Estimate of the Maximum Sustainable Yield of Sergestid Shrimp in the Waters off Southwestern Taiwan

The sergestid shrimp, Sergia lucens is one of the major marine resources in the waters off southwestern Taiwan. The maximum sustainable yield (MSY), total allowable catch (TAC) and fishing effort at MSY (EMSY) of the sergestid shrimp in this area were estimated to be 1008 tons, 907 tons and 11292 vessel-day, respectively by using the surplus production model with deterministic observation-error estimator approach based on a catch and effort series from 1997-2008. Furthermore, the mean MSY, TAC, and EMSY with 95% CI were estimated to be 1011 (842-1243) tons, 910 (758-1119) tons, and 11296 (1075811807) vessel-day, respectively from the stochastic models. The estimated biomass showed a slightly decreasing trend during the period of 1997-2008 suggesting that the TAC should be included in current management measure to ensure a longterm sustainable utilization of this stock in spite of no overfishig and overfished occurrence.