HABITAT PREFERENCE OF THE DAGGERBLADE GRASS SHRIMP PALAEMONETES PUGIO AND WHETHER FIELD PREFERENCE IS CORRELATED WITH THE TREMATODE PARASITE MICROPHALLUS TURGIDUS by JESSYE SUE KIRKHAM A thesis submitted to the Graduate Faculty in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE IN MARINE SCIENCES SAVANNAH STATE UNIVERSITY May 2018 DEDICATION This thesis is dedicated to all those that believe in the power of science. To my mother, Samantha Stout, thank you for encouraging me to keep going even when I thought I couldn’t. Thank you to the rest of my family, especially Auntie Al and Uncle Jer, for listening to me talk about the “sea monkeys” and their parasites. To my thesis advisors Dr. Carla Curran and Dr. Michele Guidone, thank you for your continual patience and guidance, I know I was difficult at times but you kept pushing me to do my best. To my undergraduate advisor Dr. Matt Draud, you were the person that inspired me to study marine biology and the person that encouraged me to apply for graduate school. Thank you to those that always believed that I could do this, it wasn’t easy, but if it were then everyone would do it. 2 ACKNOWLEDGMENTS I would like to thank my thesis advisors Dr. Carla Curran and Dr. Michele Guidone for taking a chance on me and for helping me progress into a well-rounded young scientist. My committee member Dr. Sue Ebanks for providing her expertise in the subject matter and valuable feedback on my writing. I would like to thank the funding resources from previous years as it provided me with all the necessary equipment to conduct my research. If it weren’t for my amazing volunteers specifically: my friend and peer Lauren Lamboley, Shaiane Pinto, Jennie Wiggins, Sarah Webb, and all the trooper undergrads; Lieza Greenfield, Hannah Farmer, Sharifa Chandler, Shylyn Garcia, Ashley Dejesus, Kourtney Sizemore, Anita Thompson, many dolphin lab interns, and the undergrads at Armstrong State University, I would never have been able to do my field work each month. Special thanks to my former labmate Sarah Webb as she helped me find another passion in telemetry work and who has repeatedly helped me introduce myself to the science world. iv ABSTRACT Daggerblade grass shrimp Palaemonetes pugio reside in brackish estuarine systems and are thus exposed to the parasitic trematode Microphallus turgidus. The purpose of this study was to determine if the infection of P. pugio by M. turgidus was different across months and between two sites near Savannah, GA, and to determine habitat preference of infected P. pugio between the invasive red alga Gracilaria vermiculophylla and substrate-free open space in the laboratory. Trematode density was significantly higher in October-December 2016 and February 2017 (11.0-13.3) at one site and was significantly higher December 2016-January 2017 (10.1-10.3) and August- October 2017 (10.8-12.6) at the other site. In the laboratory, 76% of shrimp preferred tank edge locations whereas only 20% preferred G. vermiculophylla. Only 4% consistently selected the substrate-free open space. A wide range of factors such as food availability, presence of predators, interspecies competition, and abiotic conditions perhaps influence changes in parasite density and habitat preference. v TABLE OF CONTENTS DEDICATION ................................................................................................................... iii ACKNOWLEDGMENTS ................................................................................................. iv ABSTRACT .........................................................................................................................v TABLE OF CONTENTS ................................................................................................... vi LIST OF TABLES ........................................................................................................... viii LIST OF FIGURES ........................................................................................................... ix CHAPTER 1: Introduction and Overview ...........................................................................1 LITERATURE CITED ..........................................................................................16 CHAPTER 2: Monthly changes in the abundance, intensity, density, and prevalence of the microphallid trematode Microphallus turgidus and the haplosporidian hyperparasite Urosporidium crescens in the daggerblade grass shrimp Palaemonetes pugio and whether these parasites are correlated to where P. pugio is located in the environment ...................................................................................20 ABSTRACT ...........................................................................................................21 INTRODUCTION .................................................................................................22 MATERIALS AND METHODS ...........................................................................28 RESULTS ..............................................................................................................32 DISCUSSION ........................................................................................................43 LITERATURE CITED ..........................................................................................52 TABLES ................................................................................................................55 FIGURES ...............................................................................................................56 vi CHAPTER 3: Habitat preference of the daggerblade grass shrimp Palaemonetes pugio between the invasive red algae Gracilaria vermiculophylla and substrate- free open space in the laboratory .......................................................................................78 ABSTRACT ...........................................................................................................79 INTRODUCTION .................................................................................................80 MATERIALS AND METHODS ...........................................................................84 RESULTS ..............................................................................................................87 DISCUSSION ........................................................................................................90 LITERATURE CITED ..........................................................................................96 TABLES ................................................................................................................99 FIGURES .............................................................................................................101 LITERATURE CITED (THESIS) ...................................................................................109 APPENDICES .................................................................................................................116 APPENDIX A: FEEDING EXPERIMENTS ......................................................117 APPENDIX B: PILOT HABITAT PREFERENCE EXPERIMENTS ...............148 APPENDIX C: CURRICULUM VITAE ............................................................160 vii LIST OF TABLES Table 2.1. Prevalence of the daggerblade grass shrimp Palaemonetes pugio parasitized by the haplosporidian hyperparasite Urosporidium crescens De Turk at the Rodney J. Hall Boat Ramp (RJHBR) and the Frank Downing Fishing Pier (FDFP) near the Skidaway River in Savannah, Georgia from Fall 2016 through Fall 2017. Salinity and water temperatures were calculated as mean ± 1 SD ..........................55 Table 3.1. Experiments were conducted to determine the habitat preference of the daggerblade grass shrimp Palaemonetes pugio between the invasive red algae Gracilaria vermiculophylla and substrate-free open space in the laboratory. Shrimp were placed individually in 4 separate 33 cm X 20 cm X 23 cm substrate tanks and 4 separate substrate-free control tanks. All 8 shrimp were observed every min for 30 min during each trial to determine the preferred habitat of the shrimp ........................99 Table 3.2. The frequency and mean percentage (out of 1,440 observations) of the daggerblade grass shrimp Palaemonetes pugio was calculated to determine where P. pugio was located in treatment tanks. If shrimp were observed in multiple preferred locations, then those locations were excluded. Mean is calculated as percent of time. (GG=within Gracilaria vermiculophylla, GS=left section of the tank touching the edges, ES=right section of the tank touching the edges, GS+ES=combination of the edges). .................................................................................100 viii LIST OF FIGURES Figure 2.1. Map and location of the Rodney J. Hall Boat Ramp (RJHBR) and Frank Downing Fishing Pier (FDFP) sampling sites near the Skidaway River in Savannah, Georgia from October 2016 through December 2017 .......................................................56 Figure 2.2. Average length and + 1 SD of the daggerblade grass shrimp Palaemonetes pugio at A) the Rodney J. Hall Boat Ramp (RJHBR) and B) the Frank Downing Fishing Pier (FDFP) near the Skidaway River in Savannah, Georgia from October 2016 through December 2017. Letters represent significant differences across months ..................................................................................................57 Figure 2.3. Intensity (# of trematodes within