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Payne et al. (Can. J. Fish. Aquat. Sci. 66: 869-872, 2009) raised several points concerning the handling and interpretation of data that went into an analysis of the population dynamics of Georges Bank haddock that suggested a relationship between the fall phytoplankton bloom and recruitment (Can. J. Fish. Aquat. Sci. 65: 1076-1086, 2008). Their main points were the manner in which logarithmic transforms were applied, whether the 2003 year class was truly as large as estimated in a 2006 assessment, and if correlation analyses of zooplankton data should be reconsidered. The reply to these comments was aided by a new assessment which provided additional years of data and improved the quality of the recruitment time series. The reply analyses showed that the relationships were robust to the way the logarithmic transform was applied, the initial estimates of the size of the 2003 year class were correct, and relationships between recruitment and spring zooplankton biomass levels remain statistically insignificant. From these new analyses, the interpretations and conclusions reached in the original paper remain the same; the fall bloom has emerged as a candidate explanatory variable for the stock independent variation in haddock recruitment on Georges Bank. Payne et al. (J. can. sci. halieut. aquat. 66: 869-872, 2009) ont souleve plusieurs questions concernant la manipulation et l'interpretation des donnees utilisees dans une analyse de la dynamique de population des aiglefins du banc Georges qui a propose l'existence d'une relation entre la floraison automnale de phytoplancton et le recrutement (J. can. sci. halieut. aquat. 65: 1076-1086, 2008). Leurs interrogations principales portaient sur la facon dont les transformations logarithmiques ont ete faites, sur la classe annuelle de 2003 a savoir si elle etait vraiment aussi importante que l'indique une evaluation de 2006, ainsi que sur la pertinence de revoir les analyses de correlation des donnees de zooplancton. Notre replique a ces commentaires a ete facilitee par une nouvelle evaluation qui a ajoute des annees supplementaires de donnees et ameliore la qualite de la serie chronologique de donnees de recrutement. Les analyses faites pour notre replique montrent que les relations sont robustes en regard de la facon dont les transformations logarithmiques ont ete realisees, que les evaluations initiales de la taille de la classe annuelle de 2003 sont exactes et que les relations entre le recrutement et les niveaux de biomasse printaniere du zooplancton demeurent statistiquement non significatives. Suite a ces nouvelles analyses, les interpretations et les conclusions de l'article original restent les memes; la floraison automne ressort comme variable explicative de choix de la variation independante du stock dans le recrutement des aiglefins sur le banc Georges. [Traduit par la Redaction], In their comment on 'Does the fall phytoplankton bloom control recruitment of Georges Bank haddock, Melanogrammus aeglefinus, through parental condition?', Payne et al. (2009) raise a number of points concerning [...]

Abstract: In 2003, the Georges Bank stock of haddock (Melanogrammus aeglefinus) experienced the largest recruitment event recorded during its assessed history. Several hypotheses have been advanced to explain recruitment variability [...]