1. South Iceland Research Centre University of Iceland Lindarbraut 4 Laugarvatn IS‐840 Iceland
2. Department of Biology & CESAM University of Aveiro Campus de Santiago Aveiro 3810‐193 Portugal
3. Institute of Ecology and Earth Sciences, University of Tartu Liivi 2 Tartu 50409 Estonia
4. BirdEyes, Centre for Global Ecological Change at the Faculties of Science & Engineering and Campus Fryslân University of Groningen Zaailand 110 Leeuwarden 8911 BN The Netherlands
5. Department of Coastal Systems, NIOZ Royal Netherlands Institute for Sea Research PO Box 59 Den Burg, Texel 1790 AB The Netherlands
6. Rudi Drent Chair in Global Flyway Ecology Groningen Institute for Evolutionary Life Sciences (GELIFES), University of Groningen PO Box 11103 Groningen 9700 CC The Netherlands