Anser anser birds geese goose group looking natural nature shallow DOF beak bill bird feathers feet foot greylag pink plumage stand England english graylag London pond preen ripples three trio water webbed bank chick family gosling greylag goose juvenile nine protect protection spring swim young Anser head neck orange ripple Sussex eye feather couple pair reflection two tail triplet adult baby communal community flock gaggle grass graze Great Britain honk meet neighbours peck vertebrate