Abstract

A method is introduced which uses otolith growth rate to provide a direct estimate of K, the von Bertalanffy growth rate parameter. We obtained estimates of K of 1.078 ± 0.687 y-1 and 0.621 ± 0.076 y-1 for the queen snapper, Etelis oculatus, by two variations of the method. There is no significant difference between the two estimates of K, or with an earlier value estimated with the use of ELEFAN 1. We suggest that this method may be used where otolith microstructure analysis does not allow for ageing the fish either by conventional counting of rings or even by analysing the width of growth increments. We acknowledge that from a statistical perspective, with one of the variations we may have violated the assumption regarding the independence of the observations used in the linear regression. Notwithstanding this, we propose that estimates of K by this general method can, at least, be a starting point or seed value for the use in other length based methods

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