Discards and revenues in multispecies groundfish trawl fisheries managed by trip limits on the U.S. West Coast and by ITQs in British Columbia

The problem of multispecies fisheries, in which more productive and less productive species are caught together, is approached differently in the multispecies groundfish trawl fisheries of the U.S. West Coast and British Columbia (B.C.). In 1997 their management systems diverged: the former continued using trip limits, but the latter turned to individual transferable quotas (ITQs) combined with full observer coverage and the deduction of marketable discard mortality from quotas. U.S. requirements to rebuild overfished West Coast species have led to reduced trip limits, restrictions on fishing gear, and large area closures, which have decreased catches of species that are not overfished, increased discards of marketable fish, and decreased per-vessel groundfish income to US$220,000. In B.C., total catches have remained stable while individual incentives to retain marketable catches and to improve economic efficiency resulted in low marketable discard fractions, increased ex-vessel prices, and higher per-vessel revenue (US$420,000–US$500,000). If the B.C. system were implemented in the West Coast fishery, total revenue would probably improve through increased use of species that are not overfished, lower marketable discard fractions, and higher ex-vessel prices. Revenue increases may be hampered by restrictions imposed by the overfished species, but would probably exceed the additional observer costs