The rook (Corbus frugilegus) is a bird of the crow (Corvidae) family of the order Passeriformes. Rooks are social birds, frequently seen in farmland in large flocks. They have glossy black plumage, and the adult has a bare, white facial patch at the base of the long bill, which is absent in the young. The rook's nest is a large, made of sticks lined with grass, moss and leaves, and is built high in a tree. Rooks eat worms, beetle larvae, seeds, grain and roots, carrion and general human waste. Research Rook