On sunday I was just casually looking out at sea a five minutes walk away from home, when I noticed an odd-looking gull flying in a flock of Common Gulls. It was the same size as the others and I had at first difficulties understanding what the hell it was. After a closer examination it turned out to be a Common Gull still in juvenile plumage.

A bunch of things were odd with the bird (in finnish context at least), e.g.

* juvenile plumage, one scapular changed on the right side (as seen in the photo)
* plumage doesn't seem very worn or faded (compare the wings of the two birds in the photos)
* quite dark-bellied in my opinion
* scapulars and lesser coverts have a quite contrasting pattern, dark centres with whitish edges, not very typical I think
* pretty dark and brown greater coverts, usually more greyish (usually Common Gulls have a grey 'panel' on the inner wing in flight, but this one had an upperwing more similar to a Herring Gull for example)

Perhaps this guy has been born very late in the season or maybe it's from a different population altogether, eastern origin perhaps...

Below a photo of the bird in question plus another of a more typical looking one, both photos taken on the same day on the same spot.