Aims: The Booted Eagle Hieraaetus pennatus is a poorly known raptor that has bred in Catalonia at least since 1989, when the first nest was found. Its confirmed breeding population has increased from 1 breeding pair in 1989 to 13 breeding pairs in 2001. The present study provides information about the population and the nesting habitat selection of the Booted Eagle in central Catalonia from 1990-2001.
Location: central Catalonia.
Methods: The data of presence of the Booted eagle in the studied area was obtained from April to August (1990-2001). The representation of the located nests has been made by means of a UTM projection square grid 10x10 km. To describe the characteristics of the nesting habitat, the occupied territories have been compared with equal number of random sites by means of 16 variables using the t-test and circular statistics.
Results: Of 41 UTM square 10x10 km prospected, reproduction has been verified in 9, with 11 located breeding pairs. Potentially breeding pairs have been detected in other 6 squares and the species has been detected during the breeding season in other 13 square. In central Catalonia, Booted Eagles breeds significantly in places away from country houses. However, this species tolerates a more significant presence of paved and unpaved roads near its nesting area than would occur at random points. Birds nest in big trees (preferably Black Pine) of extensive, closed and shady woods, significantly orientated between 31.5°N to 45°N.
Conclusions: In the area studied, the species settles down preferably far from the human settlement, although it perfectly tolerates the presence of highways and forest paths. Contrary to what happens in other Iberian areas, where the species breeds in solitary trees and in small groups of trees, in central Catalonia the Booted Eagle breeds in big trees of extensive, closed and shady forests of Black Pine, facing north. The orientation of the nest is probably influenced by the wind direction, the altitude and perhaps by the solar radiation.