Comparative study of Spanish and Italian terrestrial small mammal coenoses from different biotopes in Mediterranean peninsular tip regions

摘要

A comparison of terrestrial small mammal coenoses belonging to 9 different biotopes in the tips of the Iberian (Andalusia) and Italian (Calabria) peninsulas was conducted using the pitfall trapping method. The habitat types were defined as follows:marshlands, pine woods (Pinus pinea), xerophytic Mediterranean shrublands, arid streams, stream borders, Mediterranean Maquis, Holm Oak woods (Quercus ilex) and Cork Oak woods (Quercus suber). The influence of both habitat type and peninsular effect on the composition of small mammal coenoses was analysed. In Southern Italy, 203 specimens belonging to 7 species were trapped (Suncus etruscus, Crocidura suaveolens, C. leucodon, Microtus savii, Apodemus sylvaticus, A. flavicollis and Mus musculus domesticus). In Southern Spain 428 specimens belonging to 5 species were trapped (S. etruscus, Crocidura russula, Microtus duodecimcostatus, Apodemus sylvaticus and Mus spretus). The relative density of small mammals occurring in the 9 Spanish sampling stations was twice that recorded in the Italian stations. However the number of species recorded in the different biotopes showed similar mean values, ranging from 3 to 5 in Andalusia and from 3 to 6 in Calabria. A. sylvaticus was the dominant species in the Calabrian stations, whereas C. russula prevailed in Andalusia. The biotic diversity values are very similar in the Calabrian and Andalusian biotopes. In contrast, the insectivore/rodent ratio was always higher in Andalusia. The more xerophytic biotopes showedgreater similarities between the communities in Southern Spain and Southern Italy, while the cooler biotopes differed between these 2 peninsulas.