Publication Abstract

Recruitment variation predicted by fecundity in marine fishes

S.J. Rickman, N.K. Dulvy, S. Jennings and J.D. Reynolds

An understanding of the processes that control recruitment variation is central to explaining the population dynamics of fishes and predicting their responses to exploitation. Theory predicts that interannual variation in recruitment should be positively correlated with the fecundity of fish species, but empirical studies have not supported this hypothesis. In this study, a phylogenetic comparative approach is adopted, which accounts for evolutionary relatedness among stocks and species, to investigate this relationship. The mean fecundity of fishes from 52 stocks at the mean length of maturity is calculated and this is related to interannual recruitment variation. It was found that in 13 of 14 comparisons between stocks or closely related species, the stocks with higher fecundity have higher recruitment variation. This was true whether or not spawning stock size was controlled. When the analyses were repeated using a traditional cross-species approach, which did not account for the evolutionary relatedness of stocks, the relationships were not significant. This is the first empirical study to link fecundity with recruitment variation and suggests that fecundity is an important component of fish stock dynamics.

Reference:

S.J. Rickman, N.K. Dulvy, S. Jennings and J.D. Reynolds, 2000. Recruitment variation predicted by fecundity in marine fishes. Canadian Journal of Fisheries and Aquatic Science, 57(1): 116-124.