Trade-offs between employment and profitability in a Mediterranean Sea mixed bottom trawl fishery

Abstract

The exploitation of mixed fisheries leads to trade-offs between fisheries rent, production (landings) and resource conservation because harvest rent cannot be optimized simultaneously for all species. Additionally, the exploitation of mixed fisheries by heterogeneous fleets complicates their management because of the necessity to allocate catch or effort quotas, under some criterion of efficiency or equitability. The allocation of fishing opportunities impacts directly on the availability of jobs in fisheries. To analyse the trade-offs between employment and profits in mixed fisheries, an optimization bioeconomic model was built for the three bottom-trawl fleet segments operating in the Catalonia demersal fishery (NW Mediterranean Sea). The fishery is subject to a multiannual management plan to align fishing effort with the fisheries mortality that would produce the maximum sustainable yield. The optimal effort allocation among the three fleet segments were compared subject to alternative fisheries management policies: (i) maximum sustainable yield, (ii) maximum economic yield, (iii) maximum labour remuneration, (iv) pretty good yield, and (v) equilibrium biomass larger than biomass at maximum sustainable yield, taking into account the multispecies nature of the fishery. The results show that all management policies provide higher profits than current. In the first three scenarios, high profitability can be made compatible with a lower number of better paid jobs, because the optimal allocation of effort in most scenarios would imply a reduction in the number of vessels. The results also show that the current number of vessels and effort distribution (which are the result of a historical process, rather than the results of a management strategy) are far from any optimum.