Species, Age and Sex Identification of Ducks Using Wing Plumage

Harlequin Duck

Wing Character	Male		Female
	Adult	Immature	Immature	Adult
Tertials	Distal three are mostly white on their outerwebs and their tips are not frayed	Distal three are dark brown; paler near their shafts; usually frayed at their tips; sometimes an adult-type replacement permits sex identification		Dark gray; blunt and their tips are not frayed
Secondaries	Very dark iridescent blue	Dark brown; often appear ragged		Black, shading to gray; tips smoothly rounded and not frayed
Greater coverts	Two or three have large white spots; all are dark blue	Dark brown; often slightly faded; may appear ragged		Black, shading to dark gray; tips smoothly rounded and not frayed
Middle and lesser coverts	Most are dark blue; usually three have white spots	Dark brown; tips are usually ragged		Black-tipped; shading to dark gray on bases of coverts