Optimizing harvesting strategies of the white shrimp fishery in the Gulf of Nicoya, Costa Rica

A time data series of catch data reported at the Gulf of Nicoya for the semi-industrial while shrimp trawling fleet between 1990 and 2003, and population parameters obtained for that species, were both used in an analysis implemented in a semi-automated, age-structured simulation model (FISMO). Based on the strong seasonality of shrimp stocks, we explored the possibility to find evidence of overfishing as a result of fishing effort after the main reproductive peaks. It was found that the current fishing intensity (F) is only 26% with respect to that required for the maximum sustainable yield (MSY), but it is almost three times more profitable. These results lead us to conclude that further increases in fishing effort should not be encouraged: in this way the spawning stock may be maintained at relatively high levels for successive years and the fishery would have more chances to be sustainable in the long term.