Caspian gulls from Ukraine

Underwing pattern is one of the better characters for separating first year Caspian and Herring Gulls. The following photos demonstrate individual variation of Caspian Gull. All are taken in the southern Ukraine, between 2 and 8 August 2001. They are ordered roughly from the palest to the darkest. Even the darkest are quite clearly different from Herring Gull: there are still some uniform whitish areas, especially on the median coverts, and the barring is more contrasting. Typically the bars on the axillaries are heaviest distally and the bases are almost unbarred.