The export market for grouper is rapidly increasing specially in Hong Kong, and Singapore, Japan. The biggest challenge in commercial production of grouper fish is the shortage of fingerlings or seed from the wild or hatchery (nurseries).
Because of seed shortage, high market value of this fish have encouraged many countries in Asia including India to initiate research and development programs on grouper breeding and seed production. In India, until now, naturally collected seed from wild waters are serving the purpose.
Grouper fishes are extensively cultured in coastal brackish water ponds and floating, fixed net cages in many south Asian countries. Grouper fishes are naturally low in calories and high in proteins.
Grouper fishes are great source of vitamins and minerals. Local Names of Grouper Fish in India:- Panini been, Caravan (Tamil), McQueen, Álava (Malayalam), MRI menu, Copra, Guru (Kannada), MRI menu (Telugu), Law veto (Bengali).
At this point of time, floating nursery cages with mesh size of 1.5 to 2.0 cm should be made of polyethylene netting supported by wooden frame. These should be kept afloat with metal drums, anchored with concrete blocks and should be stocked with 250 to 600 frying or fingerlings.
The site selected for net-cage culture should be free from predators and strong wind and waves. Construction of Net Cages in Grouper Fish Farming: In net-cage culture, floating cages are built with bamboo poles and polyethylene netting material at 25 to 50 mm diameter.
Generally, these net cages are secured to bamboo poles (raft structure) buy ropes or wires. Buoyancy should be provided by empty plastic gallons attached to the bamboo frames.
Stocking in Grouper Fish Farming: The ideal water temperature for grouper fish farming should range from 27 °C to 30 °C and dissolved oxygen content at 5 mg/l. Commercial fish farmers should go for water testing to maintain optimal techno parameters.
Generally fingerlings of grouper fish with length of 12-15 cm (which are being raised in nurseries) are stocked in net-cages @ 45-50/sq. Yield in Grouper Fish Farming: A net cage of 5 meter x 5 meter x 3 meter (Length, Width and Height of the net cage) can yield up to 600 kg in about 7 months from stocking period assuming that the fishes weighing 600 grams are being harvested (collected).
The optimal techno parameters such as salinity, temperature should be maintained in the pond. The ideal salinity of 330 mg/l and temperature range 16-32 °C should be maintained in pond culture of grouper fish.
When it comes to pond size, generally it varies from 0.2 ha to 0.3 ha in area with a height of 1.5 meter to hold the water level with support of concrete dike. Generally in open pond system, green algae are formed because of sunlight and this needs to be removed frequently.
· A high-value species with great demand in the local and export markets · With prudent pond management, grouper is easier to culture than shrimp, without the attendant disease problems · Wild and captive grouper bloodstock spawn year round, hence, fry are available anytime of the year · The technology of cage culture is relatively cheap and easy to run · Culture can be done in ponds or cages Grouper is a high-value species like tiger shrimp, and with prudent pond management, grouper is easier to culture without the attendant disease problems with prudent pond management.
Shrimp farmers seeking alternative crops have found one in grouper. In addition, grouper fry or “tiny” need to be nursed first and must be regularly sorted and size-graded.
Rectangular net cages supported by bamboo poles and installed inside the pond can serve as nursery. In addition to tilapia, chopped trash fish and/or a formulated feed for carnivorous species may be given to grouper.
Regular monitoring and water changes are part of the pond routine for taking care of the stock. Grouper takes 5-7 months to attain a market-size of 400-800 g. If marketed live, fish farmers need to install temporary nets and tanks where grouper can be held while awaiting buyers and the completion of live packing for transport.
Stock adult tilapia at 5,000 to 10,000 per ha; its fingerlings will later serve as food for grouper. (3) Install 50-watt incandescent, hover-type lamp in every cage, about a foot above the waterline, to attract mys ids, cope pods, and other young fishes and crustaceans at night.
These are live food for the grouper fry, although they may also be given finely-chopped trash fish and/or mys id shrimps or “blaming.” (4) Sort and grade the fry weekly to minimize competition for space and food and prevent cannibalism.
There may be a need to feed more, so give chopped trash fish at the rate of 5% of grouper biomass per day. Place half in a feeding tray for monitoring purposes, and broadcast the rest.
(7) Do the routine pond activities: monitor water parameters (dissolved oxygen, salinity, temperature, depth), change water as the tide dictates, take weight-length measurements of some stock so that feeding can be adjusted. Provide shelters like sawed-off bamboos or PVC pipes in the middle of the net.
Carefully lift the net in early morning when most of the grouper hide themselves there. Take only the biggest fishes and transfer to a pre-installed net that is 4 × 8 × 1.5 m with 1-2 cm mesh size.
Costs-and-Returns Revenue 1,512 kg 280 423,360Variable costs natural food productionChicken manure 1,000 kg 1.00 per kg 1,000For predator eradicationHydrated lime 200 kg 1.50 300Ammonium sulfate (21-0-0) 40 kg 5.00 200Netcages for tiny (2 units, 4 × 2 × 1.5 m)Nylon nets 60 m 30.00 1,800 get cages for harvesting(4 units, 8 × 4 × 1.5 m)Nylon nets (‘A’ size) 224 m 30.00 6,720Bamboo (whole length for horizontal and vertical bracing 4 PCs 50.00 200Monofilament # 180 2 kg 50.00 100Tilapia (100 g) 4,500 PCs 10.00 45,000 Grouper tiny (1 inch) 4,500 PCs 15.00 67,500Trash fish 5,783 kg 10.00 57,830Technician’s salary 8 months 4,000 32,000Power (lights, pump, standby aeration) 20,000Subtotal 232,000Fixed costDepreciation of paddle wheel aerator 5,000Total cost 237,000Net income per run 185,710Net income per year (2 runs per year) 371,420Income tax (35%) 129,997Net income after tax 241,423 Production data Pond area0.9 number of stock4,500 survival rate80%Culture period5 to 7 monthsNumber of cropping per year1Total harvest1,512 average body weight at harvest450 selling priceP280.00/kg Marine cage culture of Grouper Attach floats (plastic drums, barrels) and sinkers or anchors (concrete blocks, etc).
Place hides and shelters inside the net cage; these may be made of sawed bamboo tied in triangular bundles. Install hover-type lamp to attract cope pods and other young fishes and crustaceans; these can be eaten by the grouper.
Biological Features Body elongate, not very compressed; teeth on midsize of lower jaw in 2 rows; nostrils subequal; Serra at corner of properly moderately enlarged; fourth dorsal spine usually longest; membranes of spinors portion of dorsal fin incised; caudal fin rounded; pelvic fins not reaching anus. Light grayish brown dorsally, shading to whitish on side and centrally, with numerous brownish orange or brownish yellow spots the size of pupil or smaller on head and body; 5 slightly diagonal grayish brown bars on head and body which bifurcate centrally, the first 4 extending basally into dorsal fin; brownish orange spots on body tend to be arranged in rows parallel to dark bars, this more evident on smaller than larger fish; large dark grayish brown blotches usually present on head, the most prominent behind eye and on operate; fins whitish to light dusky with brownish orange to brown spots except distally on spinors portion of dorsal fin, caudal fin and pectoral.
Unpublished data record maximum weight as 32 kg and length of male at maturity of 120 cm TL. Historical Background Groupers are generally cultured in floating net cages or earthen ponds, but cage culture is more common in Southeast Asia.
In 1979, the Pelf Station of the Taiwan Fisheries Research Institute (Teri) started artificial propagation by using hormone-inducing technique. E. Coioides is one of the two major cultured groupers in Taiwan P C. The National Mari culture Center, Bahrain has conducted mass fry production trials of this species since 1992.
Grouper pond production is becoming an attractive alternative to intensive shrimp culture in countries where management problems have forced growers to abandon shrimp farming. Main Producer Countries The map shown below is constructed from FAO reported statistics for this species.
Habitat and Biology Epimetheus coincides occurs in the western Indian Ocean from the southern Red Sea to Natal and east to the western Pacific where it is distributed from Ryukyu Islands to New South Wales. It ranges east into Oceania only to Paley in the Northern Hemisphere and Fiji in the Southern.
Orange-spotted groupers inhabit turbid coastal reefs and are often found in brackish water over mud and rubble. Juveniles are common in the shallow waters of estuaries over sand, mud and gravel and among mangroves, feeding on small fish, shrimp, and crabs.
They probably spawn during restricted periods and form aggregations when doing so and the eggs and early larvae are probably pelagic. Seed Supply and Hatchery Techniques Brooders of E. coincides are stocked in separate 50 m 3 tanks.
Most of the brooders are collected from the wild and reared for 1 to 7 years using seawater at a constant temperature of 27-28 °C and 45 ‰, following standard culture methods. The fish are fed with frozen sardines, mackerels, cuttlefish, squids and top-shell clams because these foods have high contents of cholesterol, phospholipids and polyunsaturated fatty acids.
At the National Mari culture Center in Bahrain orange spotted grouper eggs are collect following standard methods. Under a constant temperature regime of 27-28 °C, natural spawning was maintained during a 33-month period between October 1992 and July 1995 and the total number of eggs collected during that period was 279 million.
Daily floating egg rates varied from 5.6 to 69.6 per cent (average 36.8 percent). Whenever brooders do not spawn naturally, mature females and males are selected from bloodstock tanks and injected with Human Chorionic Gonadotropin (HCG) at 700 and 500 IU/kg By respectively.
There were over ten grouper breeder farms raising >10 000 spawners in Southern Taiwan P.C. The eggs are incubated in the same tank with moderate aeration and running water until they hatch.
Newly open-mouth larvae are fed once a day with enriched Fractions plicatilis, Sportier of 160-180 µm size at a density of 5-6 conifers/ml. At TL 6-25 mm, the larvae are also fed enriched Artemis Naples to satiation for 1 to 3 hrs once in the afternoon.
Hatchery reared or wild-caught fry are nursed in tanks or APA nets until they reach 6 cm. Once natural food is abundant, adult tilapia are added at a stocking density of 5 000-10 000/ha to produce fingerlings to serve as live prey for the groupers.
Grouper fingerlings (~6 cm TL) are added at 5 000-10 000/ha at least a month after the release of adult tilapia. Sorting and grading of the fingerlings is carried out weekly to prevent cannibalism and to minimize competition for space and food.
If tilapia fingerlings are not abundant, supplementary feeding is carried out using chopped fish at 5 per cent By/day, half early in the morning and the rest late in the afternoon. Fish are fed with appropriate fresh or frozen chopped fish daily at 10 per cent By or with pelleted feeds 3 per cent By, half early in the morning and half late in the afternoon.
0.5 per cent vitamin and mineral premix is added to the properly thawed trash fish before feeding. Floating net cages should be moved to a new site every 2-3 years of culture to allow deteriorating bottom conditions to recover.
The duration of culture in the grow-out phase is 4-7 months, depending on the preferred size at harvest. Fish are harvested by seine in the early morning or late afternoon.
The water is disturbed (agitated) two hours before harvest to prevent occurrence of rigid muscles in the fish. It is advisable to install 8×2x1.5 or 8×4x1.5 m net cages (25 mm mesh) in the ponds to hold fish temporarily.
The net cage should be inspected for any damage and then lifted slowly from one side to concentrate the fish in one corner. Care must be taken to avoid loss of scales or causing lesions on fish during harvesting.
Handling and Processing Harvested fish are stocked in an aerated conditioning tank. To slow metabolic activity, the water temperature is slowly lowered to 20 °C (2-3 °C/hr) by adding crushed ice in plastic bags or by using cooling pumps.
The bags are packed in styrofoam boxes to which an adequate amount of frozen gel packs, ice bags or frozen water in sealed plastic bottles wrapped in old newspapers is added to keep the temperature low during transportation. This method is suitable for air transport for a period not exceeding 8 hours after packing.
Other large factors are feed (30 percent), followed by administrative expenses and fuel and power requirements for heater/chillers and automatic feeders. Diseases and Control Measures In some cases antibiotics and other pharmaceuticals have been used in treatment but their inclusion in this table does not imply an FAO recommendation. DiseaseAgentTypeSyndromeMeasuresBlister diseaseIridovirus GIV-2VirusHighly localized severe inflammation of epidermal and dermal layer; dermis necrotized, containing exudation and hemorrhagic infiltration at the area of intact layer; presence of icosahedral to round-shaped virions with a diameter of 180-200 nm in infected liver, spleen, kidney and lesions Good prophylaxis & good husbandry conditionsVibriosisVibrio SPP. BacteriaSignificant numbers of monogenean parasites causing gill lesions observedVaccination, good prophylaxis & good husbandry conditionsParasitic InfestationsCryptobia SP, Scythia SP.
Neobenedenia Giselle Graphic SP. Protozoans Monogeneans Isopods and gill lesions; pigmentation; ulceration; skin area haemorrhagesGood prophylaxis & good husbandry conditionsSwim-Bladder SyndromeUndiagnosed or unknownOver-inflation of the swim bladder; loss of buoyancy control Good prophylaxis & good husbandry conditions Popeye (Exopthalmosis)Undiagnosed or unknownExtremely bulging eyes No known successful treatment Suppliers of Pathology Expertise. Aquatic Animal Health Research Institute, Department of Fisheries, Kasetsart University Campus, Natural, Bangkok, Thailand.
National Mari culture Center, Directorate of Marine Resources, Bahrain. Generally, groupers are a popular food fish and it is estimated that the market demand may reach 100 000 tonnes per year in 2020.
Therefore, sustainable aquaculture of groupers and their related species deserves further development. Restaurants display live groupers in Aquarian fitted with water recirculation systems.
As production techniques have improved and off-flavours have been controlled in Taiwan P.C., Singapore and Japan by keeping the market-sized fish in tanks with running water for two days without feeding, orange-spotted groupers have moved into the mainstream seafood markets of developed countries. In highly industrialized countries, small markets for live groupers or frozen imports developed among immigrant communities.
With the appearance of fresh grouper fillets from tropical countries, new markets opened in upper echelon restaurants, casual dining restaurant chains, hypermarkets and discount stores. Virtually all casual dining restaurant chains in the Orient feature groupers, which are an ideal addition to the menu due to their reasonable price, year-round supply, mild, delicious flavor and flexibility in preparation.
China, a major exporter of groupers, has great potential for market development to supply a rapidly growing middle class. Groupers are considered as a high-value species with a high potential for contributing to the economic development of these countries.
The expanding trade in live groupers of various ages and stages, whether for aquaculture or for seafood restaurants, has increased demand since 2006. The development of new faster-growing strains through selective breeding techniques and use of Intensive cost-effective recirculation systems are imperative to increase the production.
The main issues constraining the further development of orange spotted grouper farming include: Although grouper culture is widespread in Asia and the Pacific, its continued development is constrained by the limited availability of fingerlings.
Most economies, except China Taiwan P.C., rely almost totally on wild-caught fry and fingerlings for stocking. The inadequate supply of seed is further aggravated by lack of appropriate handling techniques during collection, transport and storage of collected fish, and sometimes by an unregulated management of the wild stocks.
There is a lack of appropriate techniques for efficient grouper culture to marketable sizes. A major production constraint is heavy mortality of groupers during the collection and culture phases due to handling stress and diseases.
Research to solve these problems is under way in Japan, Taiwan P.C., Thailand and Bahrain. Used during production mainly to prevent and treat bacterial disease, antibiotics are leading to the development of antibiotic-resistant bacteria that are pathogenic to humans.
The development of antibiotic resistance by pathogenic bacteria is considered to be one of the most serious risks to human health at the global level. Many countries around the world have introduced, changed or tightened national regulations on the use of antibiotics, in general and within the aquaculture sector.
Integrated efforts could help to explain the development of intensive productions systems and answer questions raised by the public. Thus, they are the most suitable people to interact with farm operatives and government inspectors in examining the animals and deciding whether they are showing signs of good health and well-being.
The demand for wild seed has led to unsustainable and illegal practices such as the use of cyanide to capture large numbers of seed with relatively low investment in time and effort. Grouper fisheries that are based on illegal or destructive fishing practices underline the urgent need for habitat protection and sustainable utilization of natural resources.
Artificial propagation of the grouper, Epimetheus skills at the marine finish hatchery in Tanning Doming, Terengganu, Malaysia. In: W. Fischer & G. Bianchi (eds), FAO Species Identification Sheets, Western Indian Ocean.
Tan (eds), Proceedings of the Third Asian Fisheries Forum, 26-30 October 1992, Singapore, pp. Hatchery production of grouper, Epimetheus coincides, and rabbit fish, Signs canaliculatus, at the National Mari culture Center, Bahrain: 1995.
National Mari culture Center, Directorate of Fisheries, Ministry of Works & Agriculture, State of Bahrain. Hatchery production of the grouper, Epimetheus coincides, at the National Mari culture Center, Bahrain: 1993-1994.
National Mari culture Center, Directorate of Fisheries, Ministry of Works & Agriculture, State of Bahrain. Sexual maturation, length and age in some species of Kuwait fish related to their suitability for aquaculture.
Revision of Indo-Pacific groupers (Performed: Serranidae: Epinephrine), with descriptions of five new species. Aquaculture Department, Southeast Asian Fisheries Development Center, Manila, Philippines.