Effectiveness: Precautionary Approach
6. There has been little sign of improvement in the state of the west of Scotland cod stocks in recent years.
7. As with many area closures of this type, it is challenging to substantiate its precise biological effect. One school of thought is that, since the stock has yet to show significant signs of recovery, it is imperative that the protection offered by the closure, to date, is maintained or even strengthened, because the stock remains vulnerable; on the other hand, some have argued that the closure is not having a demonstrable effect and should therefore be amended or discontinued.
8. The proposed closure area in the Clyde is within ICES Area 6a (West of Scotland)4 which in 2021 has a bycatch total allowable catch (TAC) of 1279 tonnes for cod and a 2% bycatch limit. The latest scientific advice from ICES for cod in Area 6a states that recruitment of cod has been low since 2001 and that, when the maximum sustainable yield (MSY) approach is applied, there should be zero catches in each of the years 2021 and 2022.
9. In August 2015 a scientific paper entitled "Evaluating the effectiveness of a seasonal spawning area closure"  was published in the ICES Journal of Marine Science, focusing on this particular closure area. The results from the study was that whilst the rationale for the spawning closure was sensible, it had no detectable impact on wider cod numbers in the Clyde. The paper concluded that this was probably due to the poor state of the stock when the closure was implemented and the continuing sources of mortality.
10. This paper noted, based on earlier studies, that cod from the Clyde are reproductively isolated, having little detectable exchange with the northern spawning aggregations,. Genetic evidence also supports this finding, as Clyde cod were found to have a greater similarity to those from the Irish Sea than the cod from the northern aggregations. Irish Sea cod (ICES Area 7a) is also in poor state, with ICES advising catches of no more than 74 tonnes under the precautionary approach. Given the evidence for reproductive isolation it is even more important to have specific management measures in place in the Clyde.
11. More recently, a study was undertaken by the Scottish Oceans Institute and Clyde Fishermen's Association (CFA) during the spawning period with demersal and pelagic gears. A final version of the report can be requested from the CFA. Early results from the study show the presence of spawning cod in the closed area during the closure period, indicating that the closure is in the right place at the right time.
12. Taking all of the available evidence into account, the Scottish Government remains of the view that the closure offers some necessary protection to spawning cod at a crucial stage in their life cycle. To remove closure provisions altogether would place cod stocks at unacceptable risk of further depletion, unless appropriate alternative measures were introduced in their place.