Erythropus

a genus of predacious birds of the family Falconidae. The body measures approximately 30 cm long. The male has bluish black feathers and red legs. The females have a grayish back with dark horizontal stripes and a reddish underside. These birds are found in Europe and Asia; they winter in Southern Africa. There are two species, Erythropus vespertinus, which is found in the eastern steppes and forest belts as far east as the Lena River, and E. amurensis, which inhabits the southern part of Eastern Siberia and the Far East. They nest in trees, taking over the nests of rooks, ravens, and other birds. There are between four and six eggs in a clutch. These birds feed on large insects and small rodents, making them highly beneficial birds. Because their numbers are rapidly decreasing, they are a protected genus.