Abstract
Present study was aimed to investigate the age structure, growth parameters, natural and fishing mortality coefficients of the common carp (Cyprinus carpio) in Mangla reservoir, Pakistan. To assess the parameters and infer on the degree of exploitation, the fork length frequency data were analyzed using the FISAT (ELEFAN I) computer program. The parameters of the von Bertalanffy growth curve for length were L-infinity = 80.33 cm, K = 0.60 yr(-1), t(o) = -0.39 year and longevity potential = 5.0 years. The instantaneous coefficient of mortality of the population were estimated to be, total mortality (Z) = 1.22 years, natural mortality (M) = 0.89 and fishing mortality (F) = 0.33. The stock showed a growth performance (cent) value of 3.588. The current exploitation rate of the species was calculated as 0.27. The analysis of relative yield per recruitment, and relative biomass per recruitment showed that the maximum allowable exploitation rate at Maximum Sustainable Yield (MSY) for the common carp fishery in Mangla reservoir is 0.63 which is more than the currently observed exploitation rate. The results suggest that common carp stock in the reservoir is not overfished and is within safe exploitation limits. It is recommended that regular monitoring program for the stock should be in place and any proposal for a change in exploitation rate should be assessed according to the stock status at that point of time.