On Friday afternoon, I went down to Ashbridges Bay and found five Iceland Gulls on the ice by the parking lot, and one more on the ice by the marina to the south. I haven't seen a Glaucous Gull there yet this year, but that doesn't mean they haven't been around. To me, the Glaucous looks like an albino Great Black-backed Gull--big, boxy, broad-shouldered, with a flat head, a huge bill, and a mean expression. Also, the folded wingtips are usually pure white, whereas the Iceland Gulls I've been seeing at Ashbridges have wingtips with light grey markings on them.
On Friday, there was also a single Thayer's Gull on the ice by the parking lot, and a female Ruddy Duck in the water by the marina.