Diet of the ural owl (Strix uralensis) in Slovakia

A Central European subspecies of the Ural owl Strix uralensis macroura (Wolf, 1810) is widespread in the territory of Slovakia. The work presents unpublished data on the diet of this subspecies from several territorial units of eastern and northern Slovakia, obtained from pellets and the nest linings in boxes (1 ,564 pieces). There is less data about prey brought to young in the nest but still not yet consumed (137 pieces). Published data from analysis of the stomachs of dead and shot owls come from the first six decades of the 20th century. Together with existing published data, 2,134 pieces of the diet of S. uralensis from Slovakia are evaluated. They indicate the dominance of non-forest species Microtus arvalis and a more plentiful representation of larger species of prey: Lepus europaeus, Sciurus vulgaris and Corvus sp. In upper Orava the diet of young S. uralensis also consists of frogs Rana temporaria, moles Talpa europaea and mountain species of rodents: Microtus agrestis, M. subterraneus, Sicista betulina and Arvicola amphibius. In data from the mountains of central Slovakia the Clethrionomys glareolus has high abundance, and in eastern Slovakia the Apodemus flavicollis and A. agrarius are more represented, and in the lowlands also the Cricetus cricetus. Upon evaluation ofmaterial from the entire breeding grounds of S. uralensis it can be deduced that the basic diet consist of mammals (88.6%) from the orders Soricomorpha and Rodentia. In the countries of Central Europe the species M. arvalis, M. subterraneus, A. flavicollis and Muscardinus avellanarius are more abundantly represented, and in the Baltic states the species Sorex araneus, M. agrestis, M. oeconomus and M. rossiaemeridionalis. The species S. betulina and A. agrarius occur in the diet of S. uralensis from Central Europe up through the Far East.