1cy smith candidate?, Galicia, Spain

[Stefan]

This 1cy herring gull was photographed by David Calleja Marcos at San Cibrao beach, Lugo, Galicia, NW Spain, on the 22.12.2018. It could have a northern origin, possibly from Iceland. The overall colour of the bird is quite dark, but I find the underparts could be bit more uniform and the white basal tone is shining through the upper and under tail coverts. However, the tertials appear to be quite black, uniform underwing, bill starting to be bicoloured and dark behind a neck. However, while a quite promising Smith candidate, it is hard to pinpoint any feature that makes it distinctively different from an extreme European herring gull.