1. Wageningen Marine Research, IJmuiden, Netherlands
2. Bureau Waardenburg, Culemborg, Netherlands
3. SOVON Dutch Centre for Field Ornithology, Nijmegen, Netherlands
4. Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
5. Vogeltrekstation – Dutch Centre for Avian Migration and Demography, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, Netherlands
6. Faculty of Health Sciences, Institute of Medical Biology, UiT The Arctic University of Tromsø, Tromsø, Norway
7. Independent researcher, Husum, Germany
8. WWF Wadden Sea Office, Husum, Germany