A total of 1457 random specimens of newly established population Metapenaeus affinis w ere collected monthly during the period from July 2020 to June 2021 at Boughaz El-Ma’deya landing center from Abu Qir Bay (Alexandria, Mediterranean Sea, Egypt) using commercial shrimp trawlers. The study aims to shed light on the growth pattern and stock assessment of this newly established species.
Shrimp specimens were sexed and the total length (TL), the carapace length (CL) and the total body weight (Wt) were measured. According to the results of the present study, the catch varied in lengths between 5.4 cm and 16.0 cm TL and a t length of 13.5 cm the population is composed of 100% females. The lengths from 9cm to 13.5cm represented 78.48% of female catches and the lengths from 8cm to 11cm represented 85.10% of the male catches. The overall sex ratio (F: M) was 1.00: 0.58 and Chi-square test reflect significant differences (X2 =172.8; df =1; P < 0.05). The growth parameters were calculated for males, females and combined sexes (Table 1) where, the von-Bertalanffy’s growth parameters (L∞, K and to) were calculated from the analysis of length frequency by Bhattacharya’s method. The fisheries parameters were calculated for the population (Table 2).
The t est of the allometric coefficients (b) of CL was shown negative allometry growth for males, females and sexes combined. The values of "b" for L-Wt. relationship reflect isometric growth only for males. Females and sexes combined showed a pattern of positive allometric growth.
The study of fishery parameters revealed that Metapenaeus affinis was still un-exploited.
Further studies were recommended in other fishing grounds for finding out of its spawning and nursery grounds in the Egyptian waters . The study of the reproductive biology for this shrimp species was also recommended.