اکبر عباس زاده

Assesment of some reproductive biological aspects including sex ratio, GSI, Fecundity and spawning season of the fish Nemipterus japonicus (Bloch, 1791), were studied from September 2012 to February 2013 by regular monthly collections in coastal waters of Persian Gulf, Bushehr Province. A total of 315 specimens, including 101 males, 184 females and 30 immature were collected. Results indicated that, sex ratio was 1:1.83 (male to female). Females showed a higher frequency than males in samples (64.56%). The relationship between length and fish weight for males was: W=0.025FL2.89, R2=0.95 and for female was : W=0.052FL2.65, R2=0.85 respectively. There is no significant difference between length- weight relationship of male and female. Monthly distribution of GSI for female and male Nemipterus japonicus, showed that the GSI values have one peak at spring and in May, distinctly which this was in agreement with spawning results. Mean of absolute and relative fecundity was 474213 and 2293.778, respectively.