Pink shrimp assessment modeling update from a static VPA to an integrated assessment model Stock Synthesis

Southeast Fisheries Science Center (U.S.), Galveston Laboratory,

"The Gulf of Mexico (GOM) pink shrimp stocks were deemed undergoing overfishing in 2008 at the conclusion of the 2007 fishing season (National Marine Fisheries Service 2009). This designation was made because the SEFSC, Galveston Laboratory's Virtual Population Analysis (VPA) results indicated the 2007 pink shrimp spawning stocks, i.e., the number of parents, fell below the overfishing limit. However, because other fishery indicators, e.g., catch per unit effort (CPUE), did not corroborate this finding, SEFSC staff recommended maintaining the current stock status designation until the VPA model could be thoroughly reviewed to determine if it is accurately modeling the GOM pink shrimp population's behavior, and hence, if this designation should be supported ... To date we have developed a preliminary model in Stock Synthesis, and have made several modeling runs incorporating commercial pink shrimp data from 1960 - 2008. This report is intended as a template to document and outline the steps taken to update the SEFSC shrimp stock assessment models"--Introduction, paragraph 1.

Technical Memorandum