According to an article published by Enaca, in 2005, the Rayong Coastal Fisheries Research and Development Center (Rayong CFRDC) made a breakthrough in mouse grouper Cromileptes altivelis larval rearing. The center uses the a simple recirculation system for their broodstock holding facilities. The broodstock tanks are rather small at 3×5×1.2 m. Although mouse grouper broodstock successfully spawn in these tanks, egg production is low, which limits fingerling production.
Rayong CFRDC also operates a large broodstock holding cage facility at nearby Koh Samet. This facility holds broodstock of several grouper species including P. maculatus, E. fuscoguttatus, E. lanceolatus, E. coioides, mangrove snapper Lutjanus argentimaculatus and cobia Rachycentron canadum. Like Trad, Rayong have not been able to spawn their P. maculatus broodstock, despite attempts at hormonal induction of spawning.
There is considerable interest amongst the private sector in Thailand in developing marine finfish hatcheries. There is already considerable production of seabass Lates calcarifer in Thai hatcheries, and many are keen to diversify their production to higher-value species such as groupers. A major constraint to diversification amongst private hatcheries is access to eggs and larvae. Many are now working with the government centers and stations so that when fertilized eggs are available in government facilities, they can obtain them for grouper larviculture trials. The government also provides training and technical support on grouper hatchery technology to the private sector.
Review of Grouper Hatchery Technology
Successful larviculture of groupers has been constrained by generally poor, and irregular, survival. The principal constraints to successful larviculture are: the small gape of the larvae and hence their requirement for small prey at first feed; and the occurrence of high mortality at various stages through the larval rearing phase. This document, prepared by Dr. Mike Rimmer of the Queensland Department of Primary Industry provides a nice review grouper larviculture technology, and summarises the current status of this technology.