Report of the Gulf of Mexico SSC Review of the SEDAR 52 Red Snapper Assessment

Dr. Matt Smith and Dr. Dan Goethel (SEFSC) presented the SEDAR 52 stock assessment results for Gulf of Mexico red snapper. The assessment process was delayed at key points due to data deadlines which were not met. SEDAR 52 was a standard assessment, which utilized the agreed upon model parametrizations and data inputs from the SEDAR 31 benchmark assessment (and the 2014 Update of the SEDAR 31 benchmark). Data inputs were updated through 2016. New data and minor model changes were explored per the TORs developed through the SEDAR process.

Life history parameters were largely unchanged from the 2014 SEDAR 31 update assessment. Additional samples were added to the age and length composition data, which were used in fleet specific age-length keys in the assessment. Based on recent studies, the discard mortality rate for the recreational fleets was increased from 10% to 11.8%.

The method for estimating discard fractions for the recreational headboat and commercial longline and handline fisheries was improved to produce more realistic estimates based on SEDAR best practices and recommendations by the data providers (and approved by the SEDAR 52 panel). The MRIP discard estimates matched up well with the previous assessment. It was noted that there were differences between Louisiana-specific private recreational discard estimates, and those estimated by LA Creel. The SEFSC staff clarified that the SEDAR 52 method did not parse data apart by state, but rather extrapolated discard data Gulf-wide. The method for estimating discard fractions for the recreational headboat and commercial longline and handline fisheries was improved to produce more realistic estimates based on SEDAR best practices and recommendations by the data providers (and approved by the SEDAR 52 panel). The MRIP discard estimates matched up well with the previous assessment. It was noted that there were differences between Louisiana-specific private recreational discard estimates, and those estimated by LA Creel. The SEFSC staff clarified that the SEDAR 52 method did not parse data apart by state, but rather extrapolated discard data Gulf-wide.

Catch-per-unit-effort (CPUE) indices for the commercial handline fleets were truncated in 2006 (per the SEDAR 31 benchmark assessment methods) to exclude IFQ years. A missed management regulation was discovered in the CPUE standardization code for the MRFSS index in the eastern Gulf and was fixed resulting a slight change in trend (from declining to steady) for the last few years; the same data for the western Gulf were unchanged. No change was observed after updating the headboat CPUE data either.