Bioeconomic analysis and management aspects of metapenaeus shrimp fisheries in Pakistan

Abstract

Fishery input (FI) and fishery output (FO) data, 1984-2009, related to Metapenaeus shrimp fisheries sector in Pakistan is analyzed in order to access its bioeconomic and management aspects. The maximum, minimum and average catch of this fishery resource remained 14824 t (1984), 5004 t (2006) and 7925 t y-¹, correspondingly. Data was analyzed by using two specialized fishery software i.e. CEDA and ASPIC. Three surplus production models (SPMs) viz. Fox (FM), Schaefer (SM) and Pella-Tomlinson (PTM) were used in CEDA. Furthermore, error assumptions (EAs) viz. normal (NEA), log normal (LNEA) and gamma (GEA), for each SPM were also applied in CEDA. Two SPMs, FM and LM, were used in ASPIC. In CEDA by using an initial proportion (IP) of 1, FM estimated MSY, CV and <em>R²</em> as 6474 t (tons), 0.048 and 0.670 for NEA. While, the computed values of these parameters for LNEA remained as 6108 t, 0.061 and 0.574, correspondingly. For this model, GEA produced minimization failure (MF). Estimated MSY for all EAs by SM and PTM were remained same viz. 7731 t, 6959 t and 7102 t, correspondingly. FM results showed the highest value of <em>R²</em> (0.670). In ASPIC, FM estimated MSY, <em>F_MSY</em>, CV and <em>R²</em> as 6200 t, 0.219 y^-1, 0.054 and 0.896, respectively, whereas, LM computed same parameters as 6769 t, 0.207 y^-1, 0.100 and 0.846, correspondingly. The obtained results suggest that this fishery resource is overexploited. Thus, harvest levels of this fishery resource must be lowered for their sustainable maximum economic contribution and conservation as well.