They Came by the Hundreds

What a spectacle it was.  Hundreds of white birds flying in circles above the swake; swooping low, grazing the water's surface only to climb again and repeat the dance.  Out came the binoculars along with the hope of identifying the new guests.  But it was impossible to focus on one and follow it long enough to gather any information on markings.  They flew so swiftly, round and round in huge magnificent circles as if they were on some invisible gymnastic ribbons being manoeuvred from the sky.  Trying to watch them through binoculars made me dizzy so I had to rely on my own two eyes.

We watched them at different times of day in varying light and weather always wondering what they were.  They looked gull-like and they seemed to be feeding on insects right above the water line.  Finally I couldn't stand just watching, I needed to try the zoom lens and see what the results were.  Well, the sun was high and I took the photo from the deck hoping for the best.  After playing with the photo a bit, here is the result.  I think we were watching a colony of hundreds of Franklin's Gulls Franklin's Gulls.  Can anyone out there zoom in on the photo and verify which birds came to visit by the hundreds?