Evaluation of bag-and-size-limit options in the management of summer flounder Paralichthys dentatus

The conundrum probed here is the seeming divergence in outcomes of the management program presently in place in the Mid-Atlantic Bight for summer flounder; namely that increasing restrictions on catch to limit quota exceedances and maintain satisfaction in the fishing experience for the angler may not be simultaneously achievable. The corollary quandary is the loss of the bag limit as an operative management tool, as efforts to restrain landings became increasingly burdensome, thereby placing inordinate reliance on the size limit (and season). To investigate options that might promote increased angler gratification and reduce discard mortality without eliciting quota exceedances, we examine a number of alternative management strategies that might (a) bring bag limits back into the manager's repertoire, (b) trade discards for landings, thereby increasing angler gratification, and (c) provide an increased number of fish per unit of landings weight, thereby realizing for the angler a greater number of kept fish. Options investigated include standard bag-and-size limits, boat limits, dual-size limits implemented with both a minimum and maximum size, slot limits, and a cumulative-size limit in which landings are restrained by a total number of inches of landed fish. Comparing all fishery options reveals that dual-size, slot, and cumulative-size limits provide the best resolution to the posed conundrum. Dual-size and slot limits improve landings relative to fishing mortality, but the cumulative-size limit outperforms both by a substantial degree. The options in part permit increased landings relative to discards and this moves discard mortality to landings, a useful outcome. However, the probability of mortality due to discard is low in summer flounder and, thus, relatively little gain occurs in simply minimizing discards. Rather, successful management options are those that permit effort to be transferred from larger fish to smaller fish, thus reducing total weight landed relative to total number. The cumulative-size limit is the most successful approach in accomplishing this feat.