Gull ID?

Taken Thanksgiving weekend at Chincoteague NWR. Looks like a Herring gull to me (maybe 3rd year?), but I never feel confident with gulls......

It looks fine for Herring Gull. I see no sign of brown, very little dark on the bill, and the white wing spots look clean and well formed so I assume it's an adult.

Thanks. I'm curious, what would the brown have suggested?

Brown feathers in the mantle and wing coverts of large, white-headed gulls are generally an indication of immaturity. If you go to the Herring Gull account on BirdFellow (link below) and look at ID photo #16, you can see blackish-brown coloration on the wing coverts while the black in the primary feathers looks more like an adult. This bird is probably about one year shy of being a full adult.

http://www.birdfellow.com/birds/herr...atus#/idPhotos