Thoughts on the gull attached (and no, no more photos) would be most appreciated. Photographed at Dogsthorpe Tip, Cambs, in late July/early Aug (date escapes me). I know they're not great pics, but in the field I identified it as a Yellow-legged Gull.
Seeing Chris Batty's photos of a purported Caspian Gull (here: http://www.fyldebirdclub.org/images/cachmontage-b4.jpg) has made me think about things a bit more. The underwings of the Lancs bird are very dark which, to me, is not typical of Caspian Gull - even fresh juveniles have rather pale underwings compared to other species. See:
So, my questions are these:
1) why is the Lancs bird a Caspian Gull?
2) if the Lancs bird is a Caspian Gull, why is the Cambs bird not?