http://hdl.handle.net/20.500.12627/189 2026-05-01T04:58:49Z http://hdl.handle.net/20.500.12627/1001 Status and rebuilding of European fisheries Matz-Lueck, Nele; Tsikliras, Athanassios C.; Demirel, Nazli; Dimarchopoulou, Donna; Froese, Rainer; Winker, Henning; Coro, Gianpaolo; Scarcella, Giuseppe Since January 2014, the reformed Common Fisheries Policy (CFP) of the European Union is legally binding for all Member States. It prescribes the end of overfishing and the rebuilding of all stocks above levels that can produce maximum sustainable yields (MSY). This study examines the current status, exploitation pattern, required time for rebuilding, future catch, and future profitability for 397 European stocks. Fishing pressure and biomass were estimated from 2000 to the last year with available data in 10 European ecoregions and 2 wide ranging regions. In the last year with available data, 69% of the 397 stocks were subject to ongoing overfishing and 51% of the stocks were outside of safe biological limits. Only 12% of the stocks fulfilled the prescriptions of the CFP. Fishing pressure has decreased since 2000 in some ecoregions but not in others. Barents Sea and Norwegian Sea have the highest percentage (> 60%) of sustainably exploited stocks that are capable of producing MSY. In contrast, in the Mediterranean Sea, fewer than 20% of the stocks are exploited sustainably. Overfishing is still widespread in European waters and current management, which aims at maximum sustainable exploitation, is unable to rebuild the depleted stocks and results in poor profitability. This study examines four future exploitation scenarios that are compatible with the CFP. It finds that exploitation levels of 50-80% of the maximum will rebuild stocks and lead to higher catches than currently obtained, with substantially higher profits for the fishers. 2018-01-01T00:00:00Z http://hdl.handle.net/20.500.12627/997 http://hdl.handle.net/20.500.12627/999 On the pile-up effect and priors for L-inf and M/K: response to a comment by Hordyk et al. on "A new approach for estimating stock status from length frequency data" Reply Coro, Gianpaolo; Scarcella, Giuseppe; Tsikliras, Athanassios C.; Dureuil, Manuel; Pauly, Daniel; Winker, Henning; Probst, Wolfgang Nikolaus; Demirel, Nazli; Dimarchopoulou, Donna <p>We thank Hordyk et al. (2019) for pointing out a typographical error in one of our equations, which has meanwhile been fixed in the online version of Froese et al. (2018) and addressed in a corrigendum for the printed version. We agree with Hordyk et al. (2019) that accounting for the pile-up effect in binned LF samples may be appropriate in, for example, tropical species with continuous reproduction, and we have provided for such correction as an option in the latest version of the LBB software. We note, however, that this correction as well as the LBSPR method of Hordyk et al. (2016) proposed by Hordyk et al. (2019) as an alternative to LBB leads to strong overestimation of exploitation and underestimation of stock status when compared with independent assessments of 34 real stocks from temperate and subtropical areas. As for the points raised by Hordyk et al. (2019) with regard to default priors for Linf and M/K, we maintain that these defaults are adequate for a wide range of exploited species. They can be easily replaced by users if better information is available. Warnings not to use LBB if LF samples do not show the typical asymmetric pattern were already provided in the original LBB paper and are repeated here.<br></p> 2019-01-01T00:00:00Z http://hdl.handle.net/20.500.12627/1000 Seasonal distribution of Trachurus mediterraneus (Steindachner, 1868) in the Golden Horn Estuary, Istanbul Demirel, Nazlı Seasonal changes in the distribution of an important commercial and recreational fish species, Trachurus mediterraneus (Steindachner, 1868), from the family Carangidae were investigated in the Golden Horn Estuary of Istanbul. Environmental conditions were also considered to evaluate distributional patterns in the region. Sampled fish size ranged between 7.5 and 20.1 cm in total length and 3.4 and 86.2 g in total weight during the sampling period. Adult individuals (> 12.5 cm) preferred not to be in the estuary during the summer period, while only immature adults were found with a 7.5-12.5 cm total length size range from May to August 2009. It was observed that on a regional basis this species was only found at the entrance of the Golden Horn. Environmental parameters such as surface temperature, salinity, and dissolved oxygen values did not display significant correlations with its distribution throughout the study period. However, chlorophyll a and Secchi disk values displayed significant negative correlations with the distribution of immature adults in the Golden Horn. 2014-01-01T00:00:00Z