Species, Age and Sex Identification of Ducks Using Wing Plumage

Greater Scaup

GIF-Usual patterns of flecking on scaup middle coverts

Wing Character	Male		Female
Wing Character	Adult	Immature	Immature	Adult
Scapulars	Heavily vermiculated; appear more white than dark	Lightly vermiculated and/or flecked with white; appear more dark than white
Scapulars	Heavily vermiculated; appear more white than dark	After molt: Similar to adult male	After molt: No obvious change
Tertials	Black, some flecked with white near tips, tips pointed and often drooping	Black, usually without flecking; tips pointed, usually frayed and faded	Dark brown, without flecking; tips pointed, usually frayed and faded	Black to very dark brown; without white flecking
Greater tertial coverts	Black, without flecking to very lightly flecked with white near tips; broadly rounded	Black to dark brown, without flecking; narrow toward tips	Dark brown, without flecking; narrow toward tips	Black to very dark brown without white flecking; broadly rounded
Middle and lesser coverts	Black; all are well vermiculated with white	Black to dark brown with large white flecks to small vermiculations recessed 1/8" from coverts' edge; often ragged and notched at tip	Black to dark brown, without white flecks; often ragged and notched at tip	Black to dark brown, plain or with very small white flecks concentrated near coverts' edge; broadly rounded at tip