North Sea Greater Silver Smelt Fisheries Management Plan

Stock Assessment and MSY

Scientific evidence

As set out in Section 3.2 of the JFS, the UK takes an evidence-based approach to fisheries management, making use of the best available scientific evidence. For the purpose of fisheries management and setting catch limits (Total Allowable Catch (TAC) setting), this tends to focus on the use of advice produced by ICES, although other sources of information, including data from the fishing industry, may also be used.

ICES provides biennial advice for GSS in the Northeast Arctic, North Sea, Skagerrak and Kattegatt. ICES advice is organised according to categories, ranging from 1 (the most information available) to 6 (the least). The stock is now an ICES Category 2 stock with the new assessment method (SPiCT) considered a marked improvement compared to the previously used ICES trend-based advice rule. The acoustic survey providing the biomass index is conducted every second year. Hence, advice is given biennially.

Benchmark exercises are a process used by ICES to evaluate existing and new scientific evidence and methods and, where relevant, apply them in the stock assessment process. They are part of the continuous improvement process which ensures that ICES advice is based on the best available scientific evidence. ICES completed an assessment benchmarking process for GSS in the Northeast Arctic, North Sea, Skagerrak and Kattegatt in 2024.

Assessment of evidence

The following evidence has been collated from the most recent ICES advice sheet (ICES 2026)^[7]. ICES advice indicates that current fishing pressure on the stock is below F_MSY and F_lim, and the stock size is above MSY B_trigger.

ICES advice for GSS is given biennially for North Sea GSS. GSS is an ICES Category 2 stock with the new assessment method (SPiCT). However, due to high uncertainty in the survey index used in the assessment, ICES recommends using the lower catch percentile (i.e. 15th percentile) than in the standard ICES rule.