Factors affecting the distribution of Sorex samniticus , an endemic Italian shrew, in an heterogeneous landscape

We studied the factors affecting the distribution of an endemic shrew Sorex samniticus Altobello, 1926 in the Province of Siena, central Italy. Distribution data were obtained by examining pellets from 31 barn owl Tyto alba sites (roosts) over a period spanning from 1974 to 2005. We constructed a model using logistic regression analysis on presence/absence data. Results show that an increase in forest dominated by Quercus cerris and Castanea sativa led to the local extinction of this species. Results were confirmed through the examination of one box, with 3044 prey items deposited in layers, that documents the expansion of the species in that area following increased logging of Quercus cerris and Castanea sativa forests. Cessation of logging has again led to the absence of the species from the area. We discuss these results from the perspective of ecological network planning, showing that utilisation of non-detailed maps, such as Corine Land Cover, that do not distinguish between the various kind of broadleaved forests is inadequate to describe the finer grade of habitat selection of this small mammal.