Bioeconomic analysis of the effects of modifying the trawl extension piece with T90 netting

Abstract

We assessed the effect of the European discards ban on the profitability of bottom trawlers in a case study fishery (GSA06, NW Mediterranean) in the transition period 2017-2018, when the species that characterize the fishery, viz. hake and red mullet, fall under the discards ban. We used the results of Sola and Maynou (2018) to simulate the adoption of a modified bottom trawl design using a T90 extension net to reduce the catches of undersize hake and red mullet. Our results show that the economic impact of the former discards brought to land on the fisheries operators is expected to be low, regardless of the possible commercial use of these unwanted catches. Furthermore, the adoption of a more selective bottom trawl design would increase the escape of undersize individuals and likely reduce fishing mortality of the target species, contributing to stock rebuilding and providing higher income to the fisheries operators in the medium to long term.

“Crash landing” obligation for Mediterranean mixed fisheries: Evaluation of management strategies using bioeconomic modelling in the Aegean Sea

“…The sale of former discards will bring small additional profits but will not compensate losses due to the landing of target species or sorting and handling costs (a "crash landing" obligation). Sola and Maynou (2018) produced similar figures but the Spanish fleet was shown to bounce back in the long term despite the significant losses of revenue in the short term. In fact, anything beyond the short to medium term depends on the initial conditions introduced in the model (e.g.…”

“…The CFP could create incentives to improve the harvest patterns (Prellezo et al 2016) by enabling exemptions specific to each fishery and providing a regionalization of advice. Also, gear modifications could improve selectivity and enhance sustainability (Sola and Maynou 2018) and spatiotemporal closures could assist the rebuilding of fisheries through an increase in the SSB of targeted stocks (Russo et al 2017). Measures proposed for solving the discards problem in Europe vary in form and application status (Sigurðardóttir et al 2015).…”

Co‐viability of a Mediterranean demersal fishery affected by the discard ban under alternative management scenarios

“…The simulations were carried out with FLR using the built in biological libraries of the model (particularly FLCore and FLBRP, see http://www.flr-project.org/). The economic submodel (Annex S1) was codified in R for this work based on the economic submodel of MEFISTO (Maynou, ; Sola & Maynou, , ).…”

“…The policy objective was to reach F msy for as many stocks as possible by 2020 proje ct.org/). The economic submodel (Annex S1) was codified in R for this work based on the economic submodel of MEFISTO (Maynou, 2014;Sola & Maynou, 2018a, 2018b).…”

Monitoring the Environmental, Social and Economic Dimensions of the Landing Obligation Policy

“…The LO may also have positive effects on the target population structure and species length composition, because it might reduce recruitment overfishing and thus assist in rebuilding previously overexploited European stocks (Froese et al, 2018). If changes follow expectations, the LO may help to achieve values of landings at/above maximum sustainable yield (MSY), in accordance with targets for healthy stocks and accurate stock assessments (Prellezo et al, 2016;Sola and Maynou, 2018). However, an important issue to be resolved is the full reporting of catches (Condie et al, 2014) and the compliance with regulations (Maynou, 2019), which will require high levels of control and monitoring coverage (James et al, 2019), and the creation of the right incentives that will enable the support of the measure by the fishing sector (Stithou et al, 2019).…”