Spatial Variation in Fishery Exploitation of Mature Female Blue Crabs (C
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UNF Digital Commons UNF Graduate Theses and Dissertations Student Scholarship 2018 Spatial variation in fishery exploitation of mature female blue crabs (C. sapidus) in Chesapeake Bay Corey Travis Corrick University of North Florida Suggested Citation Corrick, Corey Travis, "Spatial variation in fishery exploitation of mature female blue crabs (C. sapidus) in Chesapeake Bay" (2018). UNF Graduate Theses and Dissertations. 798. https://digitalcommons.unf.edu/etd/798 This Master's Thesis is brought to you for free and open access by the Student Scholarship at UNF Digital Commons. It has been accepted for inclusion in UNF Graduate Theses and Dissertations by an authorized administrator of UNF Digital Commons. For more information, please contact Digital Projects. © 2018 All Rights Reserved Spatial variation in fishery exploitation of mature female blue crabs (C. sapidus) in Chesapeake Bay by Corey Travis Corrick A thesis submitted to the Department of Biology in partial fulfillment of the requirements for the degree of Master of Science, Biology UNIVERSITY OF NORTH FLORIDA COLLEGE OF ARTS AND SCIENCES April, 2018 Unpublished work © Corey Travis Corrick This Thesis titled “Spatial variation in fishery exploitation of mature female blue crabs (C. sapidus) in Chesapeake Bay” is approved: By the thesis committee: Date _________________________________________________ __________________ Dr. Eric G. Johnson Committee Chair _________________________________________________ __________________ Dr. Matthew B. Ogburn Committee Member _________________________________________________ __________________ Dr. Kelly Smith Committee Member Accepted for the Department of Biology: _________________________________________________ __________________ Dr. Cliff Ross Chair, Department of Biology Accepted for the College of Arts and Sciences: _________________________________________________ __________________ Dr. George Rainbolt Dean, College of Arts and Sciences Accepted for the University: _________________________________________________ __________________ Dr. John Kantner Dean, Graduate School ACKNOWLEDGEMENTS I would like to acknowledge my advisor, Eric Johnson, for giving me a number of opportunities over the last few years and taking a chance on a student with “gumption.” Thanks to the Smithsonian Environmental Research Center’s Fish & Invertebrate Lab, particularly Matt Ogburn, Rob Aguilar, Mike Goodison, Keira Heggie, Kim Richie, Midge Kramer, Tuck Hines, and numerous interns who assisted with field efforts, there’s no one else I’d rather get crabs with. Thanks to NOAA’s Saltonstall-Kennedy Grant Program for funding the project. Thanks to the UNF Coastal Biology program, that afforded me multiple opportunities throughout my undergraduate and graduate education. Lastly, thanks in large part to the many Chesapeake Bay fishers that participated in this study, it literally couldn’t have happened without you. iii TABLE OF CONTENTS ACKNOWLEDGEMENTS ........................................................................................................... iii LIST OF TABLES ......................................................................................................................... vi LIST OF FIGURES ...................................................................................................................... vii Abstract ........................................................................................................................................ viii Introduction ..................................................................................................................................... 1 Methods........................................................................................................................................... 5 Study sites ........................................................................................................................... 5 Collection & Tagging ......................................................................................................... 5 Reporting Rates & Exploitation .......................................................................................... 7 Spatial Analyses .................................................................................................................. 8 Individual Subestuaries ..................................................................................................... 10 Jurisdictional & Regional Exploitation ............................................................................. 10 Spawning Sanctuary Analyses .......................................................................................... 12 Results ........................................................................................................................................... 13 Spatial Analyses ................................................................................................................ 13 Seasonal Exploitation........................................................................................................ 14 Individual Subestuaries ..................................................................................................... 15 Jurisdictional & Regional Exploitation ............................................................................. 15 Spawning Sanctuary Analyses .......................................................................................... 16 iv Discussion ..................................................................................................................................... 16 Methodology ..................................................................................................................... 18 Spatial Analyses ................................................................................................................ 19 Seasonal Exploitation........................................................................................................ 20 Individual Subestuaries ..................................................................................................... 21 Jurisdictional & Regional Exploitation ............................................................................. 23 Spawning Sanctuary Analyses .......................................................................................... 25 Summary ........................................................................................................................... 26 References ..................................................................................................................................... 41 VITA ............................................................................................................................................. 46 v LIST OF TABLES Table 1. Chesapeake Bay subestuaries in which mature female blue crabs were tagged and released..........................................................................................................................................33 Table 2. Results of the large scale mark-recapture study conducted on mature female blue crabs in subestuaries of Chesapeake Bay in fall 2014 and summer 2015..............................................35 Table 3. Seasonal exploitation results of the large scale mark-recapture study conducted on mature female blue crabs in subestuaries of Chesapeake Bay in fall 2014 and summer 2015.....36 Table 4. Results of the large scale mark-recapture study conducted on mature female blue crabs in subestuaries of Chesapeake Bay in the fall 2014 split by region..............................................37 Table 5. The status of female blue crabs in Chesapeake Bay (CBSAC 2017).............................40 vi LIST OF FIGURES Figure 1. Chesapeake Bay subestuaries in which mature female blue crabs were tagged and released..........................................................................................................................................28 Figure 2. The tags used for the mark-recapture study of mature female blue crabs in Chesapeake Bay.................................................................................................................................................29 Figure 3. An adult female blue crab with an over-the-back, white vinyl tag...............................30 Figure 4. The jurisdictional split of the Potomac River (PRFC)..................................................31 Figure 5. The Virginia Blue Crab Sanctuary in lower Chesapeake Bay as mapped according to the Code of Virginia (4VAC20-752-10 et seq.)..................................................................................32 Figure 6. The recapture locations of mature female blue crabs released in 12 subestuaries and one coastal embayment of Chesapeake Bay in fall (September – October) 2014 and summer (July) 2015...............................................................................................................................................34 Figure 7. Breakdown of fishery capture of mature female blue crabs in Chesapeake Bay by management area...........................................................................................................................38 Figure 8. Spatial query of mature female blue crabs recaptured within the Virginia Blue Crab Sanctuary.......................................................................................................................................39 vii Abstract From 2008 to 2012, the total