This afternoon at Potash Bay, there were a zillion (give or take a few - I didn't use a clicker) Ring-Billed Gulls and one that wasn't. At first I thought it was a Greater Black-Backed Gull, but it was just about the same size as two Ring-Bills that shared its little patch of ice. Also, as I studied the gull some more, it was clear that the back was dark gray, not true black.
(The three gulls were very far away, which means the gulls with the mystery bird could have been Herring Gulls - in which case the dark-backed gull was larger than I thought. I kept going back and forth visually with nearer gulls that I knew were Ring-Billeds and ended up relatively sure the two lighter gulls on the ice with the dark one were Ring-Billeds.)
I decided to try a few pictures by holding my camera up to the end of the scope. The two are not meant to go together, and I ended up using a makeshift "sleeve" of my mitten. Out of 31 attempts, I got only one that is even recognizable as a gull. I've posted this awful photo at http://www.flickr.com/photos/86960264@N05/
I watched the unusual gull for about twenty-five minutes, hoping it might fly closer. The gull preened for a long time and then seemed to be settling down for a nap - so I headed home to see if iPhoto could work any magic with any of the photos. (It couldn't.)