1. Department of Fisheries and Wildlife Michigan St. University 480 Wilson Rd East Lansing MI 48824 USA
2. U.S. Geological Survey, Pennsylvania Cooperative Fish & Wildlife Research Unit Pennsylvania State University 402 Forest Resources Building University Park PA 16802 USA
3. Department of Zoology and Physiology University of Wyoming Laramie WY 82071 USA
4. Department of Biological Science University of Montreal Montreal Quebec Canada H3C 3J7
5. Trout Lake Research Station Univ. of Wisconsin 3110 Trout Lake Station Drive Boulder Junction WI 54512 USA
6. Upper Midwest Water Science Center U.S. Geological Survey 8505 Research Way Middleton WI 53562 USA