Growth and mortality of the European hake Merluccius merluccius (Linnaeus, 1758) from the North of Moroccan Atlantic coasts

Abstract

Growth and mortality studies on fish are considered crucial to the comprehension of species biology and population dynamics. This work aims to study the growth and mortality of Merluccius merluccius (Linnaeus, 1758) from the North Atlantic coasts of Morocco. A total of 1001 European hakes was sampled from trawler’s fishery during the period from August 2017 to August 2018. Growth parameters were computed for the European hake males and females by applying the von Bertalanffy growth formula. The asymptotic lengths (L∞), growth coefficients (k) and the theoretical age at zero-length (t₀) for females and males were; L∞ = 80.19 cm, k = 0.27 year⁻¹, t₀ = –0.472 year⁻¹, and L∞ = 69.15 cm, k = 0.31 year⁻¹, t₀ = –0.426 year⁻¹, respectively. The total mortality rate (Z), natural (M) and fishing mortality (F) were estimated as Z = 1.49, M = 0.51 and F = 0.98 for combined sexes. The estimated exploitation ratio (E = 0.66), indicated overexploitation of the M. merluccius in the North Atlantic coasts of Morocco.