El Poblament de petits mamífers "(Insectivora i Rodentia)" a Catalunya. Requeriments ambientals i distribució geogràfica

The present paper sets out to analyse the environmental requirements of the small mammals species (insectivores and rodents) of Catalonia and the consequences of these requirements on their distribution throughout the studied territory. Basing on the particular needs of the different species, it is possible to define the following groups: the first, of Mid-European requirements, includes Sorex coronatus, Marmots marmota and Arvicola terrestris , which live in the western Pyrenees; Microtus pyrenaicus, M. nivalis and M. arvalis , found throughout the Pyrenees; and Sorex minutus, S. araneus, Neomys fodiens, Clethrionomys glareolus and M. agrestis , uniformly distributed in the Pyrenees, part of the pre-Pyrenees and in the humid eastern area. Another group is made up of species with Mediterranean requirements: Erinaceus algirus, Neomys anomalus, Suncus etruscus, Crocidura russula, Mus spretus and Microtus duodecimcostatus . Of these, the last four can be considered indicators of strictly Mediterranean conditions. They live in the Mediterranean coastal band, the Central Depression and the western area. There is another group which does not have very strict general environmental requirements, although its presence may be due to particular specific conditions. It comprises: Erinaceus europaeus, Talpa europaea, Sciurus vulgaris, Eliomys quercinus, Glis glis, Apodemus sylvaticus and Arvicola sapidus . Finally, one finds those species whose distribution is determined by man's presence: Rattus rattus, R. norvegicus and Mus musculus . In general, small mammal distribution in Catalonia is related to the physiography, climatic conditions and the dominant type of vegetation.