Population Dynamics and Stock Assessment of Atlantic Horse Mackerel (Trachurus trachurus) Stocks in the Western Egyptian Mediterranean Waters

Zeid Et Al., Salma M.

doi:10.21608/ejabf.2023.329301

Population Dynamics and Stock Assessment of Atlantic Horse Mackerel (Trachurus trachurus) Stocks in the Western Egyptian Mediterranean Waters

Document Type : Original Article

Author

Salma M. Zeid et al.

10.21608/ejabf.2023.329301

Abstract

The present study aimed to evaluate the fishery status of the Atlantic horse mackerel (Trachurus trachurus)stock in the western Egyptian Mediterranean waters. Random monthly samples of fish were collected during the period from April 2015 to March 2016, with a total of 1054 fish. Growth parameters were determined and the vectors of natural mortality (M) by age, total mortality (Z) and fishing mortality (F), length cohort analysis, and Beverton & Holt Yield per recruit analysis were performed by FiSAT and Virtual Population Analysis (VIT software) programs to estimate the limit and target reference points. The present results showed that the Von Bertalanffy growth parameters were L_∞ = 29.58 cm, K = 0.27 years^-1, and t₀ = -1.49 year. The mean values of Z, F and M were 0.828, 0.575 and 0.253 year^-1, respectively. The exploitation rate (E) was 0.694 year. The current yield per recruit (Y/R), biomass per recruit (B/R), and spawning stock biomass (SSB) at the current fishing mortality (0.575 year^-1) were 14.27, 31.35 and 12.15g, respectively. The percentage of the current B/R to the virgin biomass was 25.11%. The reference point F_0.1 = 0.27, and the limit reference point (F_MAX) was 0.48 year^-1. These two values are lower than the current value of fishing mortality (0.575 year^-). The ratio between F_Cand F_0.1was 2.128; this value indicates that T. trachurus stock in the Egyptian Mediterranean waters is at a high over-exploitation state.

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