Bioeconomic multistock reference points as a tool for overcoming the drawbacks of the landing obligation

Abstract

The landing obligation policy was one of the major innovations introduced in the last Common Fisheries Policy reform in Europe. It is foreseen that the policy will affect the use of fishing opportunities and hence the economic performance of the fleets. The problem with fishing opportunities could be solved if single-stock total allowable catches (TACs) could be achieved simultaneously for all the stocks. In this study, we evaluate the economic impact of the landing obligation policy on the Spanish demersal fleet operating in the Iberian Sea region. To generate TAC advice, we used two sets of maximum sustainable yield (MSY) reference points, the single-stock MSY reference points defined by ICES and a set of multistock reference points calculated simultaneously using a bioeconomic optimization model. We found that the impact of the landing obligation is time and fleet dependent and highly influenced by assumptions about fleet dynamics. At fishery level, multistock reference points mitigate the decrease in the net present value generated by the implementation of the landing obligation. However at fleet level, the effect depends on the fleet itself and the period. To ensure the optimum use of fishing opportunities, the landing obligation should be accompanied by a management system that guarantees consistency between single-stock TACs. In this regard, multistock reference points represent an improvement over those currently in use. However, further investigation is necessary to enhance performance both at fleet level and in the long term.

Integrated ecological–economic fisheries models—Evaluation, review and challenges for implementation

“…Also for this table, the compiled material is shown in the spider web summary plots in the results section in Figures Table S3, further details and descriptions of the different categories in the matrix table are provided. Garcia, Santurtun, Prellezo, Sanchez, & Andres, 2012;Garcia, Urtizberra, Diez, Gil, & Marchal, 2013;García, Prellezo, et al, 2016;García, Sanchez, Prellezo, Urtizberea, Andres 2016;Jardim et al, 2013;Prellezo et al, 2016. 26 FCUBE ICES 2006, 2014aHoff et al, 2010;Ulrich et al, 2011Ulrich et al, , 2017Iriondo et al, 2012;Maravelias, Damalas, Ulrich, Katsanevakis, & Hoff, 2012;Jardim et al, 2013;EU STECF, 2015b;ICES 2015c,d.…”

Robust combination of the Morris and Sobol methods in complex multidimensional models

“…As no abundance estimate for any of these stocks exists, it has been assumed that the catch is a function of the metier's effort and independent of biomass. A brief description of the submodels used to describe the processes that constitute this specific implementation of FLBEIA is given in Table 1. A detailed description of the case study appears in Garcia et al (2017a). Table A.5 in Appendix A shows a description of the K = 133 input factors of the model.…”

“…The values of maturity and retention curves have been simulated using a beta distribution and effort share and aging error using a Dirichlet distribution. The parameters of the distributions have been obtained constraining the mean to the value in Garcia et al (2017a) and the coefficient of variation (CV) to a 30%. In the case of multiplicative observation errors, that are not included in Garcia et al (2017a), a mean equal to one has been used, i.e, the errors are unbiased.…”

“…The parameters of the distributions have been obtained constraining the mean to the value in Garcia et al (2017a) and the coefficient of variation (CV) to a 30%. In the case of multiplicative observation errors, that are not included in Garcia et al (2017a), a mean equal to one has been used, i.e, the errors are unbiased. The aging error has been modeled using a square matrix in which elements a il describe the probability of assigning age i to a fish of age l, and corresponds to the expected value of the Dirichlet distribution.…”

The bad, the good and the very good of the landing obligation implementation in the Bay of Biscay: A case study of Basque trawlers

“…Simulations have been performed using FLBEIA (Garcia et al, 2013) (García et al, 2016;Jardim et al, 2013). This is a simulation bioeconomic model coupled in all its dimensions (economic, biologic and social).…”