Green Greasy Grouper, Kerapu Botol, Epinephelus tauvina





Green Greasy Grouper. Photo Credit: Randall, J.E


 Green Greasy Grouper, is among the first species of groupers being cultured in this country. Back in mid of 1970s, the fry of cultured fishes of this species come from the wild. During that period, there is almost no fish nursing activity commercially done in the country. Since we did have abondance of the fry of this species in our water, it were caught and sold to neighbouring countries for nursing until to gain size of 1 inch size or bigger. Most of our cage culture operators during that time have bought the 1 inch to 3 inches fry from neighboring countries and grew them in their cages until they reach the market size of 600 g - 800 g. During that period, the mortality rate of stocked fry were very high especially during 1st week to  3rd weeks from the stocking day. Lack of know-how even on cage culture methodology was rampant among the fish farmers. Since then, many efforts taken by some of the government agencies on cage culturing  and fry nursing techniques to improve the culturing techniques and innovated the nursing techniques in this country. All these efforts although taking times to makes reasonable impacts, but were surely the changing factors of the new development of our aquaculture industry in this country.

Distribution of Green Greasy Grouper. Source: fishbase.org

The green greasy grouper is the native fish for many regions. It is one of  the most wide spread among  groupers species in tropical and sub-tropical waters. It can be found in Indian Ocean,Red Sea, Andaman Sea, Malacca Straits, South China Sea, China Sea, Sulu Sea and Pacific Ocean, ranging from 30°N to 32°S and 29°E to 123°W and always associated with the coral ecology from 1meter to 300 meters. It can grow up to 80 cm length and weight up to 27 kg.



Green greasy grouper's normally found in the coral area. Photo: Mahmud Ismail.

Green Greasy Grouper common being served in our local seafood restaurants. Although not getting high price in the export markets, this species still getting reasonable price locally which make some farmers now keeping some this species in their farming system  to supply to the local live seafood outlets. As our local markets favor slightly small size fishes (600g to 800g each) the farmers find that this species easy to be farmed and within comparatively reasonable farming periods. Since this is a native species to the our waters and with locally produced fry, it having less problems than any species that using imported fry.





Coral Trout, Kerapu Bara, Plectropomus leopardus .


 


Coral Trout, P. leopardus

 

This species already in the Malaysian aquaculture and fisheries industry for quite sometimes, they have been sought after by the fishermen and aqriculturist as well as the seafood restauran operators.  Lately, they are commonly cultured especially in Sabah, Pulau Pinang, Perak, Selangor and Johor. The landing from the wild catches always sporadic all over nation.






Transporting Live Coral Trout in Semporna, Sabah.



This fish getting very good price in local and export markets. In some places in Malaysia, this fish will be caught alive. The off-sizes fishes will be kept  in the cages and be fed with fresh fish until they grow to the market size. Although this method of farming has been debated due to utilisation of natural resources and not that efficient in reducing the pressure on natural stocks plus the usage of food fish to fed the fish, I still consider this method as a value addition process to increase the value of the off-sizes Coral Trout that have been caught by the fishemen.

The commercial farming of this species always using the imported fry from other fry producing nations. There is no report of fry production of this species in Malaysia so far though there could be some unreported productions from the commercial hatcheries.




Distribution of Coral Trout. Source: fishbase.org

 

In the wild, this species always associated with coral areas at the depth of 3m to 100m. It usually can be found from 35°N to 30°S and 99°E to 178°W, from Eastern Indian Ocean to Western Pacific Ocean. The biggest recorded weight was 23.6 kg and with body length 1.2 meters though normally found was around 0.5 kg to 3.5 kg and with body length between 20 cm to 35cm. The longest repoted age of this fish was 26 years. The fish sexually mature at the length of 21-60cm. The adult fish feed on fishes and squids. They are protogynous hermaphrodite (initially as functional females, then turn into functional males at certain age). They normally spawn during new moon phase and having spawning aggregations behaviour during mating process in the reef area.  Their fertilize eggs will float just below the surface of the sea water until hatched. The juveniles of Coral Trout feed on small fishes and crustaceans and normally found in the demersal of shallow coral areas.

In term of price, I saw this species have enjoyed very high price for the last few years with last year highest price of HK$700/Catty and lowest HK$300 and average price of HK$545/Catty making it a very good high value species in HongKong market. The colour of this species also suit to  our Asian taste for happy colours of our foods. Red and golden spotted always associated with good luck and prosperity to us, the unique Asian people.

With good demand and good price, it really supprise to see that this species is not among the popular marine fishes that be able to be reproduced in this country. Perhaps, we do really must strategize our priorities of the targetted species that we must pay attention to. I read an article published in an aquaculture journal back in 2001 that some countries already started producing the fry of this fish way back in 1985.  We hope to see some changes this year and hope there will be some report on the production of this species by Malaysian hatcheries.