An Age-, Sex-And Spatially-Structured Stock Assessment of the Indian Ocean Swordfish Fishery 1950-2012, Using Stock Synthesis (original) (raw)

An Indian Ocean swordfish (Xiphias gladius) stock assessment using Stock Synthesis 3 (SS3) software is described. The approach uses a highly disaggregated model to integrate several sources of fisheries data and biological research into a unified framework. The model used is updated from the analysis conducted in 2011. Rather than use a fairly complex grid as used in 2011, the model examined this year key uncertainties, namely growth, natural mortality, steepness and weighting of the length composition data as opposed to the CPUE survey data (2 growth curves with 2 natural mortality vectors that correspond to the growth curves from a biological basis (total of 2 choices), 3 steepness values, and two weighting alternatives of data, and examining once CPUE series scenario that is equally weighted across all series, and one that only examines the Japanese CPUE series, with the EU fleets representing the SW Region). The implications of 10 years of projections over a ranged of constant c...