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Horseshoe Crab Stock Assessment for Peer Review

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Horseshoe Crab Stock Assessment for Peer Review Stock Assessment Report No. 09-02 (Supplement A) of the Atlantic States Marine Fisheries Commission Horseshoe Crab Stock Assessment for Peer Review November 2009 Healthy, self-sustaining populations for all Atlantic coast fish species or successful restoration well in progress by 2015 Stock Assessment Report No. 09-02 (Supplement A) of the Atlantic States Marine Fisheries Commission Horseshoe Crab Stock Assessment for Peer Review Prepared by the ASMFC Horseshoe Crab Stock Assessment Subcommittee Dr. Dave Smith (Chair), U.S. Geological Survey Mr. Jeff Brust, New Jersey Division of Fish and Wildlife Dr. Michelle Davis, Virginia Polytechnic Institute and State University (Virginia Tech) Mr. John Maniscalco, New York State Department Environmental Conservation, Bureau of Marine Resources Mr. Stew Michels, Delaware Division of Fish and Wildlife Mr. John Sweka, U.S. Fish & Wildlife Service With special assistance from Mr. Rich Wong, Delaware Division of Fish and Wildlife Accepted by the Horseshoe Crab Management Board on February 3, 2010 A publication of the Atlantic States Marine Fisheries Commission pursuant to National Oceanic and Atmospheric Administration Award No. NA05NMF4741025 Table of Contents Preface .......................................................................................................................................... vii Terms of Reference for the Horseshoe Crab Stock Assessment ............................................ viii 1.0 Introduction ............................................................................................................................. 1 1.1 Brief Overview and History of Fisheries .............................................................................. 1 1.1.1 Bait Fishery .................................................................................................................... 2 1.1.2 Biomedical Fishery ........................................................................................................ 2 1.2 Management Unit Definition ................................................................................................ 3 1.3 Regulatory History ................................................................................................................ 3 1.4 Assessment History ............................................................................................................... 4 2.0 Life History .............................................................................................................................. 4 2.1 Stock Definitions .................................................................................................................. 4 2.1.1 Genetics.......................................................................................................................... 5 2.1.2 Morphometric Information ............................................................................................ 6 2.2 Migration Patterns ................................................................................................................. 6 2.3 Age ........................................................................................................................................ 7 2.4 Growth .................................................................................................................................. 7 2.5 Reproduction ......................................................................................................................... 8 2.6 Natural Mortality .................................................................................................................. 9 2.7 Sex Ratio ............................................................................................................................... 9 3.0 Habitat Description ............................................................................................................... 10 3.1 Brief Overview Habitat Requirements ............................................................................... 10 3.1.1 Spawning, Egg, and Larval Habitat ............................................................................. 10 3.1.2 Juvenile and Adult Habitats ......................................................................................... 12 4.0 Fishery Dependent Data Sources ......................................................................................... 14 4.1 Commercial Bait Fishery .................................................................................................... 14 4.1.1 Data Collection and Treatment .................................................................................... 14 4.1.2 Commercial Bait Landings .......................................................................................... 15 4.1.3 Commercial Bait Discards/Bycatch ............................................................................. 16 4.1.4 Commercial Bait Catch Rates (CPUE) ........................................................................ 16 4.1.5 Commercial Bait Prosomal Widths ............................................................................. 16 4.1.6 Potential biases, Uncertainty, and Measures of Precision ........................................... 17 4.2 Commercial Biomedical Fishery ........................................................................................ 18 4.3 Recreational ........................................................................................................................ 19 5.0 Fishery-Independent Data.................................................................................................... 19 6.0 Methods .................................................................................................................................. 19 6.1 Background ......................................................................................................................... 20 6.1.1 Regional Trend Analyses ............................................................................................. 20 6.1.2 Autoregressive Integrative Moving Average Description ........................................... 20 6.1.3 Surplus Production Model Description ........................................................................ 21 6.1.4 Catch Survey Analysis Description ............................................................................. 22 6.2 Configuration ...................................................................................................................... 22 6.2.1 Regional Trend Analyses ............................................................................................. 22 6.2.2 Autoregressive Integrative Moving Average ............................................................... 22 6.2.3 Surplus Production Model ........................................................................................... 22 ii 6.2.4 Catch Survey Analysis ................................................................................................. 23 7.0 Results .................................................................................................................................... 23 7.1 Regional Trend Analysis .................................................................................................... 23 7.2 Autoregressive Integrative Moving Average ...................................................................... 23 7.3 Surplus Production Model .................................................................................................. 24 7.3.1 Goodness of Fit ............................................................................................................ 24 7.3.2 Parameter Estimates ..................................................................................................... 25 7.3.5 Projection Estimates ..................................................................................................... 25 7.4 Catch Survey Analysis ........................................................................................................ 25 8.0 Stock Status ........................................................................................................................... 25 8.1 Current Overfishing, Overfished/Depleted Definitions ...................................................... 25 8.2 Stock Status Determination ................................................................................................ 25 9.0 Research Recommendations ................................................................................................ 27 10.0 Literature Cited .................................................................................................................. 28 11.0 Tables ................................................................................................................................... 38 12.0 Figures .................................................................................................................................. 57 Appendix A .................................................................................................................................. 79 Appendix B .................................................................................................................................. 80 iii List of Tables Table 1. Reported Atlantic coast horseshoe crab landings and value, 1970 – 2008 (NMFS) Commercial Fishery Landings Database 2009) ..........................................................
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