Population structure of the European anchovy, Engraulis encrasicolus (Linnaeus, 1758) in Lake Manzala, Egypt

The present study is to identify the population and stock characteristics of Engraulis encrasicolus in the Mediterranean lagoon “Lake Manzala” of Egypt. A total of 1536 specimens were collected seasonally by a local trammel net (El-Balla), from 2019 to 2021. The length ranged from 4.2 to 12.1 cm, where the dominance was of medium sizes. Two age groups were observed with a short longevity (tmax = 3.16 y). Parameters of Von Bertalanffy, L?, and K, were estimated as 12.52 cm and 0.95 y-1, respectively. The growth performance index (Ø) was estimated as 2.17, expressing liner growth and environmental suitability. The calculated length at first maturity (Lm) = 8.1 cm, compared to 6.9 cm of length at first capture (Lc), expressing high fishing effort. Mortality indices include: total mortality (Z) = 3.71 y-1, and natural mortality (M) = 1.46 y-1. According to biological reference points, Fopt = 0.73 y-1 and Flimit = 0.97 y-1, the fishing mortality (F = 2.25 y-1) indicated overfishing of the anchovy stock in Lake Manzala. The current exploitation rate, E = 0.61 expressed the occurrence of overexploitation. Based on the results, reducing fishing efforts is vital to maintaining stock stability