I suspect some things come down to choice.
In my mind I cannot get beyond an either/or scenario for the controversial white-winged gull at Beddington last year. As far as I understand it is either a worn 1st summer female Glaucous-winged Gull or a first summer west coast hybrid (perhaps GWG with some AMHG influences). So far I am stuck on a equally convincing argument for both possibilities.
More here: http://peteralfrey.blogspot.com/
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