Stock Assessment of Red Mullet, Mullus barbatus Linnaeus, 1758 by Length-based and Catch-based Models in the Northeastern Mediterranean

Abstract

Stock assessment for Mullus barbatus using catch-based (CMSY) and length based (LBB, LBSPR and LIME) data limited models were performed by using official catch statistics and commercial length frequency data from northeastern Mediterranean. The CMSY model results showed that the catch amount did not exceed MSY, and the fisheries reference points (B/BMSY and F/FMSY) indicated a healthy stock status in 2020. The LBB model results indicated that the biomass ratio was above safe biological limits (B<0.5 BMSY) but fishing mortality was slightly higher than natural mortality. Likewise, LBSPR results showed that SL50 for red mullet was higher than its Lm50, while the estimated median SPR was above the limit of 20% set as the biological reference point. The LIME results were more optimistic than those from the LBB and LBSPR and the estimated SPR was found above 40% which is the target reference point for a sustainable stock. According to the results of different assessment models, the red mullet stock was deemed sustainable in terms of biomass but observation of fishing pressure is required.