Species, Age and Sex Identification of Ducks Using Wing Plumage

Surf Scoter

All surf scoter wings are dark and unpatterned on both upper and under surfaces. Only adult males are black. Wings of all other sex-age categories are dark brown. Among these, adult females can be identified by their broadly rounded tertials and greater coverts over both secondaries and tertials. On immature birds, tertials are pointed and usually frayed and faded at their tips, and greater coverts over both secondaries and tertials are quite narrow and have frayed and faded tips.

Wing Character	Male		Female
	Adult	Immature	Immature	Adult
Primaries	Outermost primary similar to and as long as or longer than the adjacent primary
	Outer webs black	Outer webs dark blackish brown
Tertials	Shiny black and bluntly pointed; approximately 20 mm. longer than most secondaries	Dark brown and pointed; may be faded at their tips		Very dark blackish brown; tips bluntly pointed; usually less than 20 mm. longer than most secondaries
Tertial coverts	Shiny black	Dark brown; noticeably narrower than those of adults; often faded at their tips		Very dark blackish brown; smoothly rounded tips
Greater, middle, and lesser coverts	Entirely black; appear smooth	Dark brown; most greater coverts are faded at their tips; they often appear rough		Very dark blackish brown; some are slightly faded at their tips; all appear smooth

Previous Section -- Black scoter
Return to Contents
Next Section -- White-winged scoter