1. Faculty of Agriculture, Institute of Animal Sciences and Wildlife Management, University of Szeged, Hódmezővásárhely, Hungary
2. CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Laboratório Associado, Universidade do Porto, Vairão, Portugal
3. CIBIO/InBIO, Centro de Investigação em Biodiversidade e Recursos Genéticos, Laboratório Associado, Instituto Superior de Agronomia, Universidade de Lisboa, Lisboa, Portugal
4. School of Environmental Sciences, University of East Anglia, Norwich, UK
5. Department of Functional and Evolutionary Ecology (EEZA-CSIC), Almería, Spain
6. Institute of Ornithology, Croatian Academy of Sciences and Arts, Zagreb, Croatia
7. Ukrainian Society for the Protection of Birds, BirdLife Ukraine, Kyiv, Ukraine
8. BSPB – BirdLife Bulgaria, Sofia, Bulgaria
9. cE3c – Centro de Ecologia, Evolução e Alterações Ambientais, Faculdade de Ciências, Universidade de Lisboa, Lisboa, Portugal
10. CORACIAS – SROPU, Viterbo, Italy
11. A Rocha France, TOURRETTES-SUR-LOUP, France
12. Institut de recherche de la Tour du Valat, Arles, France
13. PSL Research University, CEFE UMR 5175, CNRS, Université de Montpellier, Université Paul-Valéry Montpellier, EPHE, Montpellier, France
14. BirdLife Hungary, Budapest, Hungary
15. Centre for Ecological Research, Danube Research Institute, Budapest, Hungary
16. Senckenberg Deutsches Entomologisches Institut, Müncheberg, Germany