Iceland Gull adult

Bird shifted position on the berm, with under primaries more difficult to discern. Better view of small thin bill with small gonys; bill was mostly greenish-yellow (especially basally) rather than the more yellowish of Herrings and Ring-billeds, and had only minimal distal dark near the red gonydeal spot. Iris was dark, an important characteristic of most Thayer's, seen less frequently in Kumlien's (though there are exceptions for both). Adult Herring almost always has a bright yellow iris.