Spawning and larval husbandry of flounder ( Paralichthys woolmani) and pacific yellowtail ( Seriola mazatlana), new candidate species for aquaculture

Abstract

This paper describes the spawning and larval rearing of a new species of flounder ( Paralichthys woolmani) and Pacific yellowtail ( Seriola mazatlana) for aquaculture in Ecuador. Experimental production of these species has been conducted for the first time from eggs in captivity. Broodstock flounder were conditioned to spawn through temperature manipulation. Pacific yellowtail spawned under natural environmental conditions. Production of flounder fingerlings has been steady but survival rates remain low (3–8%). Survivals ranging from 0–70% were achieved throughout larval rearing of Seriola, however, high mortalities caused by diseases, cannibalism and weaning onto artificial diets during and after metamorphosis reduced the average survival rates through the juvenile stage to less than 1%. Epizootics of epitheliocystis and Vibrio alginolyticus have repeatedly occurred during the early developmental stages and remain the bottleneck to sustainable mass production of S. mazatlana and P. woolmani fingerlings.