One of Britain’s most sociable corvids, the Rook is a familiar sight on farmland across the UK. Distinguished from the Carrion Crow by the bare grey-white skin at the base of its bill and a peaked, almost shaggy appearance around the beak. Rooks nest colonially in tall trees — their large rookeries can hold hundreds of pairs and are used year after year. They probe fields in flocks for earthworms and grain, walking with a characteristic rolling, swaying gait.