Photo credit: Han Huong (Vietnam)
Review: Abdel Rahman El Gamal (Founder of the website)
Cage culture of grouper (Epinephelus sp.) in Vietnam has witnessed a rapid expansion throughout the 1990s in a number of provinces including Khanh Hoa in the south central of Vietnam whereas fixed and floating cages have been used. Grouper is a valuable species especially in Asian markets. The importance of grouper culture resulted from the increasing demand as well as the depleting wild fish populations.
Typically, cages range in volume between 10-30 cubic meters, constructed with synthetic netting stretched over bamboo frames, hanging from wooden stakes driven into the seabed or floating rafts anchored in the seabed. It is common to see families –who usually own and operate cages- group their cages into clusters for management and security purposes.
Almost all seed supplied to the cages come from the wild whereas seed are harvested by local fishermen who might supply it directly to cage farmers or carry out some nursing to reach the 10-15 cm which is the preferred size to be stocked in cages. In regard to feeding, only whole locally caught fresh trash fish are used for feeding grouper.
The significant development of grouper culture in Vietnam has caused a pressure on wild caught fry and fingerlings of grouper. Similarly, the trash fish which seems abundant at the present time may not remain that abundant in the future. Therefore, future development of grouper farming will certainly require investment in hatcheries and nurseries to supply seed. In addition, there is a need to explore cost-effective alternatives to trash fish for feed.