Species, Age and Sex Identification of Ducks Using Wing Plumage

Redhead

Immature greater coverts are narrower, squared, often frayed to a point over the tertials with an indistinct pale tip over the secondaries. During the hunting season, immature birds occasionally replace both their immature tertials and greater tertial coverts with adult-type feathers. For a given sex, these new feathers are indistinguishable from those of adults but differ markedly from other immature greater and middle coverts which are retained. With practice, redheads can be aged primarily by the appearance of their tertial coverts. Several combinations are possible: 1) immature-type tertial coverts always indicate an immature bird but sex is best determined from other coverts; 2) adult male or adult female-type coverts similar to the surrounding coverts indicate an adult of that sex; 3) adult male or adult female-type tertial coverts that differ from the surrounding immature-type coverts indicate the sex of some immature birds.

Wing Character	Male		Female
	Adult	Immature	Immature	Adult
Tertials	Usually taper to a rounded point; some well vermiculated	Usually frayed to a sharp, ragged pint; without flecking or vermiculation		Usually taper to a rounded point, without flecking or vermiculation
		After molt: Similar to adult male	After molt: Similar to adult female
Greater tertial coverts	Broad, smoothly rounded and flecked or vermiculated	Appear narrow, and usually have ragged pointed tips		Broad, smoothly rounded without flecking or vermiculation
		After molt: Similar to adult male	After molt: Similar to adult female
Middle and lesser coverts	Broadly rounded; may vary from entirely vermiculated to lightly flecked	Often narrow somewhat toward tips; tips often appear notched		Broadly rounded and entirely plain to faintly flecked near their tips
		Flecking may vary from conspicuous to barely discernable	Entirely plain

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