Nest site characteristics and habitat preferences of the Kestrel (Falco tinnunculus) in a Mediterranean urban area

The typical habitat of the Eurasian Kestrel (Falco tinnunculus) is mainly rocky and farmland areas provided that a quantity of nests is available on quarries or rural buildings. Since Kestrels reach high density also in some European cities, urban habitats represent a model to study the effect of fragmentation, loss of original habitats, and human disturbance on consistent populations of this vulnerable species declining in farmland Europe. In the historic centre of Rome, nest sites were located 20.5 ± 8.6 m on average from the floor and showed a predominant south-east exposition. Stepwise discriminant function analysis carried out on 25 habitat proportion variables in occupied and random plots provided a model based on proportion of ruderal areas and green areas. No habitat fragmentation variables neither vegetation structure and composition variables entered a discriminant model. Using all the variables, proportion of ruderal areas and green areas provided a discriminant model that correctly classified 82% of cases. Urban Kestrels selected a habitat configuration that includes a quantity of suitable nest sites and open areas suitable for hunting lizards and insects, which are their primary prey in Rome. Protection measures in urban areas should concern nest conservation in old man-made structures and Roman ruins rather than the protection of patches of original landscape.