Unfortunately, I could never get a photo of this adult bird coming in or leaving. The distinct pattern of pale gray primaries of the underwing with darker subterminal band and white tips were the tell tell signs on this rare adult Thayer's Gull. I know there must be quite a few adults visiting the area but they are difficult to pick out, much harder than the more numerous immatures. Resting, the small bill, rounded head and dark eye are the features to search for among the light eyed, large billed Herring Gulls.