Aquaculture of high-value marine finfish species continues to develop rapidly in Southeast Asia. Many groupers (members of the Family Serranidae, Subfamily Epinephelinae) bring high prices (up to US$70/kg wholesale) in the live markets of Hong Kong and southern China (McGilvray and Chan 2001).
Increasing market demand and the real or perceived profitability of the live reef food fish trade has led to many Southeast Asian and Pacific countries focussing on supplying this apparently lucrative trade through wild capture fisheries and aquaculture (Sadovy et al. 2003).
Worldwide, most grouper aquaculture production is from Southeast Asia. Based on FAO data, Taiwan and Indonesia are the major producers of farmed grouper, followed by Thailand and Malaysia (Table 1).
However, unreported production may be substantial. Mainland China produced an estimated 8256 t of groupers in 1997 according to unofficial reports (NACA/TNC 1998), and production is likely to have increased substantially since then.
Vietnam produced an estimated 2600 t of marine fish in 2001, of which a high proportion was cultured groupers (Le 2002). Based on these estimates, the regional total production of groupers through aquaculture in 2001 may have been more than 23,000 t and valued at around US$160 million.
Despite the continuing expansion of grouper aquaculture in the Asia-Pacific region, there remain several important constraints to the sustainable development of this industry sector. Foremost amongst these is the limited availability of fingerlings. Grouper aquaculture remains heavily dependent on the capture and grow-out of wild-caught juvenile fish; around 70–85% of cultured groupers are grown out from wild-caught fry (Sadovy et al. 2003).
Epinephelus coioides is a mainstay of the live reef food fish trade and is now widely cultured throughout Southeast Asia. It is found from the Red Sea south to at least Durban and east to the western Pacific, where it ranges from the Ryukyu Islands to Australia and eastwards to Palau and Fiji.
Other localities include the Persian Gulf, India, Reunion, Mauritius, Andaman Islands, Singapore, Hong Kong, Taiwan and the Philippines, and it has been reported from the Mediterranean coast of Israel.
This species is frequently misidentified in the aquaculture literature as E. tauvina or E. malabaricus and is sometimes incorrectly named E. suillis (a synonym). E. coioides is widely known as green grouper, estuary cod in Australia, kerapu lumpur in Indonesia, and lapu-lapu in the Philippines.
In addition, there is a recognised need to replace the widespread use of ‘trash’ fish as a feed source for groupers with compounded diets, as has been done for other marine finfish species such as barramundi/seabass ( Lates calcarifer ) and milkfish ( Chanos chanos ).
Marine finfish aquaculture is an important contributor to the economies of coastal communities in the Asia-Pacific region, and aquaculture of high-value species such as groupers provides greater economic benefits to farmers than aquaculture of lower-value species such as milkfish (Yap 2002). Consequently, the development of sustainable grouper aquaculture can potentially provide widespread benefits to coastal communities in the Asia-Pacific region.
The results described in this publication are the outcomes of a four-year research and development project funded by the Australian Centre for International Agricultural Research (ACIAR), involving collaborative research by institutions in Australia, the Philippines, Indonesia and the Asia-Pacific region.
The project targeted two of the major production technology constraints for grouper aquaculture: increasing fingerling supply by improving hatchery production technology; and determining the requirements of juvenile groupers for critically-important nutrients, which is a prerequisite for the development of practical compounded diets to replace the feeding of ‘trash’ fish. In addition, the project provided a regional structure to coordinate and promote collaboration in grouper aquaculture research, development and extension activities to better utilise the existing institutional efforts in the Asia-Pacific region.
Author:
M.A. Rimmer
