Growth and mortality of Atlantic bigeye (Priacanthus arenatus) in the coastal waters Liberia

Abstract

Growth, mortality and yield-per-recruit of Atlantic bigeye (Priacanthus arenatus - Cuvier, 1829) were examined in the coastal waters of Liberia between June 2020 and February 2021. Monthly length frequency data were analyzed using FiSAT (FAO ICLARM Stock Assessment Tools) software for estimating population parameters, including asymptotic length (L), growth co-efficient (K), mortalities and length at first capture to assess the status of the stock. The minimum and maximum total lengths was 12.1 cm and 38.5 cm, while minimum and maximum total weights was 45.2 gm and 450 gm, respectively. The mean total length and body weight of the coastal waters of Liberia was 21.62 (± 3.13-) cm and 125.4 (± 65.74) gm, respectively. The L and K for males were estimated at 37.80 cm and 1.20 yr-1, respectively. The growth pattern of P. arenatus showed negative allometric nature of growth (b < 3). The maximum life span (tmax) of P. arenatus was 2.50 years. Total mortality (Z) by length converted catch curve was estimated at 3.38 yr-1. The rate of natural mortality (M) was calculated as 1.89 yr-1 and the fishing mortality (F) was 1.49 yr-1. The exploitation rate (E) of was 0.44. The conservative limit of exploitation (E10) of P. arenatus was 0.50. The current exploitation rate was less than the predicted E10 of P. arenatus. Thus, the stock of P. arena was found to be under exploited in the investigated area.

Keywords: Growth and mortality parameters and exploitation rate in the` coastal waters Liberia.