Compare Lesser Scaup, Greater Scaup, Tufted Duck & Ring-necked Duck
These four ducks have a similar black and white plumage and i have outlined the differences below.As can be seen on the right of this page, the Greater Scaup has a much more rounded head then the Lesser Scaup. Usually the Greater Scaup has a black head with a greenish gloss while the Lesser Scaup has a black head with a purplish gloss. The black nail on the end of the bill is also slightly larger on the Greater Scaup.
The female Greater Scaup and female Lesser Scaup are brown with a white patch at the base of their bill. The male Greater Scaup in eclipse and male Lesser Scaup in eclipse have a much duller and brownish plumage.
The male Tufted Duck and Ring-necked Duck differ from the Scaup by having a black back or upperparts.
The male Tufted Duck has a distinctive tuft at the back of its black head which has a purplish & greenish gloss. The male Ring-necked Duck has an angular black head with purplish sheen and has a white band around the base of the bill.
The female Tufted Duck is dark brown with a small tuft at the back of the head and white at the base of the bill. The male Tufted Duck in eclipse is more similar to the female with a brownish plumage.
The female Ring-necked Duck is dark brown with whitish chin & throat and brown eyes with white eye-ring but like the male has an angular-shaped head. The male Ring-necked Duck in eclipse has a brownish plumage, dark-brown head, yellow eyes, but lacks the females eye-ring.
Links:
Greater Scaup page
Lesser Scaup page
Tufted Duck page
Ring-necked Duck page