1. Department of Biology, University of Regina, Regina, SK S4S 0A2, Canada
2. Department of Mathematics and Statistics, University of Regina, Regina, SK S4S 0A2, Canada
3. Department of Geology, University of Regina, Regina, SK S4S 0A2, Canada
4. School of Environment and Sustainability, University of Saskatchewan, Saskatoon, SK S7N 5A2, Canada