Habitat suitability and nest-site selection of short-Toed eagle Circaetus gallicus in Tolfa Mountains (Central Italy)

Abstract

The availability of a suitable nesting site can be an important limiting factor for the reproduction of birds of prey, which are highly influenced by forest management and exploitation activities. Among them, the short-Toed eagle (Circaetus gallicus) seems to tolerate logging activities carried out with traditional practices. This study aimed to investigate the habitat selection of 29 territorial pairs of this species in the Tolfa Mountains (Central Italy). Using Generalized Linear Models and the Information-Theoretic Approach, we compared the environmental features (i.e. land cover and topography) that characterize nesting sites in the study area. Additionally, we described the nest-site selection of the species by characterizing nine detected nests and comparing their characteristics with those of an equivalent number of nearby randomly selected sites. We found that, as expected, the short-Toed eagle settles on hillsides covered by broad-leaved forests (both evergreen and deciduous) with open areas and away from agricultural areas. Moreover, the nests were found on steeper slopes, on trees extensively covered with climbing plants, possibly to hide them from predators and human disturbance. Our results suggest that, for the conservation of the short-Toed eagle, careful management of woodland coppicing is required, as well as greater control of human disturbance.