Linking Biological Parameters to Fishery Management: Stock Assessment of Green Tiger Prawn, <i>Penaeus semisulcatus</i> De Haan, 1844 Along the Red Sea Coast of Saudi Arabia.

Abstract

<i>Penaeus semisulcatus</i> is the dominant commercial prawn species along the Saudi Arabian coast in the southeastern Red Sea, yet its population dynamics remain poorly understood. This study examined growth, maturity, and mortality using fishery-independent samples obtained during trawl surveys off Jizan and Al Qunfudhah between October 2022 and September 2023. A total of 85,909 individuals were examined, exhibiting carapace lengths (<i>CL</i>) between 1.29 and 56.14 mm and weights (<i>W</i>) ranging from 0.91 to 94.99 g. The sex ratio (1:1.06) was slightly male-biased. The <i>CL</i>-<i>W</i> relationships were <i>W</i> = 0.00427·<i>CL</i>^2.50 for females and <i>W</i> = 0.01274·<i>CL</i>^2.16 for males. The von Bertalanffy growth parameters were <i>CL</i>_∞ = 60.16 mm, <i>K</i> = 1.03 year^-1 for females and <i>CL</i>_∞ = 48.10 mm, <i>K</i> = 1.02 year^-1 for males. Females first matured at a <i>CL</i> of 22.09 mm. Exploitation rates (0.63 for females and 0.69 for males) and spawning potential ratio analysis indicated severe overfishing, with spawning stock biomass reduced to 19% of its unexploited level. These results highlight the necessity for immediate management intervention. Reducing fishing effort by half, extending seasonal closures, and improving the selectivity of trawl gear are advised to facilitate stock recovery and support sustainable exploitation in the region.