Lake County, Illinois. Sunday, 19 March 2017.
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The contrasting gray slivers on the outer webs of p8-p9 are hardly noticeably with brighter light. See next image.
No doubt this bird wouldn't get a second look in nominate glaucoides' winter range.
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| At this angle, the lighting projects a Kumlien's left wing and a Thayer's right wing. Perhaps more important than any other factor when identifying adults in this complex, is lighting! |
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| The open bill gives this individual a very large-headed appearance. If it was summer in Anchorage, it would be identified as a Cook Inlet Gull. |
