Common Black-headed Gull (Larus ridibundus)

Note; a 1Cy bird in August! Note; the light brown mantle and parts of back; darkish greater covers of upper wing; dark trailing edge to flight feathers, pure show white tail with a diagnostic broad black band at tip; note also that in this plumage the outer white primaries have dark areas on the "central-lower" part of these feathers (only in this plumage). August plumage. Copyright © Louis A. Hansen

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