Results of the 3M Cod MSE

Abstract

The general objective of the 3M Cod MSE is to maintain the SSB of this species in the safe zone as defined by the NAFO precautionary approach framework and to assure the optimum utilization, rational management and conservation of the 3M cod stock. Based on this, five performance objectives were tested via five different Performance Statistics. Six different OMs and two HCRs with three different Ftarget were tested. The six OMs come from different assumptions over M and over the Stock-Recruitment relationship (SRR). The two HCRs are one model-based (based on the Bayesian XSA model approved by SC) and one model-free (based on the EU-FC survey). A 20% constraint of annual variation of TAC was set for both HCR. Based on this, a total of 24 scenarios were tested and results projected for the period 2014-2025. Differences in the results come mainly from the assumed stock recruitment relationship and in a much lesser extent of assumed M and the different Ftarget levels tested. The SSB have an increasing trend in all cases reaching a level well above Blim at the end of the projected period. There are two main trends in yields, one for the scenarios with the model-based HCR and other for the scenarios with the model-free HCR. In the first case, landings decrease to 6 500 tons in 2020, and after that increase until 2025 reaching a value between 10 500 and 15 000 tons, depending on the SRR assumed. In the case of the model-free HCR, until 2023 the decrease is very small and then a quiet constant value between 5 000 and 11 000 tons is reached. None of the tested HCR reached the established performance objectives in the 2016-2023 period but most of the scenarios met the performance objectives after 2024. The main reasons for not achieving these objectives are the high initial F and catch levels and the 20% catch constraint. The necessary period to achieve the performance objectives would be longer if we had applied a more restrictive TAC constraint (15% or 10%). If the TAC constraint is not applied, lower landings are allowed in the short-term period (2016-2020), but after that the increase in TAC is higher than if the constraint is applied.