1. Illinois River Biological Station, Illinois Natural History Survey, Prairie Research Institute, University of Illinois at Urbana–ChampaignHavanaIL62644
2. Illinois Department of Natural ResourcesSilver Springs State Fish and Wildlife AreaYorkvilleIL60560
3. Wisconsin Department of Natural ResourcesEscanaba Lake Research StationBoulder JunctionWI54512
4. Illinois River Biological Station, Illinois Natural History Survey, Prairie Research Institute, University of Illinois at Urbana—ChampaignHavanaIL62644
5. Illinois Department of Natural ResourcesSpringfieldIL62702