Rooks are mainly resident birds, but the northernmost populations may migrate southwards to avoid the harshest winter conditions.
The birds form flocks in winter, often in the company of other Corvus species or jackdaws. They return to their rookeries, and breeding takes place in spring. They forage on arable land and pasture, probing the ground with their strong bills and feeding largely on grubs and soil-based invertebrates, but they also consume cereals and other plant material. Historically, farmers have accused the birds of damaging their crops and have made efforts to drive them away or kill them. Like other corvids, they are intelligent birds with complex behavioural traits and an ability to solve simple problems.

