Report of the North Sea Saithe Management Strategy Evaluation

A Management Strategy Evaluation (MSE) analysis was conducted for North Sea saithe (subarea IV, Division IIIa and subarea VI) in response to a joint EU–Norway request to ICES for an assessment on options to revise the long-term management plan for saithe in the North Sea. Population trajectories for North Sea saithe were ex-plored under five alternative management scenarios in conjunction with the potential for optimistic (high recruitment and growth) and pessimistic (low recruitment and growth) biological production. B-Adapt was used for the operating model, and XSA was used as the basis for the management model corresponding with the methodolo-gy used in the 2012 ICES WGNSSK working group report. Future population trajec-tories for North Sea saithe depend on the management options adopted as well as the level of incoming recruitment and growth. Results for 2020 indicate that although the current management plan yields a favourable trade-off between the risk of spawning stock biomass remaining above Blim and median catch under an optimistic biological production scenario, this trade-off deteriorates under a pessimistic biological produc-tion scenario. When just considering the probability of spawning stock biomass re-maining above Blim, the management options that use alternative TAC stability mechanisms achieve similar values to the current plan under an optimistic biological production scenario, but also perform slightly more favourably under a pessimistic biological production scenario.