Updated Blacktip Shark Abundance Indices from NMFS Bottom Longline Surveys in the Northern Gulf of Mexico

The Southeast Fisheries Science Center Mississippi Laboratories (MSLABS) has conducted standardized bottom longline surveys in the Gulf of Mexico, Caribbean, and U.S. South Atlantic Ocean since 1995. In addition to the annual survey, in 2011, the Congressional Supplemental Sampling Program (CSSP) was conducted, where high levels of standardized bottom longline survey effort were maintained from April through October. During the benchmark assessment for Blacktip Sharks, data from the MSLABS Bottom Longline Survey and the CSSP Survey were used to produce a relative abundance index for Blacktip Shark. This document serves as an update to the index that was used in the previous assessment.