INHS Technical Report: 2015(11):1–219 + iii Date of Issue: 25 May 2015 ECOLOGY OF THE SMOOTH SOFTSHELL IN THE KASKASKIA RIVER: IMPLICATIONS FOR MANAGING FLOWS IN AN ALTERED SYSTEM Submitted by: Jason P. Ross, Michael J. Dreslik, and Robert Bluett Prepared for: Illinois Department of Natural Resources One Natural Resources Way Springfield, Illinois 62702-1271 Fund Title – IDNR T-87-D-1 Restricted Access – T&E Species Locations Prairie Research Institute, University of Illinois Urbana-Champaign Brian D. Anderson, Executive Director Illinois Natural History Survey Geoffrey A. Levin, Director 1816 South Oak Street Champaign, IL 61820 217-333-6830 Table of Contents INTRODUCTION ............................................................................................................... 1 OBJECTIVES .................................................................................................................1 HABITAT AND SPATIAL NEEDS ..................................................................................................... 1 COMMUNITY AND POPULATION STRUCTURE ................................................................................ 2 BEHAVIORAL RESPONSES ............................................................................................................. 2 PHENOLOGICAL RISKS .................................................................................................................. 2 MANAGEMENT RESPONSES ........................................................................................................... 3 STUDY SITE .................................................................................................................3 METHODS ........................................................................................................................ 4 GENERAL METHODOLOGY ............................................................................................................ 4 Trapping ................................................................................................................................... 4 Individual Turtles ..................................................................................................................... 4 Radio Telemetry ...................................................................................................................... 5 Location Data ........................................................................................................................... 5 Environmental Data ................................................................................................................. 5 Behavioral Data ....................................................................................................................... 6 DATA ANALYSIS ........................................................................................................................... 6 Community and Population Structure ...................................................................................... 6 Movement ................................................................................................................................ 6 Home Range ............................................................................................................................ 7 Habitat Use .............................................................................................................................. 8 Survival .................................................................................................................................. 10 RESULTS ....................................................................................................................10 TRAPPING ................................................................................................................................... 10 POPULATION STRUCTURE ........................................................................................................... 11 Apalone mutica ...................................................................................................................... 11 Apalone spinifera ................................................................................................................... 11 Chelydra serpentina ............................................................................................................... 11 Chrysemys picta ..................................................................................................................... 11 Graptemys geographica ......................................................................................................... 12 Graptemys ouachitensis ......................................................................................................... 12 i Sternotherus odoratus ............................................................................................................ 12 Trachemys scripta .................................................................................................................. 12 COMMUNITY PARAMETERS ......................................................................................................... 12 RADIO TELEMETRY .................................................................................................................... 13 MOVEMENT ................................................................................................................................ 13 HOME RANGE ............................................................................................................................. 14 HABITAT USE ............................................................................................................................. 15 SURVIVAL................................................................................................................................... 17 CONCLUSIONS ............................................................................................................... 17 HABITAT AND SPATIAL NEEDS ................................................................................................... 17 Extent - Movement ................................................................................................................ 17 Extent – Home Range ............................................................................................................ 20 Fragmentation ........................................................................................................................ 22 Composition-Structure ........................................................................................................... 23 COMMUNITY AND POPULATION STRUCTURE .............................................................................. 25 Competitors ............................................................................................................................ 25 Recruitment ............................................................................................................................ 26 Mortality ................................................................................................................................ 27 BEHAVIORAL RESPONSES ........................................................................................................... 28 Activity Levels and Behavioral Shifts ................................................................................... 28 Thermal Challenges ............................................................................................................... 29 PHENOLOGICAL RISKS ................................................................................................................ 30 Nesting ................................................................................................................................... 30 Overwintering ........................................................................................................................ 30 MANAGEMENT RESPONSES ........................................................................................... 31 ACKNOWLEDGEMENTS ................................................................................................. 33 LITERATURE CITED ...................................................................................................34 TABLES ......................................................................................................................... 40 FIGURES ........................................................................................................................ 60 MAPS.........................................................................................................................92 PLATES .................................................................................................................... 133 APPENDIX I – RADIO-LOCATIONS ............................................................................... 142 2 APPENDIX II – TURTLE CAPTURES ........................................................................... 184 APPENDIX III – TRAP LOCATIONS .............................................................................. 206 APPENDIX IV – RADIO-TRACKED TURTLE SURVIVAL NOTES ................................... 218 3 INTRODUCTION Riverine ecosystems are vital for many at-risk species (Allan and Flecker, 1993), yet widespread degradation in the United States has left few rivers with outstanding natural qualities (Palmer, 1994). Such degradation