Rook

Corvus frugilegus subfamily

Corvinae taxonomy

Corvus frugilegus Linnaeus, 1758, Sweden. Two subspecies. other common names

French: Corbeau freux; German: Saatkrähe; Spanish: Graja Común.

physical characteristics

18.33 in (47 cm); 11.8-18.58 oz (337-531 g). Entire plumage is black and highly glossed with metallic blue, green, and purple. Base of the bill, chin, and loral region are bare, giving the forecrown a slightly peaked appearance. Bill is whitish at the base shading to dusky over the terminal half. Legs and feet are black.

distribution

In all but the most mountainous areas of Europe and Asia. habitat

Farmland with scattered trees and wooded steppe. behavior

Significant fall migrant, flying by day from northern Europe and Asia, to western Europe, the Middle East, and southern Asia. In the Seine-et-Marne district of France, the breeding population was estimated at 10,000; the winter population 500,000.

feeding ecology and diet

Soil feeder on invertebrates, seed, grain.

reproductive biology

Nests colonially in rookeries; there are generally at least 20 nests densely clustered around the tops of several trees. Nests used repeatedly in successive years. Lays two to seven eggs in grass and leaf cup within bulky stick nest. Incubation 16-18 days; fledging 32-33 days.

conservation status

Not threatened. Abundant to localized in Europe. Evidence of decline in eastern Asia.

significance to humans

Often persecuted because of its tendency to feed on cereal seed. ♦

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