1. Wyoming Cooperative Fish and Wildlife Research Unit, Department of Zoology and Physiology University of Wyoming Laramie Wyoming USA
2. Program in Ecology University of Wyoming Laramie Wyoming USA
3. Haub School of Environment and Natural Resources University of Wyoming Laramie Wyoming USA
4. U.S. Geological Survey, Wyoming Cooperative Fish and Wildlife Research Unit, Department of Zoology and Physiology University of Wyoming Laramie Wyoming USA