Yield and Biomass-per-recruit Analysis of Tiger Tooth Croaker (Otolithes ruber) in the Northwest of the Persian Gulf

Effects of age at first capture (tc) and fishing (F) as well as natural mortalities (M) on yield and biomass-per-recruit of tiger tooth croacker, Otolithes ruber were evaluated in the northwest of the Persian Gulf using the Beverton-Holt model. The yield-per-recruit (Y/R) was 175 (g/r), which was less than maximum yield-per-recruit value (217 (g/r)) at fishing mortality of 1 year-1. Current F (FCUR) was estimated to be lower than the level that produced maximum potential yield-per-recruit (FMAX) at all scenarios of tc and M=0.50. Increases in yield from Fcur to Fmax ranged from 4.3% to 36.4%, depending on the level of M and tc used in the model. However, this relatively small gain in yield corresponded to an increase in F of 471.58%. The biomass-per-recruit (B/R) decreased rapidly with increasing values of F and the trend in all scenarios of tc was similar with minor differences. The B/R represented about 65% of the virgin biomass and current fishing mortality rate (Fcur) was less than the Fmax and it was near the F0.1, indicating that O. ruber was slightly under exploited. Fcur (0.44) in estimated population was well lower than the Fmax (1) and it was close to F0.1 (0.5).