Hybrid Gulls?

I took this picture last February at Swan Lake. Currently, my best guess is that this is a hybrid gull, possibly Glaucous-winged x American Herring Gull, or a somewhat odd (to my eyes) Thayer’s Gull. I eliminate pure Glaucous-winged Gull because of the very dark on the primaries. I eliminate pure Herring Gull due to … Read more