Common Gull, Larus canus
Common Gulls are actually not very common at all but they are often overlooked when present.
The local park has been displaying 'DANGER THIN ICE' notices since the autumn, but today the warning was for real. Pity the birds can't read though as I saw a coot land on it and then fall through with a look of surprise.
This thicker raft of ice was providing a refuge for a flock of black-headed gulls who just wanted to sleep or preen. They are in various stages of change from winter to summer plumage but they always have at least a small patch of black at all times. They also have prominently red legs.
. . . except one.
Just left of centre is a bird with no black on its head and greeny-grey legs. That is a common gull.
Around here you can generally see one or two common gulls hanging out with the b-hgs.