Rocks and trees: habitat response of Tawny Owls Strix aluco in semiarid landscapes

Abstract

Breeding territories of Tawny Owls Strix aluco were surveyed in Murcia, SE Spain, in 1992 using imitating calls. In all, 178 territories were detected and although regional density was low, local breeding densities were as high as 17 pairs/100 km2 . The response of Tawny Owls to habitat characteristics in this semiarid region was related to the scale of the study. The slope followed by the forest cover were the best predictor variables for the Tawny Owl's breeding density at a 9 km2 scale, whereas forest cover and the size of the forests were the best predictor variables when the scale was increased to 100 km2 . Owls seemed to select rugged rocky areas for breeding owing to the lack of suitable holes for nesting in the pine forest, but also required a certain amount of forest for hunting. Our results suggest that Tawny Owls might be very flexible with respect to habitat selection, even at the limits of its distribution range.