human development and predation, the Greater Scaup is currently listed as a species of Least Concern on the IUCN Red List.

Similar Species

The Lesser Scaup is the most similar species, but it can be differentiated by its less rounded head and less extensive white wing stripe.