Iceland Gulls are uncommon but regular white season visitors to parts of New England. Along with Glaucous Gulls, they're referred to as "white-winged" gulls, as all ages have light-colored wings with little to no dark markings.
Iceland Gulls take 4 years to acquire adult plumage, and for their 1st year are a generally evenly patterned off-white to tan color with pink legs and a dark bill (see photo above and gallery below). Adults have a mostly white body, a gray mantle, gray upper wings (with/without limited black at primary tips), and a yellow bill with a red spot.
Size-wise, Iceland Gulls average smaller than Herring Gulls, and larger than Ring-billed Gulls. Paying close attention to wing-tip color, try to spot the immature Iceland Gull in this coastal congregation. Can you identify all 5 gull species pictured? (See the answer below).