gawron Corvus frugilegus

Large, glossy black crow. Adult is easily passed off as another crow species unless you see the diagnostic pale patch at the base of the bill. Juvenile lacks a pale bill base and is very similar to Carrion Crow, but bill is a little more tapered; pale bill base develops late in its first winter. Inhabits farmland and other semiopen areas with hedges and groups of tall trees, where nests in rookeries. Forages on ground, usually in flocks, and associates readily with crows and jackdaws. Rook calls are higher pitched and less rolling than other crow calls.