Aspects of the early life history of galjoen Dichistius capensis

Abstract

Laboratory experiments were conducted to determine the relationship between temperature and embryonic duration for fertilized galjoen eggs, and to examine the pattern of endogenous food utilization in early galjoen larvae. Embryonic duration decreased with increasing temperature, the relationship being best described by a power function with a negative slope. The lower lethal limit for developing eggs lay between 14 and 16°C. Newly hatched larvae rapidly exhaust their endogenous food reserves, the yolk sac being depleted at a slightly faster rate than the oil globule. Larvae approach first-feeding at 110 h after hatching at 18°C, and exhibit a short time period to irreversible starvation. Galjoen larvae appear to be particularly vulnerable to catastrophic starvation-induced mortality in nature. © 1994 Taylor & Francis Group, LLC.