While birding above the falls on Sunday at Niagara I observed an adult "white-winged" gull in flight. My first thought was a Glaucous Gull because it had immaculate white primaries tips, but it was to small. Once it landed in a group of loafing Herring Gulls, I could see it had the size and proportions of an Iceland Gull ( rounded head, smaller bill, and long primary projection). Ben and I and others in the group watched it closely for a hour. The gull spent most of the time preening and we had excellent close views through the scope. All the field marks indicated an adult "Greenland" Iceland Gull. As the OFO field trip arrived the gull took flight and headed up river towards the control gates and disappeared. The nominate subspecies or "Greenland " Iceland Gull is very rare in Ontario with a specimen record from Ottawa in the Canadian museum of Nature. Ben and I took numerous photos, which are on my blog below. As we are all aware some identifications of gulls can be extremely difficult! Below is a link to Ontario Birds: Recognizable Forms: by Ron Pittaway covering the subspecies of Iceland Gulls in Ontario.
Good birding, Bruce and Ben
Probable Adult "Greenland" Iceland Gull with Herring Gulls.
Below are 5 photos of the probable "Greenland" Iceland Gull showing open wing