I've been seeing lots of Thayer's and Lesser Black-backeds lately and so it was nice to get on this Glaucous Gull on Sunday:
|Glaucous Gull (3rd cycle). Lake County, IL. 08 Dec 2013.|
Other highlights for the day included this adult Thayer's:
And this 3rd cycle type and 2nd cycle type Lesser Black-backed, respectively:
But perhaps most intriguing were these "white-winged" adult Herrings:
Unlike the Northeastern United States and Newfoundland/Labrador, American Herring Gulls on the Great Lakes and the Western United States typically show a limited amount of white on the outer primaries. On average, the so-called "Great Lakes" birds show a single mirror (on P10) and smaller white apicals, and tend to average smaller body proportions. But it's open season in the winter, with a mix of all sort of Herring Gulls.
Seeing birds with this much white in the wingtips in my area (Illinois) may invite confusion with Thayer's. But note the staring pale-yellow eye, and the yellow-orange orbital ring. Thayer's shows a pinkish orbital.