Ornis Hungarica. vol.7. (1997) p.49-53.
A population of diurnal raptors on Dravsko polje (NE Slovenia)
Between 1985 and 1996 quantitative data were collected about raptor populations on DraNsko poije (46°25'N, 15°45'E) in Slovenia. A total of 8 (including 2 possible breeders) species were reported to occur in the area under study. The average bird density was 2.8 pairs/10 km2. The greater part of the breeding community is comprised of two species i.e. Kestrel Falco tinnunculus and Common Buzzard Buteo buteo. Breeding density of the Common Buzzard is up to 0.66 pair/10 km2 and density of the Kestrel up to1.43 pair/1O km2. The breeding population of Kestrel decreased steadily during 12 years of study, from about 30 nests at the start (1985-1986) to about 15 at the end of the study (1995-1996). The changes are significant. Breeding communities were also analysed in relation to the migratory habits of birds of prey. The density of the breeding community on Dravsko polje depended primarily on the density of resident raptors (average value: 2.2 pairs/km2). The differences between numbers of pairs according to migratory habits is highly significant.