| Richard Millington was most helpful (again) in diagnosing this bird. It turned up with a big influx of northern gulls; there were Iceland Gulls in various parts of the UK, Ireland and Holland, including this bird at Milton and also many argentatus at Milton, including some very pale birds with patterned tertials. Although its shape is very like a Herring Gull, and its plumage and head structure is extremely similar to this bird, which was present at the same time, the primaries, with sub-terminal chevrons are a trait of a juvenile white-winged gull. Although it is not uncommon to see northern argentatuswith a white fringe to the primaries, they do not exhibit this trait. Received wisdom has it that Iceland x Herring Gull does not exist, but this bird does not look like the normal run of Glaucous x Herring hybrids that turn up and presumably originate in Iceland (hyperboreus x argenteus). Therefore, given the fact also that there were no Glaucous Gulls involved in this northerly influx, then it is tempting to conclude that this is a hybrid Glaucous x argentatus .
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Leucistic Herring Gull?
Glaucous x Herring Gull hybrids
