Age and growth of <i>Lutjanus kasmira</i> (Forskål) in Hawaiian waters

Abstract

The growth of Hawaiian taape, Lutjanus kasmira , was studied by examining otoliths and by analysing length‐frequency distribution. Annual hyaline and opaque markings were visible in whole mounts of sagittae, which were verified by enumeration of daily increments with a scanning electron microscope (SEM) and through marginal increment analysis. The von Bertalanffy growth curve was fitted to the data, resulting in: image where t. l . is total length (cm) and t is age (years). SEM observations revealed that the slowgrowth hyaline zones were composed of daily increments too small (0.4–0.8 μm) to be resolved optically. Thus, age estimates derived by numerically integrating otolith growth rate data obtained with a light microscope showed a negative bias, resulting in overestimation of growth rates. Parameter estimates obtained from three different types of length‐frequency analysis were also unstable. This was due, at least in part, to differences in the size composition of fish sampled with different fishing gears and from different depths. The growth rate registered in Hawaii falls within the reported growth coefficients of lutjanids, whereas it is one of the highest in the Pacific and clearly higher than a deep‐water lutjanid species growth in Hawaii. Probably, this high growth rate may have been enhanced by the relative lack of competitors in the depauperate Hawaiian marine fish community.