Red squirrel Sciurus vulgaris abundance in coastal cliffs in the South of Spain

Abstract

We studied the abundance of red squirrels, a medium-sized forest rodent widely distributed throughout the Palearctic, in the cliffs of Maro-Cerro Gordo (south of Spain, Málaga-Granada), a protected area with a great marine influence. We investigated the abundance of squirrels in this area in relation to two scales: (1) home range, as signs per square meter; and (2) landscape, as active nests per 1 x 1 km UTM grids. We tested the influence of land use and habitat features on the abundance of squirrels. On the home range scale, squirrel activity was higher in mature pines located near cliffs and in pines near freshwater channels. The cliffs hosted the best pine forest patches, and despite being very close to the sea, squirrels often used these as feeding areas but not as areas for building nests. On the landscape scale, squirrel nests were rarer in grids with more herbaceous crops and were more abundant in grids with longer freshwater streams. These results suggest that the squirrels in this area may have adapted to life at this site and to the marine influence via a differential use of habitat. The squirrels' use of the best feeding areas suggests saline stress is counteracted by establishing nests in humid areas away from cliffs.