Evaluating Alternative Management Options in the Gulf of Mexico Private Recreational Fishery
Principal Investigator: David Chagaris
Co-Investigators: Mike Allen and Ed Camp, University of Florida
Funding Source: The Pew Charitable Trusts
Seasonal closures are commonly used in recreational and commercial fisheries but they may be less effective when effort is merely displaced to the open season or in multispecies fisheries that allow for discarding to continue while other species are targeted. The latter is especially true for the valuable multispecies recreational reef fish fishery in the Gulf of Mexico, where discard mortality is high and it can be difficult to avoid catching one species while fishing for others. We evaluated the utility of complete bottom fishing closures (in addition to already mandated harvest closures) that would temporarily prohibit recreational reef fishing as a means to control effort, reduce the amount of dead discards, and improve stock status of multiple species. In this study we developed age-structured population models for six Gulf of Mexico reef fish species that dominate the recreational catch, with each model linked to a monthly effort dynamic model for the recreational fishery. The effect of closing any given month(s) varied across species and resulted in tradeoffs, such that some closures may result in positive effects on biomass of one species and negative effects on others. For example, a spring closure was predicted to have positive effects on red snapper spawning stock biomass but negative effects on gag due to the contrasting patterns in harvest rates during those months. The tradeoffs were found to be more severe when a high proportion of affected trips were assumed to shift to the open season. The closure scenarios that were most likely to reduce dead discards without negatively impacting harvest, spawning biomass, or total effort occurred in late winter and early spring (March & April). In evaluating seasonal closures, the gains in biomass and reductions to dead discards must be weighed against the socio-economic tradeoffs, in terms of lost effort-generated revenue at various spatial and temporal scales and angler dissatisfaction.
See more research like this on our Faculty Lab pages!