EU/Norway request to ICES for a revision of the Long-Term Management Strategy for northern shrimp (Pandalus borealis) in divisions 3.a and 4.a East (Skagerrak and Kattegat and northern North Sea in the Norwegian Deep)

 ICES has evaluated a 12-month TAC with a TAC-year of 1 July–30 June for northern shrimp in divisions 3.a and 4.a East. During this evaluation, the model year was shifted to start on 1 July, and numerous harvest control rules (HCRs) with different combinations of MSY Btrigger and Ftarget were assessed. 

ICES advises that a new 12-month TAC with a TAC-year of 1 July–30 June can be considered appropriate for the management of fisheries on this stock, subject to the amendment of the MSY Btrigger value.

It was found that the current HCR for this stock, Ftarget = FB30% (i.e. the F that brings the stock to 30% of an unfished biomass B0) and MSY Btrigger = 80% x B30, no longer meets the criteria of the long-term management strategy, as it has a greater than 5% probability of the spawning-stock biomass (SSB) falling below Blim in several years of the simulated period. An alternative HCR with MSY Btrigger set at 90% x B30 was found to meet all three criteria of the long-term management strategy. The proposed HCR results in the median long-term yield being 97% of the deterministic maximum sustainable yield, and Ftarget remains at FB30%. 

Two additional TAC-year options were requested by EU/Norway (starting in April and May, respectively). However, as agreed by all parties, these options were not evaluated by ICES. The banking and borrowing aspect of the request requires further methodology development and will be conducted by ICES in Q3 of 2023.