Study of some biological aspects and population dynamics of striped piggy fish, Pomadasys stridens (Forsskal, 1775), from Lake Timsah, Egypt

Authors

Department of Zoology, Faculty of Science, Zagazig University, Egypt

10.22092/ijfs.2025.134259

Abstract

The present investigation was carried out to study the age, growth, length-weight relationship, spawning season, length at first sexual maturity, length and age at first capture, mortality, and growth performance of the commercial striped piggy fish, Pomadasys stridens (Forskål, 1775), inhabiting Lake Timsah in Egypt. Fish specimens collected during the period from January 2022 to December 2022 were selected to represent all fish size categories in the catch. The age distribution covered age groups I to V. Total length ranged from 8 to 17.8 cm, while total weight varied from 10.57 to 87.65 g. There was no significant difference between the length–weight relation (LWR) parameters of sexes and pooled data. The overall LWR was found to be W=0.0112×L3.0496. It was found that both males and females matured at a total length of about 12.3cm for males and 12.7 cm for females. The natural spawning period for P. stridens in Lake Timsah is at the end of spring and early summer, from May to July. The von Bertalanffy growth parameters were not significantly different between males and females. The model parameters for both sexes were:  L=21.01 cm, K= 0. 245, and t0= -1.5475. The annual rates of total, natural and fishing mortality for male and female P. stridens were calculated as 2.0405 Yr–1, 0.6367 Yr–1, 1.4038 Yr–1 and 2.0151Yr–1, 0.7035 Yr–1, 1.3116 Yr–1 , respectively. The current exploitation rate 'E' was estimated at 0.69 and 0.65 for males and females.

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