1. Department of Earth and Environmental SciencesUniversity of Pavia Pavia Italy
2. Department of BiologyUniversity of Florence Florence Italy
3. Department of Life SciencesUniversity of Siena Siena Italy
4. Department of Zoology and Animal Cell Biology, Zoology LaboratoryUniversity of the Basque Country (UPV/EHU) Vitoria‐Gasteiz Spain
5. Systematics, Biogeography and Population Dynamics Research Group, Lascaray Research CenterUniversity of the Basque Country (UPV/EHU) Vitoria‐Gasteiz Spain
6. Monitoring Department, Swiss Ornithological Institute Lucerne Switzerland