With such a large amount of dark in primary tips, such dense brown-mottled pattern in greater coverts and dark wawing in under tail-coverts (recalling, in this case, a well-marked 1-year American Herring Gull), this bird is a clear kumlieni.

There caan be no doubt about that. Good tal pattern as well. Would have been nice to see a flightshot of this bird! Any of those Matthieu?

Thanks you, for your identification answers ! Yes Jan I have flightshot of this bird. I have sent you by email.