Mixed fisheries management: Is the ban on discarding likely to promote more selective and fuel efficient fishing in the Dutch flatfish fishery?

- High fuel prices have created incentive for fishers to switch to lighter, more fuel-efficient gear.
- A discard ban has the potential to reduce fishing effort and change fishing behaviour.
- A discard ban increases the economic incentive for switching to the pulse gear.

We model the potential effects of a discard ban on the annual fishing strategy of individual fishers in a mixed fishery under individual quota management. The North Sea beam trawl fishery, which catches large amounts of undersized plaice, is used as a model system. Under a discard ban, fishing is restricted to the fishing grounds and weeks where the maximum revenue can be realised with other species while catching the quota of the restricted species with a reduced bycatch of undersized fish. Model results suggest that, if properly enforced, a discard ban provides an incentive to implement more selective fishing gears that catch fewer small fish and are more fuel efficient (pulse trawl). If a discard ban is not properly enforced, restrictive quota do not necessarily result in the intended decrease in discarding as the fishery continues to fish while discarding the over-quota catch and least valuable size classes caught.