Changes in Numbers of Some Bird Species in the Agricultural Landscape of Eastern Poland
The studies were carried out in eastern Poland, near Siedlce (52°12'N, 22°17'E). The study area covered 788 ha of extensive agricultural landscape. The fieldwork was conducted in 1999-2003 and it comprised 7 counts per season in each year. Tendencies in changes of numbers were followed for 19 bird species. Directional increasing trends in numbers of the Serin (Serinus serinus) and Ortolan Bunting (Emberiza hortulana) were revealed. A statistically significant decreases in numbers considered the Lapwing (Vanellus vanellus), Corn Bunting (Miliaria calandra) and Whinchat (Saxicola rubetra). For the remaining 14 species — e.g. the Red-backed Shrike (Lanius collurio), Linnet (Carduelis cannabina), Goldfinch (C. chloris), Whitethroat (Sylvia communis), Yellowhammer (Emberiza citrinella) — no directional tendencies in numbers of breeding pairs were found. A comparison of tendencies in numbers of analysed species with tendencies observed in western Europe and in western Poland showed that the status of birds in the agricultural landscape of eastern Poland was much better. This has probably been caused by lower intensity of farming practice and more diverse mosaic of habitats.