Biology of Saker
Sakers prefer wooded steppes, steppes, grazed grasslands with susliks. In Hungary, earlier they bred on rocks in mountains, on cavities or grassy ledges of cliffs, or in raven nests (Saker just like other falcons do not build their own nest). Nowadays, there is not a single pair breeding in mountains in Hungary. They like nest sites with a safe approaching possibility and that offers a good outlook on the territory. In the lowland nests of Imperial or White-tailed Eagles are the preferred choices, but they also breed regularly in buzzard, crow and Goshawk nests. Raven population has increased significantly from the ‘80ies and they have started to breed on pylons of high-voltage power lines in the lowland. Sakers have adapted this new nesting strategy and they are using such raven nests in increasing number. Due to this new strategy Sakers now occupies areas where nesting possibilities were limited to them.
Sakers are usually using the nests of buzzards, Ravens, crows, however sometimes they occupy the nests of Imperial Eagles, White-tailed Eagles, White Storks, herons and Cormorants, as well. Display flight begins end of January, beginning of February depending on the weather. Around the chosen nest they are very aggressive with other raptor species sometimes they chase away even the large eagles. Females lay 3-5 eggs in mid- or late March. Breeding starts after laying the second egg and it lasts 32 days. Small chicks are fed by the female only with the prey brought by the male. Young birds fledge after 6 weeks but adults teach them to hunt for 2-3 weeks more. Females become adult at the age of one year, males can start to breed only at age of two year. Pairs stay together for a lifetime.
Susliks (Spermophilus citellus) are Sakers favourite prey in Hungary. If possible, they hunt on this species, but their pigeon consumption is also significant. Susliks have quiescence in the winter thus pigeon is more important prey on the annual base. Migratory birds, most of Starlings (Sturnus vulgaris), form a big part of their diet for weeks in early spring. Adults often hunt on voles in the winter. Pairs stay together outside of breeding season as well, they sometimes hunt together. Often they nick the prey from other raptors like harriers (Circus spp.), Kestrels (Falco tinnunculus).