Larus argentatus argentatus & L. a. argentatus, upper-part coloration in Scandinavia.

Illustration based on E. K. Barth: The circumpolar systematics of Larus argentatus and Larus fuscus with special reference to the Norwegian populations, IN: Contribution No. 86, Zoological Museum, University of Oslo.
Although figures have been prepared with most care, I take full responsibility for all errors in any chart and table.

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