1. Department of Forestry and Wildlife Management, Faculty of Applied Ecology and Agricultural Sciences, Hedmark University College, Campus Evenstad, NO-2480 Elverum, Norway
2. Alaska Department of Fish and Game, Division of Wildlife Conservation, 1300 College Road, Fairbanks, Alaska 99701-1551, USA
3. Alaska Department of Fish and Game, Division of Wildlife Conservation, 1800 Glenn Highway, Suite 2, Palmer, Alaska 99645-6736, USA
4. Department of Wildlife, Fish and Environmental Studies, Faculty of Forest Sciences, Swedish University of Agricultural Sciences, SE-901 83, Umeå, Sweden