Nest occupation and prey grabbing by saker falcon (Falco cherrug) on power lines in the province of Vojvodina (Serbia)

Research on nest occupation and prey grabbing by saker falcon (Falco cherrug) on power lines in Vojvodina (Serbia) was done in the period from 1986 to 2004. During three specially analyzed periods, saker falcon took the nests of raven (Corvus corax) in 91% of a total of 22 cases of nest occupation, and those of hooded crow (Corvus corone cornix) in only 9%. Saker falcon regularly grabs prey from different birds that occasionally or constantly spend time around power lines [Kestrel (Falco tinnunculus), hobby (Falco subbuteo), hooded crow (Corvus corone cornix), jack-daw (Corvus monedula), marsh harrier (Circus aeruginosus), hen harrier (Circus cyaneus), buzzard (Buteo buteo), and raven (Corvus corax)]. One year a studied pair of saker falcons on a power line in Donji Srem, Serbia grabbed prey from five different species of birds. Out of a total of 40 cases of prey grabbing in the period from January to December, as much 70% of the grabbed prey was taken from kestrel (Falco tinnunculus). During the winter and early spring, prey was grabbed predominantly by males; after May, prey was sometimes grabbed by females as well. Most of the grabbed prey was common vole (Microtus arvalis)