stock management implication of caspian kutum (rutilus frisii kutum kamensky, 1901) in iranian waters of the caspian sea

recently the previous caspian ecosystem is in a catastrophic condition which caused changes in the absolute and relative abundance of the commercially important caspian kutum (rutilus frisii kutum) in iranian waters. the paper presents estimates of yield-per-recruit and spawning biomass-per-recruit under various harvest strategies of fmax, f0.1, f30%. it proposes a method for estimating acceptable biological catch (abc) that accounts for large differences in the quality and quantity of information and available data. the current average y/r (with f=0.61/y, and tc=3.2 y) was 218.3 g per recruit, which indicates that the fishery is operating below the maximum y/r at 236.9 g when tc = 3.5 y. the y/r was the highest at fmax and f0.1, when tc = 4 y (244.8 g and 214.2 g), respectively. the f30% value was 0.85/y at tc of 4 y with the sb/r of 338.3 g. the fcurrent (0.61/y at current tc is 3.2 y) is higher than the corresponding reference points, f0.1 (0.47/y) and f30% (0.46/y). the abc of kutum was estimated at 7,850 mt in 2009-2010.