Herring Gull 3cy (argentatus), December 23 2010, Scheveningen, the Netherlands.

Dark bird from northern populations. Mirror on P10, and outer primaries typical blackish with well-defined white tips (indication for 3rd gen primaries, instead of 2nd gen). In general, immature plumage for this age when compared to local birds, but average for this origin. Strong clues for age often to be found in secondary pattern, which are grey based without large brown centres and without much vermiculation; and the inner primaries.