1. Department of Wildlife Management, North Slope Borough, Barrow, Alaska 99723, USA
2. Alaska Department of Fish and Game, Barrow, Alaska 99723, USA
3. Institute of Arctic Biology, University of Alaska Fairbanks, Fairbanks, Alaska 99775, USA
4. U.S. Fish and Wildlife Service, Fairbanks, Alaska 99774, USA
5. College of Veterinary Medicine, University of Illinois, Urbana, Illinois 61801, USA
6. Ilasgavik College, Barrow, Alaska, 99723 USA