1. Department of Collective Behaviour Max Planck Institute of Animal Behavior Constance Germany
2. Centre for the Advanced Study of Collective Behaviour University of Konstanz Constance Germany
3. Department of Biology University of Konstanz Constance Germany
4. Department of Evolutionary Biology and Environmental Science University of Zurich Zurich Switzerland
5. Department of Migration Max Planck Institute of Animal Behavior Radolfzell Germany
6. Mpala Research Centre Nanyuki Kenya
7. Division of Ecology and Evolution, Research School of Biology Australian National University Canberra Australia
8. Department of Ornithology National Museums of Kenya Nairobi Kenya