Population structure of the striped piggy Pomadasys stridens in the Gulf of Suez

Abstract

The striped piggy Pomadasys stridens is a commercial species in the trawl catch of the Suez Gulf. The lengths of collected species ranged from 6.6 to 19.0 cm and showed positive allometric growth W = 0.0074L3.2466. The determination of age derived from the otolith reading revealed that the life span of this species is seven year, which is considered relatively short. The von Bertalanffy equation was calculated as Lt = 20.4 (1−e−0.29(t+1.36)). The estimated size at 50% sexual maturity corresponded to an age close to 1 year, where 9.7 and 11.0 cm were sizes for males and females respectively. The highest Gonado-somatic index (GSI) values were recorded in April and May. The relative yield per recruit (Y’/R) and the estimated biological reference points showed that the species is heavily overexploited which may lead to recruitment overfishing. However, the fishing mortality rate was greater than the target and limit reference points. Also the percentage of the relative biomass per recruit values (which correlated to F0.1 and Fmax) to the virgin biomass was 20.45% and 37.00% respectively, which exceed the percentage of the current biomass per recruit to the virgin biomass (15.49%). The fishery of this species needs some management regulations for the development of its production. Keywords: Pomadasys stridens, Ageing, Mortalities, Yield per recruit, Gulf of Suez