Introduction European rabies models are mainly based on red fox Vulpes vulpes (Linnaeus, 1758) ecology, because the fox has been the main vector of the disease in Continental Europe. In north-east Europe, like Finland, the raccoon dog Nyctereu- tes procyonoides (Gray, 1834) is an important member of the carnivore community, and its sig- nificance as a vector of rabies has rapidly in- creased during the last few years (WHO 2003). The raccoon dog was also the most common vec- tor/victim of the disease during an epizootic of sylvatic rabies in southern Finland in the late 1980s (Westerling 1991). Red foxes, badgers Meles meles (Linnaeus, 1758) and domestic cats Felis silvestris catus (Schreber, 1777) were the other species affected. New rabies models, based on the local carnivore community with several vector species, are needed for north-east Europe. To build such models, we require data on the home ranges, densities, dispersal and habitat utilisation patterns of medium-sized carnivores, and inter-specific contact rates. Home range size is a basic parametric; it is generally negatively [1] Acta Theriologica 51 (1): 1–13, 2006. PL ISSN 0001–7051 Home ranges and densities of medium-sized carnivores in south-east Finland, with special reference to rabies spread Kaarina KAUHALA, Katja HOLMALA, Wiebke LAMMERS and Julia SCHREGEL Kauhala K., Holmala K., Lammers W. and Schregel J. 2006. Home ranges and densities of medium-sized carnivores in south-east Finland, with special reference to rabies spread. Acta Theriologica 51: 1–13. Home ranges and densities of medium-sized carnivores were studied in south-east Finland by radio tracking. The species studied included potential vectors of rabies: the raccoon dog Nyctereutes procyonoides (Gray, 1834), red fox Vulpes vulpes (Linnaeus, 1758), European badger Meles meles (Linnaeus, 1758) and domestic cat Felis silvestris catus (Schreber, 1777). Home ranges of badgers were largest (mean 14.7 km 2 ) and those of cats smallest (1.5 km 2 ). Home ranges overlapped largely, both within and between species. Most home ranges were larger and population densities lower in south-east Finland compared with those in Western Europe. The pooled density of medium-sized carnivores with overlapping home ranges was, however, high, which may indicate a high risk of a rabies epizootic in this multi-host community. Rabies might also spread rapidly to new areas, because of the large home ranges and, consequently, long dispersal distances. Finnish Game and Fisheries Research Institute, Turku Game and Fisheries Research, Itäinen Pitkäkatu 3 A, FIN-20520 Turku, Finland, e-mail: kaarina.kauhala@rktl.fi (KK); Kunnaantie 18 C 12, 01370 Vantaa, Finland (KH); Kurt-Eisner-Str.81, 04275 Leipzig, Germany (WL); Tervakuk- kakuja 1 as 36, FIN-90580 Oulu, Finland (JS) Key words: Nyctereutes procyonoides, Vulpes vulpes, Meles meles, Felis silvestris catus, home range, density, rabies