Data Summary Report: Nekton of Sarasota Bay and a Comparison of Nekton Community Structure in Adjacent Southwest Florida Estuaries for Year Four (June 2012 – April 2013) T.C. MacDonald; R.F. Jones; E. Weather; R.H. McMichael, Jr. Florida Fish and Wildlife Conservation Commission Fish and Wildlife Research Institute 100 Eighth Avenue Southeast St. Petersburg, Florida 33701-5095 Prepared for Sarasota Bay Estuary Program 111 S. Orange Avenue, Suite 200W Sarasota, Florida 34236 May 30, 2014 TABLE OF CONTENTS TABLE OF CONTENTS ................................................................................................................................. i LIST OF FIGURES ........................................................................................................................................ v LIST OF TABLES ......................................................................................................................................... ix ACKNOWLEDGEMENTS ............................................................................................................................ xi SUMMARY .................................................................................................................................................. xiii INTRODUCTION ........................................................................................................................................... 1 METHODS .................................................................................................................................................... 2 Study Area ................................................................................................................................................ 2 Sampling Design ...................................................................................................................................... 3 Gear Specifications and Deployment ....................................................................................................... 6 Sample Processing .................................................................................................................................. 7 Nekton Community Analysis .................................................................................................................... 9 Overall abundance ............................................................................................................................... 9 Multivariate analysis ........................................................................................................................... 10 Bray-Curtis similarity calculation ........................................................................................................ 12 Non-metric multidimensional scaling (MDS) and Similarity Percentage Analysis (SIMPER) ............ 12 Mercury Content Analysis ...................................................................................................................... 13 RESULTS and DISCUSSION ..................................................................................................................... 15 Physiochemical conditions ..................................................................................................................... 15 Composition of overall nekton community ............................................................................................. 20 Shallow water habitats sampled with 21.3-m seines .......................................................................... 21 Nearshore habitats sampled with 183-m haul seines ........................................................................ 25 Deeper-water habitats sampled with 6.1-m otter trawls ..................................................................... 28 Species Profiles...................................................................................................................................... 31 Pink Shrimp, Farfantepenaeus duorarum .......................................................................................... 33 Blue crab, Callinectes sapidus ........................................................................................................... 39 Ladyfish, Elops saurus ....................................................................................................................... 43 Bay anchovy, Anchoa mitchilli ............................................................................................................ 45 Common Snook, Centropomus undecimalis ...................................................................................... 49 Gray Snapper, Lutjanus griseus ......................................................................................................... 51 Pinfish, Lagodon rhomboides ............................................................................................................. 55 Sheepshead, Archosargus probatocephalus ..................................................................................... 61 i Spotted Seatrout, Cynoscion nebulosus ............................................................................................ 65 Striped Mullet, Mugil cephalus ........................................................................................................... 69 Nekton Community Structure ................................................................................................................. 73 Mercury Content Analysis ...................................................................................................................... 95 Ladyfish, Elops saurus ....................................................................................................................... 97 Common Snook, Centropomus undecimalis ...................................................................................... 99 Gag, Mycteroperca microlepis .......................................................................................................... 101 Gray Snapper, Lutjanus griseus ....................................................................................................... 103 Sheepshead, Archosargus probatocephalus ................................................................................... 105 Spotted Seatrout, Cynoscion nebulosus .......................................................................................... 107 Black Drum, Pogonias cromis .......................................................................................................... 109 Red Drum, Sciaenops ocellatus ....................................................................................................... 111 Gulf Flounder, Paralichthys albigutta ............................................................................................... 113 CONCLUSIONS ........................................................................................................................................ 115 Physiochemical conditions ................................................................................................................... 115 Composition of overall nekton community ........................................................................................... 115 Nekton Community Structure ............................................................................................................... 116 Mercury Content Analysis .................................................................................................................... 117 LITERATURE CITED ................................................................................................................................ 119 APPENDICES ........................................................................................................................................... 127 Appendix A. Animals designated as Selected Taxa because of their commercial or recreational importance. .................................................................................................................................. 129 Appendix B. Summary of species collected, by sampling event (bi-monthly), during Sarasota Bay nekton sampling, June 2012 to April 2013 ................................................................................... 131 Appendix C. Summary of species collected, by gear and stratum, during Sarasota Bay nekton sampling, June 2012 to April 2013 ............................................................................................... 135 Appendix D. Summary of species collected, by embayment, during Sarasota Bay stratified- random sampling, June 2012 to April 2013 ................................................................................. 139 Appendix E. Catch summary for taxa collected during three years, June 2009 to April 2013, of nekton sampling in Sarasota Bay with 21.3-m seines ................................................................. 143 Appendix F. Catch summary for taxa collected during three years, June 2009 to April 2013, of nekton sampling in Sarasota Bay with 183-m haul seines .......................................................... 147 Appendix G. Catch summary for taxa collected during three years, June 2009 to April 2013, of nekton sampling in Sarasota Bay with 6.1-m otter trawls ............................................................ 151 Appendix H. Species overview plots for dominant taxa (≥200 animals collected and ≥10 occurrence in a gear type) collected in 21.3-m shoreline seines