ASFB Home > The effects of spatial and temporal factors on the abundance of seven key finfish species along south-western Australia.

Growth and Nutritional Condition in a Tropical Larval Fish and its Importance to Replenishment

Tove Lemberget, Mark McCormick and David Wilson

James Cook University, TOWNSVILLE, AUSTRALIA

THEME: ASFB

Understanding the processes that control recruitment in fish populations is essential for predicting cohort strength. In tropical waters starvation has been suggested to make up a substantial source of mortality during early life stages of tropical species. The aim of this study is to investigate the influence of growth and nutritional condition in a tropical reef-associated fish to the magnitude of monthly larval replenishment. Larvae were sampled over 18 lunar months using light-traps off San Blas, Panama. Information on growth and age was derived from otoliths, while estimates of nutritional condition were determined histologically, using the density of liver hepatocytes as a relative measure of lipid storage. Data are used to address three hypotheses: a) that the variation in lunar light-trap catches are positively correlated with variation in growth during specific periods of the larval life b) that there exists a relationship between nutritional condition upon capture, growth-rate and magnitude of replenishment, suggesting that an increase in condition enhances growth and replenishment, and c) that there will be different growth profiles between wet- and dry-season, and higher growth-rate, better nutritional condition and a larger monthly larval supply during wet-season compared to dry-season.

This abstract is a contribution to the larval section of the AFBS meeting.