Juvenile Population Dynamics of Families Lutjanidae and Serranidae in the Gulf of Mexico, with Respect to the Loop Current and other Hydrographic Features by Sebastian Velez A Thesis Submitted to the Faculty of The Charles E. Schmidt College of Science In Partial Fulfillment of the Requirements for the Degree of Master of Science Florida Atlantic University Boca Raton, FL May 2018 Copyright 2018 by Sebastian Velez ii Acknowledgements Funding for this project was provided by the Gulf of Mexico Research Initiative and the DEEPEND Consortium. I am very grateful to Dr. Tracey Sutton and April Cook of Nova Southeastern University for their guidance, and assistance with data management for this project. April’s help with this process was crucial to our project’s success. I was very fortunate to have been a member of the DEEPEND Consortium and am thankful for all the experiences and friends I have collected as a result of my involvement. I am also thankful for the constant support and networking experience I received from my fellow lab-mates Amanda Hipps, Richard Jones, and Carolyn Hanish. I’m thankful to my family for their unfaltering faith in my abilities. Lastly, I am grateful to Dr. Jon Moore for his support, technical assistance, laboratory space, guidance, and friendship. iv Abstract Author: Sebastian Velez Title: Juvenile Population Dynamics of Families Lutjanidae and Serranidae in the Gulf of Mexico, with Respect to the Loop Current and other Hydrographic Features Institution: Florida Atlantic University Thesis Advisor: Dr. Jon A. Moore Degree: Master of Science Year: 2018 The Gulf of Mexico (GoM) contains a variety oceanographic features including; the Loop Current, cyclonic/anticyclonic eddies, common water, and the Mississippi River Plume. The relationship these features have on the community assemblages of Families Lutjanidae and Serranidae has been of great interest from both biological and economic standpoints. These families represent some of the most economically important fisheries in the GoM. Identifying the role these features play in the transportation of larval and juvenile nearshore species to offshore environments is vital to resource managers. Using data collected shortly after the Deepwater Horizon Oil Spill via the NOAA Natural Resource Damage Assessment in 2011 as well as cruises conducted by the Deep Pelagic Nekton Dynamics of the Gulf of Mexico (DEEPEND) Consortium from 2015-2017, the faunal composition and abundance of these families were analyzed with respect to seasonality, oceanographic features, depth distribution, and time. v Dedication This manuscript is dedicated to my loving family, for supporting me. I would like to dedicate this work especially to my father, Jorge Ivan Velez, whose original love for the oceans and the animals therein inspired me to devote my life to this field of study. Lastly, to my mother for her undying support, love for her children, and all their dreams. Juvenile Population Dynamics of Families Lutjanidae and Serranidae in the Gulf of Mexico, with Respect to the Loop Current and other Hydrographic Features List of Tables ..................................................................................................................... ix List of Figures .................................................................................................................... xi Chapter One: Introduction .................................................................................................. 1 Family Lutjanidae ........................................................................................................... 3 Family Serranidae ........................................................................................................... 5 Economic Importance ..................................................................................................... 8 Management .................................................................................................................. 10 Ichthyoplankton ............................................................................................................. 14 Chapter Two: Project Description and Background ......................................................... 21 Statement of Objectives and Hypotheses: ..................................................................... 23 Purpose ...................................................................................................................... 23 Goals .......................................................................................................................... 23 Hypotheses................................................................................................................. 24 Materials and Methods .................................................................................................. 24 Description of Study Areas ........................................................................................ 24 Sampling and Sampling Process................................................................................ 31 Laboratory Procedures and Taxonomic Identification .................................................. 36 vii Statistical and Data Analyses .................................................................................... 37 Chapter Three: Results ...................................................................................................... 40 R/V Pisces ...................................................................................................................... 40 M/V Meg Skansi ............................................................................................................ 50 DEEPEND ................................................................................................................. 64 DEEPEND and M/V Meg Skansi ............................................................................... 71 Chapter Four: Discussion .................................................................................................. 83 Future Directions ........................................................................................................... 96 Appendix ......................................................................................................................... 101 References ....................................................................................................................... 128 viii List of Tables Table 1. Sampling depths for each specific net of the MOCNESS apparatus for the DEEPEND and NOAA ONSAP Research Cruises (Sutton et al. 2015a). ............ 34 Table 2. Faunal composition and abundance of family Serranidae from the R/V Pisces and the IH Trawl sampling gear.................................................................................. 41 Table 3. Faunal composition and abundance of family Lutjanidae from the R/V Pisces and the IH Trawl sampling gear. .............................................................. 41 Table 4. Faunal composition and standardized density (No.x10-6m-3) measurements of families Serranidae and Lutjanidae across the fall, spring, summer, and winter seasons from the R/V Pisces Cruises. .............................................................. 45 Table 5. Number of measured individuals (n) per lowest taxonomic identification, their size ranges, and the mean standard length (SL) for the R/V Pisces. ................... 48 Table 6. Faunal composition and abundance of family Serranidae from the M/V Meg Skansi and the MOCNESS sampling gear. ................................................. 51 Table 7. Faunal composition and abundance of family Lutjanidae from the M/V Meg Skansi and the MOCNESS sampling gear. ................................................. 52 Table 8. Faunal composition and standardized density (No.x10-6m-3) measurements of families Serranidae and Lutjanidae across the spring, summer and winter seasons from the M/V Meg Skansi Cruises ................................................................. 56 Table 9. Number of measured individuals (n) per lowest taxonomic identification, their size ranges, and the mean standard length (SL) for the M/V Meg Skansi. ......... 63 ix Table 10. Faunal composition and abundance of family Serranidae from the DEEPEND Research Cruises and the MOCNESS sampling gear.............................. 66 Table 11. Faunal composition and abundance of family Lutjanidae from the DEEPEND Research Cruises and the MOCNESS sampling gear.............................. 66 Table 12. Faunal composition and standardized density (No.x10-6m-3) measurements of families Serranidae and Lutjanidae across the spring and summer seasons from DEEPEND Cruises (1-5). ........................................................................................... 70 Table 13. Number of measured individuals (n) per lowest taxonomic identification, their size ranges, and the mean standard length (SL) for the DEEPEND cruise series. ................................................................................................................ 70 Table 14. Number of individuals (n) per lowest taxonomic identification, standardized densities (No.x10-6m-3), size ranges, and mean standard length (mm), by depth bin for the DEEPEND and M/V Meg Skansi cruise series. ............................... 73 x List of Figures Figure 1. SEAMAP/NRDA Station Grid. ......................................................................... 26 Figure 2. Cruise track for DEEPEND Cruise 1, May 1-May