1. Grimsö Wildlife Research StationDepartment of Conservation BiologySwedish University of Agricultural SciencesSE‐730 91RiddarhyttanSweden
2. Norwegian Institute for Nature ResearchTungasletta 2NO‐7485TrondheimNorway
3. Swedish Environmental Protection AgencySE‐106 48StockholmSweden
4. Department of Resource SciencesNorth‐Trøndelag CollegeBox 145NO‐7702SteinkjerNorway
5. Vaikijaur 617SE‐962 99JokkmokkSweden