Species Composition and Population Structure of Rodent Communities in Different Habitats in the Lozenska Mountain, Bulgaria

The aim of this study is to assess the rodent community as a key component of agricultural and semi-natural ecosystems. Small mammals were caught on the territory of the Lozenska Mountain, western Bulgaria, in various natural and agricultural habitats. For this purpose, natural areas such as xerothermic oak forests, hygromesophytic secondary grasslands and their border areas as well as corn and alfalfa fields were examined. Species composition varied across the habitats, with a total catch of four rodent species. Population number, sex and age structure of the house mouse (Mus musculus), wood mouse (Apodmus sp.), bank vole (Myodes glareolus) and common vole (Microtus arvalis) were studied. Only two species (M. glareolus and Apodemus sp.) were found in the oak forest. The secondary grasslands also contained two rodent species (Apodemus sp. and Microtus arvalis). The agricultural habitats contained each a rodent community of three species (Apodemus sp., Microtus arvalis and Mus musculus) but the former two represented with low estimated population numbers, possibly due to animals visiting these fields for feeding and originating from neighbouring habitats. The populations of the four rodent species had balanced sex and age structure.