Estimating the maturity ogitive for Northeast Arctid cod by a modified assessment model

Abstract

The exploitation (1967-77) of the Northeast Arctic cod is splitted in 12 different fisheries. The mesh assessment model is modified in order to estimate the maturity ogive on the basis of the length and the age distributions of the catches from these fisheries. The key fishery in the estimation is the gi11 net fishery in Division IIa which mainly takes part during the spawning season. The resulting ogives are similar to those derived by other methods for the same period. Although the estimated statistical variations of the results are underestimates due to unaccounted uncertainties in the fixed input parameters in the model, the present method may be an alternative or a check on other methods.