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Quite the posture!
Here’s an angle on a species that many of us seen frequently, but possibly not often like this. The features that grab my eye, include the white belly, the orange throat, and the white wing stripe.
“What? White wing stripe? What is that?”
Yes, indeedy! This month’s quiz photo was selected in order to discuss another feature that is often not seen or, if seen, ignored or not fully understood by many birders. Though there is a variety of different wing stripes in birds, the one that I wish to discuss here is the one created by the bases of the secondaries and at least the inner primaries that are contrastingly paler than both the distal portions of those secondaries and primaries and the wing linings (comprised of the various under-wing coverts). Our quiz bird shows a fairly bold wing stripe on each wing that extends into the outer primaries, though it’s not all that obvious way out there. The distinctness of the wing stripe is dependent both on the brightness of the bases of the relevant flight feathers and on the darkness of the tips of those flight feathers and of the wing linings.
In most species that show this sort of wing stripe, it is typically less noticeable or not visible from above, due, in part, to the relative lengths of the greater coverts on the upper- and under-sides of the wings; the upper greater coverts are often longer than the respective under-side feathers. Another determinant of how visible the wing stripe is from above is the width of those pale bases, with the wider the bases, the more visible the wing stripe.
While this feature is often thought of as a feature of passerines groups, it shows up in a number of non-passerine groups, particularly shorebirds, with the ne plus ultra example being Willet. However, it is a useful feature to look for on cranes passing overhead, as Sandhill Crane sports it, while neither Whooping nor Common do.
But, our quiz bird is obviously – hopefully, anyway -- a passerine, and at least a few members of a number of passerine families exhibit wing stripes: nuthatches (though they have a distinct twist on the feature), creepers (all one ABA-Area species), thrushes, wagtails, and finches, to name most of them. As a cautionary note, Red-faced Warbler does not sport this type of wing stripe, as that species’ white patch on the under side of the wing is on the coverts; it is not composed of pale bases to the flight feathers.
Please submit the correct Common or English name exactly as it appears in the ABA Checklist.