As it has been proposed that this gull which was originally identified as a Viking Gull is a Thayer’s Gull I have posted a selection of photos for you to scroll through. The gull was seen feeding in the shade behind a large building while the sun shone from a clear blue sky. Thus auto white balance in the camera produced some off coloured cold photos at firsts, but in this post I have set the white balance to shade.
The discussion takes place at www.gull-research.org.
For comparison have a look at this nice photo by Peter Adriaens and this flying individual by Chris Gibbins.
Here are some more photos from California by Jeff Poklen and Chris Gibbins for comparison, whereas there are these photos from this side of the Atlantic at Birding Frontiers, the Irish Rare Birds Committee web, the Irish Bird Images and here.
Identification criteria in general are discussed here and at Surfbirds.
Please comment on the ID of this gull...
|Note the dark brown tail with some white marks at the base of the retrices|