Fecundity estimation of Atlantic cod ( Gadus morhua) and haddock ( Melanogrammus aeglefinus) of Georges Bank: Application of the autodiametric method

Abstract

Haddock, Melanogrammus aeglefinus (L.), and Atlantic cod, Gadus morhua (L.), are species of major commercial interest in the Northwest Atlantic and their spawning strategy is characterized by group-synchronous oocyte development and determinate fecundity. Recent advances in image analysis systems and the development of the autodiametric method have led to rapid assessment and accurate estimation of the annual egg production of an individual or its potential fecundity. In this study we estimated the corresponding autodiametric calibration curves for Atlantic cod and haddock of Georges Bank and used these to estimate potential fecundity of these two species near the southern limits of their geographic distribution. In addition, we explored the relationships between potential fecundity and different condition indices for these populations and found the hepatosomatic index to significantly increase the explanatory power of the fecundity–length relationship which is in agreement with previous studies on the influence of nutritional state on egg production.