Growth parameters and stock assessment of Carangoides bajad Forsskal, 1775 (Carangiformes: Carangidae) in Jeddah fisheries

Abstract

ABSTRACT The stock status of Carangoides bajad in Jeddah fisheries was assessed by estimating the growth parameters, mortality rates and size at first capture (Lc), then applying the results to estimate the yield and biomass per recruit. The length-weight relationship could be described by the power equation: W = 0.011 L3.019 (R2 = 0.99) for combined sexes. Von Bertalanffy Growth Parameters L∞, K and t0 were estimated to be 71.53 cm, 0.224 year −1, and −0.52 year, respectively. The total, natural, fishing mortality coefficients and exploitation were calculated to be 0.72 year −1, 0.337 year −1, 0.383 year −1, and 0.53 year −1, respectively. Beverton and Holt (1957) model was used to estimate the yield and biomass per recruit at Fcur and Lc and found to be Y/R = 291 g and B/R = 759 g. Compared with the two biological reference points Fmax = 0.56 year −1 and F0.1 = 0.346 year −1, the Fcur value was very close to the F0.1 value required to get the optimum Y/R. We recommend avoiding any increase in Fcur, and increasing Lc to be 38 centimetres to increase the B/R from 759 g to 793 g, which would increase the probability of sustaining sufficient recruitment to the fishery of C. bajad in Jeddah fisheries.