Small mammals in the diet of the Tawny Owl [Strix aluco L.] in Central European Lowland

We analysed the variation of small mammal species composition in the Tawny Owl Strix aluco L. diet in forest habitats of Central European Lowland. We used published and unpublished materials from forest-dominated landscapes in Lithuania (n = 7 locations), Poland (n = 8) and East Germany (n = 1); marginal localities were ca. 870 km from each other. We recorded that in Central European Lowland the proportion of Arvicolidae in the Tawny Owl diet significantly increased, while that of Muridae decreased toward north-east. The proportion of less common rodent species (including Gliridae and Sicita betulina Pallas) in the diet also increased significantly toward NE. We did not record any trend of small mammals diversity along the analysed transect. We suggest that the change of Arvicolidae to Muridae ratio toward north-east can be caused by the replacement of mice with boreal vole species in small mammal community. Small mammal diversity in Central Europe is subject of discussion.