1. MEDRAPTORS (Mediterranean Raptor Migration Network); via Mario Fioretti 18 00152 Rome Italy
2. Fundación Migres; Ctra. N-340, Km. 96.7, Huerta Grande, Pelayo Algeciras E-11390 Cádiz Spain
3. Section of Animal Biology; Department STEBICEF; University of Palermo; Via Archirafi 18 90123 Palermo Italy
4. Ethology and Biodiversity Conservation; Doñana Biological Station; CSIC; c/ Américo Vespucio s/n, E-41092 Seville Spain