Greylag Goose, Anser anser

Greylag Goose, 5/14/11, Regent's Park, London
The ancestor of most domestic geese worldwide, the Greylag is an common resident bird in Britain, in the south partly through re-introduction.

Greylag Goose, flying, 5/6/11, Regent's Park, London

Greylag Goose, 5/9/11, Regent's Park, London
Note the bicolored bill, black and pink, which is not usual among Greylags. The Asian subspecies rubrirostris has a pink bill, compared to the orange bill of the European nominate subspecies, seen in the two pictures above.