1. School of Natural Resources, Univ. of Missouri Columbia MO USA
2. Dept of Biology, Univ. of Saskatchewan Saskatoon SK Canada
3. Science and Technology Branch, Prairie and Northern Wildlife Research Centre, Environment and Climate Change Canada Saskatoon SK Canada
4. Bird Conservancy of the Rockies Fort Collins CO USA
5. Science and Technology Branch, Pacific Wildlife Research Centre, Environment and Climate Change Canada Delta BC Canada
6. Dept of Forest and Conservation Sciences, Univ. of British Columbia Vancouver BC Canada
7. Inst. for Environmental Studies, Faculty of Science, Charles Univ. Prague Czech Republic