IdentificationThe Saker falcon is a large powerful falcon, slightly bigger in size in comparison with the Peregrine falcon. The body length is between 47-55 cm, the wingspan is 105-129 cm; the tail length is 16-26 cm; weight 730-1150g. Sexes have similar plumage but females are ca. 15% larger and 40% heavier than males.
The plumage is brown above and streaked below with a paler head and whitish supercilia (eyebrow). It has a relatively small head on broad-chested, though long and otherwise slender body with long wings and long tail. In flight the silhouette is similar to the Peregrine but is with rather broad wings with blunt tips.
Biology and DistributionThe species is adapted to relatively arid, open landscapes, wooded steppe and foothills in the Palearctic region (from Eastern Europe to Western China), where it hunts ground-living mammals supplemented with birds and other prey. The Saker Falcon is physically adapted to hunting close to the ground in open terrain, combining rapid acceleration with high manoeuvrability. Thus, it prefers small and mid-sized diurnal terrestrial rodents and lagomorphs as prey, predominantly susliks.
It breeds in Eurasia across continental middle latitudes, spanning over 7,000 km from Austria in west to China in east and 3,000 km north from the Russian Federation to Iran in south; mainly in wooded steppe, steppe, sub-desert and foothills, often bordering or overlapping forests. Like other falcons the Saker is not building its own nest but it is using already build nests of other birds like Ravens, Crows, Buzzards etc. Traditionally it prefers nests on trees or on rocks, however more recently it is shifting towards electricity power pylons. The Saker falcons usually starts breeding in its third year. Its clutch usually contains 3–5 eggs, exceptionally 6. The species starts incubating in March–mid-April. The incubation period is 30–32 days. The juveniles leave the nest 45–50 days after their hatching and spend the next 4–6 weeks in their parents’ territory before disperse. Adult birds are sedentary (e.g. in Turkey), partial migrants (e.g. in Central Europe) or fully migratory (e.g. in parts of the Russian Federation), largely depending on the extent to which their food supply in breeding areas disappears in winter. It is a regular winter visitor to the central Mediterranean. The Saker Falcon regularly winters in North-east Bulgaria as well. It is also an irregular visitor to Malta. Small numbers cross the Bosporus in autumn and spring. European juveniles have been recorded as far east as Pakistan and Northwest India. Vagrants are occasionally recorded in Western and Northern Europe from Spain to Sweden and Estonia.