Species, Age and Sex Identification of Ducks Using Wing Plumage


The underwing of all oldsquaws is a uniform patterned dark brown to black. On adult males, the innermost tertials are solid black, and the outer tertials and adjacent secondaries show traces of rust. The remainder of the wing is an unpatterned black. On adult females, the tertials and adjacent secondaries are a dark rufus brown that has a tan edging. Tertial coverts, middle coverts, and most lesser coverts are dark brown to black heavily washed with tan. The upper wing of both sexes of immatures is uniformly dark brown, often with a faint trace of rust on the secondaries and tertials. Immatures can be recognized by the frayed and faded tips of their tertials and tertial coverts.

Wing Character Male Female
Adult Immature Immature Adult
TertialsAcutely pointed, black, most show trace of rustDark gray-brown; usually show trace of rustDark brown with trace of rust; usually tan edging
Greater tertial covertsEntirely blackDark brown, usually frayed and faded at tipsDark brown; tips washed with tan
Greater secondary covertsEntirely blackDark brown; frayed and faded at tipsDark brown; tips washed with tan
Middle and lesser covertsEntirely blackEntirely dark brownDark brown; heavily washed with tan
SecondariesDark rusty brownBrown with traces of rustBrown to rusty brown

JPG-Adult male oldsquaw JPG-Adult female oldsquaw JPG-Immature oldsquaw

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