Some biological aspects of four marine fish species in Iraqi marine waters, northwest Arabian Gulf

Abstract

The study described some biological characteristics of four commercially important fish species in Iraqi marine waters including Planiliza klunzengeri, P. subviridis, Acanthopagrus arabicus and Otolithes ruber from February 2020 to January 2021. The length and weight of individual fish caught were measured. The length-weight relationships were W= 0.027L2.715 for P. klunzengeri, W= 0.034L2.670 for P. subviridis, W= 0.030L2.867 for A. arabicus and W= 0.023L2.755 for O. ruber, and all species indicated negative allometric growth. The lower values of the relative condition factor (Kn) were found at the mid-lengths of P. klunzingeri and P. subviridis, and the large individuals for A. arabicus and O. ruber. Scales were used for age determination and measurements, and the back-calculated lengths-at-ages were calculated using the body proportional formula. Asymptotic total lengths (L∞) estimated were 29.6, 32.8, 44.9 and 70.6 cm for P. klunzengeri, P. subviridis, A. arabicus and O. ruber, respectively. These results could assist in fisheries management for the sustainable exploitation of these commercially important species in Iraqi marine waters.