Feeding ecology of a nesting population of the Common Buzzard (Buteo buteo) in the Upper Nitra Region, Central Slovakia

During routine checks of the nests of the Common Buzzard in the Upper Nitra region (Central Slovakia) we collected food remains and recorded all prey given to the nestlings. We present results from the period 2006-2008. 606 food items were determined, comprising mainly mammals (67%). Birds were also frequent (17%), less so amphibians and reptiles (7%) and invertebrates (10%). During the rodent population peak in 2007, Buzzard pairs nesting in the valley preyed mainly on Microtus arvalis, whereas pairs living at the rim of the valley fed on Myodes glareolus and Talpa europaea, and higher in the Vtáčnik Mts birds fed on Apodemus flavicollis. After a massive decline in the rodent population in the following year 2008, the survival rate of the nestlings was very low and the proportion of invertebrates in their diet increased. Birds that were most frequently preyed upon included juvenile Turdus philomelos and Garrulus glandarius, prey identified from amphibian was mainly Bufo bufo, and from reptile prey was largely Anguis fragilis.