This photo shows the bird’s mantle shade, which is a little darker than the larger Herring Gulls on the right. The red and black marks on the bill are noticeable here along with the dark eye on the clean white, rounded head.

California Gull — Lake Nockamixon, Bucks County; March 25, 2006. Photos by Gerry Dewaghe.

This photo shows the bird’s lighter mantle color in comparison to the two similar-sized Lesser Black-backed Gulls on the right.