Effects of environmental variability on recruitment and bioeconomic modelling in the Pacific sardine ( Sardinops sagax caerulea) fishery from Magdalena Bay, Baja California Sur, Mexico

Abstract

Ricker’s stock-recruitment equation, including the multivariate ENSO index (MEI ) as an environmental variable, was fitted to data of the Pacific sardine (Sardinops sagax caerulea) fishery from Magdalena Bay, Baja California Sur, Mexico. The equation was then incorporated into an age-structured, bioeconomic model. Uncertainty was incorporated by using environmental fluctuations; seven-year projections, equivalent to one sardine generation, were computed. Five management options were considered in the projections: open access, effort at maximum sustainable economic yield (fMSE ), catch at maximum sustainable yield (CMSY), equivalent effort level applied in the year 2004 (f2004), and an arbitrary catch quota of 40000 tons (CQ40000). Projection results were summarised by the indicator Net Present Value (NPV) of the fishery for the modelled period. The strategies that involved some regulation in the effort level (fMSE and f2004) yielded the largest NPV. On the other hand, the strategies that involved regulation of the catch predicted—in addition to a lower NPV—a substantial increase in the effort to achieve the desired catch level. This study is the first bioeconomic approach for a sardine fishery management plan in this region