Project

Plaice banking and Borrowing

This project used management strategy evaluation (MSE) to evaluate the likely effects of inter-annual quota flexibility on the effectiveness of the North Sea flatfish management plan. IMARES and subsequently ICES have evaluated the ±10% inter-annual quota flexibility scheme for plaice in the context of the plaice and sole management plan.

Different scenarios showed that adding the inter-annual quota flexibility did not substantially increase the probability of SSB falling below Blim, compared to scenarios without inter-annual quota flexibility. Average yield did not change substantially either. It was therefore concluded that the multiannual management plan is robust to inclusion of inter-annual quota flexibility in terms of the probability of the stock biomass falling below Blim, and without substantial changes in average yield. This conclusion is conditional on the inter-annual quota flexibility being suspended when the stock is estimated to be outside safe biological limits.

An ICES (International Council for the Exploration of the Sea) advice in response to the EU request was published in June 2013. It can be found at ICES: http://www.ices.dk/sites/pub/Publication%20Reports/Advice/2013/Special%20requests/EU_Inter-annual_quota_flexibility_Plaice.pdf. 

A full report on the results of the evaluation is available from ICES secretariat: "Brunel, T., and Miller, D. C. M.. 2013. An Evaluation of the Impact of Interannual Quota Flexibility (Banking and Borrowing) on the Performance of the North Sea Flatfish Long-Term Management Plan. ICES CM 2013/ACOM:64".