I'm not sure about this one... Overall darker brown tones lead me towards Thayer's Gull, however the primaries look incredibly pale and frosty, even for being the underside. Bill on this bird is very petite, which leads me to Iceland gull. The secondaries on a Thayer's Gull should be slightly darker (undersides) than on the undersides of the primaries. The secondaries look nearly as pale as the primaries from the underside, suggesting Iceland. Any thoughts?