1. Illinois Natural History Survey, Prairie Research Institute, University of Illinois, Champaign, IL 61820, USA
2. National Great Rivers Research and Education Center, One Confluence Way, East Alton, IL 62024, USA
3. School of Environment and Natural Resources, The Ohio State University, 2021 Coffey Road, 210 Kottman Hall, Columbus, OH 43210, USA
4. Analysis and Project Support Division, Greater Atlantic Regional Fisheries Office, National Oceanic and Atmospheric Administration, Gloucester, MA 01930, USA