1. National Wildlife Research Centre, Environment and Climate Change Canada, Ottawa, ON K1A 0H3, Canada
2. Canadian Museum of Nature, P. O. Box 3443, Station D, Ottawa, ON K1P 6P4, Canada
3. Department of Geography and Planning, University of Saskatchewan, 105 Kirk Hall, 117 Science Place, Saskatoon, SK S7N 5C8, Canada
4. Department of Biology, Carleton University, Ottawa, ON K1S 5B6, Canada
5. Freshwater Institute, Fisheries and Oceans Canada, 501 University Crescent, Winnipeg, MB R3T 2N6 Canada