Habitat use and diet of the red foxVulpes vulpes in an agricultural landscape in Poland

Red foxVulpes vulpes density, diet and den site selection were studied in a unwooded farmland of western Poland. During years 1999–2000 snow tracking was performed, and in 1999 dens were counted. Estimated population densities based on snow tracking were 2.1 and 1.79 individuals/km² respectively, while den counts gave a value of 2.20 individuals/km². Almost all dens were located on steep slopes, mainly on banks of drainage ditches (51%) and marsh banks (18%). Foxes markedly preferred southern exposure, while western slopes were avoided. The relatively high number of dens, their clumped distribution and the small number of breeding dens show that the studied population was organised in 5 clans. 26% of the dens were used only temporarily indicating that some of individuals use more than one den. Scat analyses revealed a high frequency of rodents, birds (mainly poultry) and garbage items in fox food (65.6, 47.9, 16.0% occurrence in scats, respectively). Fox adaptation to anthropogenic food sources and change in den site selection are discussed as main factors responsible for the occupation of farmland and in consequence, for the increase of fox densities in Poland.