I was just about to leave when I spotted a really smart juvenile Iceland Gull on the water. It must only just have arrived, as it wasn't there during my first sweep through the gulls. It had dark eyes and a more or less black bill so it's a juvenile. The primaries were completely white, so L. g. glaucoides rather than L. g. kumlieni. Kumlien's Gull can have white primaries without obvious markings apparently, but in the UK it's an Iceland Gull.
This is the 12th Iceland Gull I've seen at Shawell since I started my long term study back in 2012. I have been lucky enough to have found 10 of them myself.