Viking Gull ~ Larus hypergentatus
Its a hybrid, of mixed parentage, a cross between Glaucous Gull and Herring Gull.
It could be leucistic ..
It could well be within variation and just be a pale variant of Herring Gull ..
There are however a few features that I believe make a case for a hybrid rather than just a pale bird.
Scapular pattern with the terminal half moon shape
Tertial pattern with bold markings
Primaries with pale edges
Note ... How different the under-wing looks with the way the light hits it !!
Nothing to do with the hybrid but striking how the light changes the way the wing looks ...
The narrow pale markings at the base of the tail band
Tiny dark markings to end each primary & secondary
Is there features strong enough to backup a case for Glaucous hybrid even though they are subtle.
Or is it well within variation ..
Lets see if anybody will comment !!
Here's a few links