Investigating trade-offs in alternative catch share systems: an individual-based bio-economic model applied to the Bay of Biscay sole fishery.

An individual-based bio-economic model is presented and applied to the Bay of Biscay sole (Solea solea) fishery to investigate alternative quota management systems from a multicriteria perspective. For this study, the model integrates several institutional arrangements related to catch share management. The current French co-management system with nontransferability of quota is compared with an alternative individual transferable quota (ITQ) system in a context of transition to maximum sustainable yield. Trade-offs between ecological and socioeconomic impacts are highlighted and the effectiveness of governance scenarios is discussed in regard to the challenge of capacity adjustment. Results emphasize that the introduction of ITQs is expected to reduce by 40% the number of vessels in the fishery. While effectively mitigating the economic impacts of the transition phase to maximum sustainable yield, ITQs are also expected to increase substantially the fishing effort by trawlers, which may cause ecological concerns. The scenarios tested also include the simulation of a decommissioning scheme where subsequent decommissioned vessels are considerably different from the vessels that would lease out their quotas in an ITQ system, resulting in differentiated ecological and socioeconomic impacts between scenarios. [ABSTRACT FROM AUTHOR]