It is alway fun to encounter birds that make you study. With that in mind, here are a few more images of the weird gull.Here is the gull in the middle of the flock with an adult Herring Gull. When the Herring Gull was standing in front of the weird gull. It was taller. You could see the a good portion of the mantle and all of the head.
A little different view of the gull
I tried to get a flight shot that might tell us more. A jogger came along I got my camera ready but it is a point and shot. This is what it got. It isn't much but maybe it will help a little.