Glaucous-winged Gull, Larus glaucescens
Glaucous-winged Gull, 3/11/07, Half Moon Bay, San Mateo Co
Glaucous-winged Gull, adult winter, 11/20/04, Gualala River Mouth, Sonoma Co
Glaucous-winged Gull, winter adult, 12/18/04, Cliff House, San Francisco
The flying adult at the top may have the pure white head of breeding plumage already in March, and the bird shows how nearly all-white the underparts can appear. The flying bird above, at eye level, shows the more typical uniform light gray. The bird directly left is another winter adult.
Glaucous-winged Gull, third winter, 3/11/07, Venice Beach, Half Moon Bay, San Mateo Co
The bird above is third winter, with adult plumage except for dark in the tail. I first thought it might be a Glaucous, but the bill is too bulbous and has a yellow tip, not a true bicolor. The bird directly left is either second or third winter -- they can be hard to tell apart in this species.
Glaucous-winged Gull, first witner, 2/2/09, Pillar Point, San Mateo Co
Glaucous-winged Gull, first winter, 3/11/07, Venice Beach, Half Moon Bay, San Mateo Co
Glaucous-winged Gull, first summer,  8/18/05, Salinas State Beach, Monterey Co
The two above and the next two below are first winter birds, and directly left is a first summer bird, showing the very worn first-cycle plumage that produces the impression of an almost all-white gull, sometimes mistakenly taken for a Glaucous.
Glaucous-winged Gull, first winter, 2/27/07, Salinas State Beach, Monterey Co
Glaucous-winged Gull, first winter, 1/13/09, Salinas State Beach, Monterey Co
Glaucous-winged x Western (?), first winter, 1/21/06, Salinas State Beach, Monterey Co
The primary tips much darker than the upperparts mark this as probably an example of the common Glaucous-winged x Western hybrid, first-winter. Another probable example of the same hybrid below.
Glaucous-winged x Western, first winter, 1/13/09, Point Pinos, Monterey Co
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