NESTING DISPERSION OF A BLACK KITE POPULATION IN RELATION TO LOCATIONOF RABBIT WARRENS

Previous studies have shown that the rabbit (Oryctolagus cuniculus) is the main prey of the Black Kite (Milvus migrans) in Matasgordas (Dona na National Park, southwestern Spain), and that the reproductive succe ss of pairs is enhanced with increasing rabbit consumption. In our stu dy area, rabbits live mainly in large warrens patchily distributed acr oss the breeding area of Black Kites. Rabbit consumption was higher fo r Black Kite pairs having warren entrances close to their nests. Durin g the 3 years of the study, this population of Black Kites suffered a considerable increase. New pairs in the area selected nesting trees in side areas with a high density of rabbits. The pattern of Black Kite a ggregation in our study area, where they breed in a ''colony'' with a population density among the highest recorded, can be explained, at le ast partially, by rabbit aggregation. Defense of feeding resources cou ld help to explain the territorial behavior of Black Kites. Colonialit y and feeding territoriality are not mutually exclusive.