Wednesday, March 2, 2011

I.D. Tip: Lessons from a Red-winged Blackbird

[Red-winged Blackbird, Nummy Island, NJ, Feb 23, 2011. Click to enarge.]

Good friend Tony Leukering is working up an article and needed some Red-winged Blackbird photos, which set me to re-examining this one of a stretching male from Stone Harbor last week. There's a lot going on, the sort of stuff that gives us the chance to practice the adage, "Know thy common birds."

Most birders would recognize this bird as a male Red-winged Blackbird, but is it an adult or immature (second year, SY, or after second year, ASY, in bander lingo)? And where, exactly, is the red (and yellow) wing patch? Answer to the latter is on the lesser and median coverts, beneath which (or to the right of in this pic) lie the black greater covers and beneath, still farther right, are the stiff flight feathers, the primaries on the outside and secondaries inside.

On the outstretched wing we can count that this Red-winged, like all icterids, has 9 primaries, and that the outermost one (P9) is short. Specifically, it is shorter than P6, a useful in-hand mark to separate Red-winged Blackbird from western cousin Tri-colored. Tri-coloreds, by the way, don't move around much and haven't been recorded east of Nevada, so we almost certainly will never need to deal with one in the east unless someone sticks it in their glove box and brings it here. So there's no need to try to pry the occasional Red-winged Blackbird with pale yellow (almost white) on the coverts into the Tri-colored hole.

And note, as you probably have on other Red-wingeds, that all that red and nearly all the yellow can be hidden under the scapulars, or shoulder feathers, of a perched Red-winged. They often hide their colors when at feeders, to avoid confrontation with other males.

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