Status of Greenspotted Rockfish, Sebastes Chlorostictus, in U.S. Waters Off California
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Status of Greenspotted Rockfish, Sebastes chlorostictus, in U.S. waters off California Photo: Rick Starr E.J. Dick*, Don Pearson, and Steve Ralston Fisheries Ecology Division Southwest Fisheries Science Center National Marine Fisheries Service *corresponding author; [email protected] Table of Contents Executive Summary .................................................................................................................................................................. i Stock ........................................................................................................................................................................................... i Catches ...................................................................................................................................................................................... i Data and assessment ........................................................................................................................................................ iii Stock biomass ...................................................................................................................................................................... iii Recruitment ......................................................................................................................................................................... vi Exploitation status ........................................................................................................................................................... vii Reference points ................................................................................................................................................................ ix Management performance ............................................................................................................................................. xi Unresolved problems and major uncertainties .................................................................................................... xi Decision tables ................................................................................................................................................................... xii Research and data needs .............................................................................................................................................. xvi 1. Introduction .......................................................................................................................................................................... 1 1.1 Distribution and Stock Structure .......................................................................................................................... 1 1.2 Life History and Ecosystem Interactions ........................................................................................................... 1 1.3 Historical and Current Fisheries ........................................................................................................................... 3 1.4 Management History and Performance ............................................................................................................. 4 1.5 Fisheries in Mexico ..................................................................................................................................................... 5 2. Data ........................................................................................................................................................................................... 5 2.1 Data from Commercial Fisheries .......................................................................................................................... 5 2.1.1 Recent Commercial Landings (1969-2010) ............................................................................................. 5 2.1.2 Historical Commercial Catch Reconstruction ......................................................................................... 6 2.1.3 Discards in Commercial Fisheries ................................................................................................................ 7 2.1.4 Foreign Catch ........................................................................................................................................................ 8 2.1.5 Biological Sampling of Commercial Fisheries ......................................................................................... 8 2.2 Data from Recreational Fisheries ....................................................................................................................... 10 2.2.1 Recent Recreational Landings (1980 to present) ................................................................................ 10 2.2.2 Historical Recreational Catch Reconstruction ...................................................................................... 10 2.2.3 Discards in Recreational Fisheries ............................................................................................................ 11 2.2.4 Biological Sampling of Recreational Fisheries ...................................................................................... 11 2.2.5 CDFG Onboard Observer Index for Northern California, 1987-1998 ......................................... 13 2.2.6 RecFIN CPUE Indices for Northern and Southern California .......................................................... 13 2.3 Fishery Independent Data ..................................................................................................................................... 14 2.3.1 Northwest Fisheries Science Center (NWFSC) combined trawl survey .................................... 14 2.3.2 Southern California Hook-and-Line Survey ........................................................................................... 14 2.3.3 Fishery-independent data considered but not used .......................................................................... 15 2.4 Biological Data ............................................................................................................................................................ 15 2.4.1 Length at Age ...................................................................................................................................................... 16 2.4.2 Validation of Age Estimates .......................................................................................................................... 16 2.4.3 Ageing Precision and Bias ............................................................................................................................. 17 2.4.4 Weight-Length Relationship ........................................................................................................................ 17 2.4.5 Natural Mortality .............................................................................................................................................. 17 2.4.6 Maturity and Fecundity .................................................................................................................................. 18 2.4.7 Sex Ratios ............................................................................................................................................................. 18 3. Model Description ............................................................................................................................................................ 18 3.1 History of Modeling Approaches ........................................................................................................................ 18 3.2 Assessment Program ............................................................................................................................................... 19 3.3 Areas and Fleets ......................................................................................................................................................... 19 3.4 Model specification and parameters ................................................................................................................. 20 3.5 Stock and recruitment ............................................................................................................................................. 21 4. Model selection and evaluation .................................................................................................................................. 21 4.1 Alternative models, structural choices, and key assumptions ............................................................... 21 4.1.1 Alternative hypotheses for changes in length frequency data ....................................................... 21 4.1.2 Requests by the STAR Panel and responses by the Stock Assessment Team (STAT) .......... 22 4.2 Base case model results .......................................................................................................................................... 27 4.2.1 Northern California base model ................................................................................................................. 28 4.2.2 Southern California base model .................................................................................................................. 29 4.3 Uncertainty and sensitivity analyses ................................................................................................................ 30