Fishing - multispecies management approaches: evaluation

Conclusions

Of the multispecies management approaches explored here, three offered additional flexibility above the current ICES MSY approach to overcome choking effects while still controlling fishing mortality adequately enough to achieve good stock status. Conversely, the SFA Others pool approach performed the least well against biological performance indicators with TACs being consistently exceeded, leading to multiple stocks falling below sustainable levels. In addition, the SFA Others pool approach performed the least well against economic performance indicators. This was mostly driven by the poor stock statuses but also because of disproportionate effects between the fleets with the TR1, over 15 metre fleet benefiting more than other fleets. More stringent limits and/or additional safeguards for this management approach would be needed for it to become a viable alternative to the current system.

While the CFP implementation of interspecies flexibility did not offer much flexibility to significantly overcome choking, the relaxation of some limitations in the alternative implementation did alleviate choking effects further. Although, this was at the expense of exceeding sustainable levels of fishing for a number of stocks.

The quota points system approach is the only true multispecies approach and was able to alleviate choking to a similar magnitude as the interspecies flexibility approaches. As demonstrated here, though the quota points system does not directly control the fishing mortality of each stock individually, it was still able to achieve good stock status for all stocks.

Overall, the alternative interspecies flexibility approach and the quota points system may be the more obvious candidates for further exploration given their ability to noticeably alleviate choking while maintaining good stock status. This exploration should include testing different limits, additional safeguards and alternative model assumptions. It should also consider fleet profitability and not just income as a performance indicator and test the compatibility of these approaches with stock rebuilding plans.

Finally, all these management approaches alleviate choking effects by allowing TACs on some stocks to be exceeded to a greater or lesser degree. Therefore, alternative management choices to address choking without exceeding sustainable levels of fishing on choke stocks such as fleet specific technical measures, spatial or temporal closures should also be explored.