 | Lates calcarifer |
CULTURE PRACTICES
Seabass fingerlings occur in tidal creeks and intertidal pools. They are carnivorous and highly predatory, feeding mainly on fish, crustaceans, snails and worms. Fry are available during May-October in the Hoogly-Maldah estuarine system in West Bengal and Chilka Lake during July-August. Intertidal pools with dense grass vegetation form the main source of collection areas in the Sunderbans. A survey conducted by the Central Inland Fisheries Research Institute on the production potential has indicated that 3,000 MT of finfish, including seabass, are annually produced from about 150 bheries. The production from these bheries varied from 325 to 2,325 kg/ha/yr. The yield from experimental fish ponds at the Kakdwip Fish Farm, West Bengal is 3,350 kg/ha/yr. Seabass fry are also collected manually. Hapa nets is one kind of gear commonly operated in sheltered areas at the end of high tide while shooting nets are operated in the intertidal zones of the creeks at Kakdwip, West Bengal. Although seabass culture has not yet developed into a commercial scale it is receiving considerable attention, particularly by a number of research institutes.
PRODUCTION
HISTORY
In India, traditional culture of seabass in large impoundments known as “bheries” along the intertidal zone of the Hoogly-Maldah (West Bengal) estuarine systems has been carried out since 1829. The tidal amplitude in this area ranges between 1.8 and 4.6 m. Generally from March to September seabass and other finfish fingerlings are drawn into the impoundments at high tide. The trapped fingerlings are allowed to grow for 8–9 months until they have attain a marketable size. In Sunderbans, about 0.79 million hectares are suitable for seabass farming.
TOTAL REGIONAL PRODUCTION
STATUS OF CULTURE
| TOPIC | SPECIES |  |
| Lates calcarifer | ||
| Source of seed | Wild | |
| Culture method | Pond | |
| Yield/ha | 325–3,350 kg | |
| Market | Domestic | |
| Production area | 20,000 ha | |
| Status of culture | Developed | |
| Major constraints | Limited seed supply Limited suitable areas | KEY MAP |
 | Epinephelus tauvina |
CULTURE PRACTICES
The cages which are used for the experimental culture of the grouper are rectangular with a dimension of 1.5×1×1 m. The frames are made of palmyra wood while all the sides are covered with palmyra leaf stalks closely nailed together. The cages are placed on the sea bottom and secured to casuarina poles at a depth of about 0.75 m. A concrete block, usually tied to the bottom of each cage, serves as anchor and keeps the cage into position. Grouper fingerlings with an average length of 24 cm (234 g) grew to about 35 cm (758 g) in six months. Although the production of groupers from the experimental cages has been negligible, this culture practice shows some promise, particularly in the shallow coastal waters of India. Although the early attempts to culture this estuarine finfish date back two decades ago, little progress has been made. Major constraints to the development of this seafarming activity is the limited supply of fingerlings and lack of culture know-how and trained personnel. Although grouper culture may become an important activity in the future, considerable research is required.
PRODUCTION
HISTORY
In India, experimental cage culture of the estuarine grouper Epinephelus tauvina was first carried out by Central Marine Fisheries Research Institute (CMFRI) in the late 70s at Mandapam in Palk Bay (Tamil Nadu). At present, no operational culture activity exists, but considerable attention is given to the development of suitable culture techniques, including methods to collect wild fry from coastal waters. Potential culture sites have been identified all along the Indian coastline. The production in 1987 of 4,619 MT came from capture fisheries.
TOTAL REGIONAL PRODUCTION
STATUS OF CULTURE
| TOPIC | SPECIES |  |
| Epinephelus tauvina | ||
| Source of seed | Wild | |
| Culture method | Cage | |
| Yield/ha | NA | |
| Market | Domestic | |
| Production area | NA | |
| Status of culture | Experimental | |
| Major constraints | Limited seed supply Limited suitable areas | KEY MAP |
 | Crassostrea madrasensis |
CULTURE PRACTICES
Small scale bottom culture of oysters by transplanting spat from natural beds to shallow areas of convenience has been practiced for some time. Oysters are cultured in intertidal regions, bays and estuaries. Apart from bottom culture, the rack method has been developed and practiced. This method is employed in shallow coastal waters. Each rack is composed of two rows of six poles (2.4 m in length) driven into the muddy bottom at an interval of 2 m apart. Each set of six poles are fixed together by a long pole placed horizontally on top of them; the two rows are connected to one another by a series of short poles placed horizontally between the two long poles. This rack system, which usually covers an area of 25 sq. m., constitutes a suitable platform for suspending the oyster trays. Each rack can accommodate 20 rectangular trays which have a holding capacity of 3,000–4,000 oysters. Other culture techniques have been developed, such as pole and long-line culture. Oyster spat are collected using a variety of cultches such as oyster shells, coconut shells, PVC tubes and lime coated tiles. Hatchery techniques for producing oyster spat have been developed at Tuticorin.
PRODUCTION
HISTORY
A number of oysters occurs in Indian waters; the native Indian oyster (Crassostrea madrasensis) is the one which is commercially exploited on a large scale. It occurs throughout the coast of India and dominates the entire east coast and Kerala. Oyster culture in India is not as well developed as in other Indo-Pacific countries, however it has received considerable attention within the last decade. The Central Marine Fisheries Research Institute (CMFRI) is the main institution involved with bivalve culture. Research to promote and improve oyster culture in India is ongoing.
TOTAL REGIONAL PRODUCTION
STATUS OF CULTURE
| TOPIC | SPECIES |  |
| Crassostrea madrasensis | ||
| Source of seed | Wild and hatchery | |
| Culture method | Bottom, Intertidal, suspended | |
| Yield/ha | NA | |
| Market | Domestic | |
| Production area | ||
| Status of culture | Developing | |
| Major constraints | Loack of trainned personnel Marketing (low market demand) Limited seed supply | KEY MAP |
 | Pinctada fucata Pinctada margaritifera |
CULTURE PRACTICES
Although six species of pearl oysters occur in the Indian waters, only Pinctada fucata can produce high quality pearls. Mother pearl oysters are obtained either from the natural pearl banks in the Gulf of Mannar at depths of 12–25 m or from hatchery produced spat. The pearl oysters are grown in box-type cages which are hung from wooden rafts. A graft piece of mantle followed by a spherical shell bead nucleus are implanted in the gonads of pearl oyster. Newly operated oysters are reared indoors for 3–4 days until the effect of narcotization wears off, and later in cages suspended in areas of high phytoplankton production. Multiple implantation of nuclei is done to enhance the rate of pearl production. The pearl oysters are reared at a depth of 5 metres. Significant deposition of nacre takes place in three months. Some 1–5 pearls can be produced in a single oyster depending on its size. Pearl harvest is carried out during the cold season. A 6×5 m raft accommodates about 100 cages each containing about 100 oysters of 45–55 mm length. Among the surviving oysters about 60% produce pearls. The quality of pearls produced varies considerably.
PRODUCTION
HISTORY
In India pearl culture trials were first attempted in the 30s by the Fisheries Department at Krusadai Island in the Gulf of Mannar. However, only a few blister pearls were produced. In 1972 the Central Marine Fisheries Research Institute (CMFRI) started a research project on pearl culture at Tuticorin. By implanting spherical shell bead and a piece of mantle in the gonadal part of the pearl oysters and careful rearing of the operated oysters on rafts, perfectly spherical pearls were first produced in July 1973. Hatchery techniques for producing pearl oyster seed have been developed.
TOTAL REGIONAL PRODUCTION
STATUS OF CULTURE
| TOPIC | SPECIES |  |
| Pinctada fucata | ||
| Source of seed | Wild and artificial | |
| Culture method | Raft | |
| Yield/ha | 60% of implantations | |
| Market | Domestic | |
| Production area | Few experimental rafts | |
| Status of culture | Experimental | |
| Major constraints | Production management | KEY MAP |
 | Perna viridis |
CULTURE PRACTICES
Mussel raft, pole and bag culture have all been attempted in India. The rafts are usually fabricated out of casuarina poles covering an area of 25 sq. m., however larger ones measuring 8×8 m have also been used. The rafts are buoyed by a sufficient number of oil drums and kept in place by anchors weighing 60 kg each. The mussel spats are collected from the wild, cleaned of the fouling organisms and seeded to coir ropes with the help of a strip of cotton webbing about 6 m long and 20 cm wide. The two ends of the rope are firmly tied and a stone weighing about 2 kg is tied to one end so that each rope hangs vertically from the raft. One 5×5 m raft can accommodate 50 ropes each measuring 6 m in length. With this culture method the mussel attain the commercial size of about 6 cm in 6–8 months. Pole and bag culture of mussels have been attempted in sheltered areas along the Indian coast. In the former method the mussel spat are fixed on teakwood poles by using cotton webbing which are planted in protected lagoons. In the bag method the seeds are reared in bags made of synthetic webbing which are fixed on racks 5×5 m in dimension.
PRODUCTION
HISTORY
Culture of the green mussel, Perna viridis, was first attempted in the early 1970's by the Central Marine Fisheries Research Institute (CMFRI). Rearing trials were carried out in the inshore waters at Vizhinjam, Southern Kerala, using the hanging rope method. This was followed by open sea farming about 2 km from the shoreline off the coasts of Calicut and Karwar. The green mussel was successfully cultured by the Institute in sheltered areas at Muttukadu, south of Madras. Hatchery techniques have also been developed by CMFRI at Madras. Mussel farming is not practiced commercially in the country.
TOTAL REGIONAL PRODUCTION
STATUS OF CULTURE
| TOPIC | SPECIES |  | ||
| Perna viridis | ||||
| Source of seed | Wild | |||
| Culture method | Raft | Pole | Rack | |
| Yield/ha | 4–12 kg/m 5 months | 10 kg/pole 6 months | 15 kg/bag 6 months | |
| Market | Domestic | |||
| Production area | Few rafts | 80 poles | two racks | |
| Status of culture | Experimental | |||
| Major constraints | Low market demand Need to improve culture technology | KEY MAP | ||
 | Perna indica |
CULTURE PRACTICES
Square and rectangular rafts measuring 6×6 m or 5×4 m, respectively, have been used to experimentally culture brown mussels in Vizhinjam Bay. The rafts are made of teak wood and bamboo poles lashed by coir or nylon rope 5–7 mm thick. Metal drums of 200-litre capacity, treated with anticorrosive paints, are used as floats. The raft is moored by anchors with sufficient length of anchor chain to allow for the tidal range. Mussel seeds are collected from natural beds using iron chisels. Split nylon ropes, roof tiles, strings of coconut shells, iron hapas covered with nylon screen and split old bamboo poles are also used as mussel collectors. Natural mussel spat of 24–29 mm in length are seeded on 12–14 mm thick coconut or synthetic ropes in October and November. The mussel ropes are usually 6 m long and suspended from the raft. Periodic cleaning and thinning of the ropes eliminates fouling organisms and avoids overcrowding of mussels. The cultured mussels attain the marketable size of 60–65 mm in 8 months. The average weight of mussel seed/m of rope ranges from 1.5–2 kg. They attain 10–15 kg at the end of the culture period.
PRODUCTION
HISTORY
Experimental culture of the brown mussel Perna indica has been recently conducted on rafts by Central Marine Fisheries Research Institute (CMFRI) at Vizhinjam, on the Southwest coast of India. Farming was done in Vizhinjam Bay which has a water depth of 10–15 m and where there is a good settlement of wild mussel seed on intertidal rocks. Open sea farming has also been carried out outside Vizhinjam Bay. Collection of spat is done with the use of numerous collectors, although seed supply is still the major constraint to the development of this seafarming activity.
TOTAL REGIONAL PRODUCTION
STATUS OF CULTURE
| TOPIC | SPECIES |  |
| Perna indica | ||
| Source of seed | Wild | |
| Culture method | Raft | |
| Yield/ha | 10–15 kg/m rope/7 months | |
| Market | Domestic | |
| Production area | Few rafts | |
| Status of culture | Experimental | |
| Major constraints | Limited seed supply | KEY MAP |
 | Anadara granosa |
CULTURE PRACTICES
Anadara granosa are experimentally cultured in Kakinada Bay (Andhra Pradesh) in muddy areas with suitable environmental parameters for the growth of the species. Natural spats with an average length of 24 mm are stocked at densities of 140–230/sq.m. In the pen culture method, split bamboo screens interlaced with hemp twine are used for the construction of the enclosures. The function of such screens is to protect the fragile spat from being preyed upon by bottom feeding organisms. Culture period is 5 months and the survival rate ranges from 83–86%. Yields from 38–41 MT per hectare have been obtain in areas protected by the bamboo screens. Although cockle culture is not commercially practiced, a number of potential sites have been identified along the coast of Andhra Pradesh and Tamil Nadu. Almost all of the cockle production in India comes from harvesting of natural beds. In 1987 about 30,000 MT were produced.
PRODUCTION
HISTORY
Experimental culture of the blood cockle, Anadara granosa, was first conducted by the Central Marine Fisheries Research Institute (CMFRI) in Kakinada Bay during the period 1979–82. The cockle spat were collected from natural spatfall areas in the bay. Farming was carried out by sowing the seeds in selected bottoms, with and without pen closure. Good survival rate and production output were obtained. Cockles can be easily cultured with a low initial capital investment and are highly valued as an export species. One major constraint to the development of this seafarming activity is the limited supply of seed.
TOTAL REGIONAL PRODUCTION
STATUS OF CULTURE
| TOPIC | SPECIES |  |
| Anadara granosa | ||
| Source of seed | Wild | |
| Culture method | Bottom | |
| Yield/ha | 38–41 MT/ha/5–7 months in enclosure | |
| Market | Domestic | |
| Production area | 0.2 ha | |
| Status of culture | Experimental | |
| Major constraints | Limited seed supply | KEY MAP |
 | Gracilaria edulis |
CULTURE PRACTICES
The Central Marine Fisheries Research Institute (CMFRI) has experimentally cultured Gracilaria edulis in the inshore waters of Mandapam (Gulf of Mannar). Clean fragments of the seaweed (about 4 cm in length) are taken from the apical parts of adult specimens and inserted in the twist of a coir rope frame. The coir nets measuring 4×2 or 5×2 m are then fixed horizontally above the sea bottom at sudtidal level in order to keep them permanently submerged. About 2.5 kg of seed material is fixed on each rope frame. Within two months it becomes covered with a profuse growth of the cultured algae. Harvesting is usually carried out in 2–2.5 months by cutting off the plants and leaving the basal parts for further growth. One kg seed material of G. edulis yields an average 3 kg/sq.m. of net after 60 days growth. The seed material from natural beds is available in significant quantities in the Gulf of Mannar, Pamban, Rameswaram and Mandapam. The suitable seasons for carrying out the culture operations are October to April in the Gulf of Mannar and May to September in Palk Bay. The production in 1987 which amounted to about 2,000 MT dry weight came from harvesting of natural beds.
PRODUCTION
HISTORY
The need for culture of marine seaweeds in India has been recognized since the early 1960's. Seaweeds have been cultivated on an experimental scale using two methods: vegetative propagation of seaweed fragments and by rearing gametes, oospores, tetraspores and carpospores. The vegetative method is an easy and inexpensive method resulting in quick growth of the algae. Experimental culture trials by this method have been conducted successfully by central Marine Fisheries Research Institute (CMFRI), Central Salt and Marine Chemicals Research Institute (CSMCRI) and National Institute of Oceanography (NIO).
TOTAL REGIONAL PRODUCTION
STATUS OF CULTURE
| TOPIC | SPECIES |  |
| Gracilaria edulis | ||
| Source of seed | Wild | |
| Culture method | Bottom monoline (coconut rope) | |
| Yield/ha | 3 kg/m2/60 days | |
| Market | Domestic | |
| Production area | 0.2 ha | |
| Status of culture | Experimental | |
| Major constraints | Turbidity Predation | KEY MAP |
 | Holothuria scabra |
CULTURE PRACTICES
In the experimental culture of Holothuria scabra adult specimens of both sex are collected from the sea and stocked in fibreglass tanks. The tanks have a sandy-muddy substratum with a large component of organic detritus on which the broodstock feeds on. The substratum is replaced every few days. Male specimens are induced to spawn when transferred to a 70-litre tank with a water temperature 5–10 degrees centigrade above ambient water temperature. The spermatozoa released in the water stimulates the females which soon begin to spawn. Fertilized eggs develop into the dipleurula, auricularia, doliolaria and pentactula stages and on to the juvenile stage. The auricularia larvae actively feed on phytoplankton (Isochrysis galbana) while the pentactula are fed on powdered Ulva and Sargassum. The juveniles are broadcast in enclosed coastal areas until they reach marketable size. After harvesting the holothurians are cleaned, degutted, boiled and buried in damp sand pits for further cleaning. The holothurians are removed from the pits after 15–18 hours, boiled and dried until they retain only 8– 10% of the body moisture.
PRODUCTION
HISTORY
Exports of beche-de-mer from India to the Far East has been a profitable activity for many years. As a result, overfishing is becoming apparent in certain areas. In order to protect the resource the Central Marine Fisheries Research Institute (CMFRI) has been encouraging conservation and management measures. In addition, experimental culture of the so called sand fish (Holothuria (Metriatyla) scabra) was first carried out by the CMFRI at Tuticorin in 1988. This species was successfully induced to spawn and reared to the juvenile stage in the laboratory.
TOTAL REGIONAL PRODUCTION
STATUS OF CULTURE
| TOPIC | SPECIES |  |
| Holothuria scabra | ||
| Source of seed | Artificial | |
| Culture method | Bottom (enclosed areas) | |
| Yield/ha | NA | |
| Market | Export | |
| Production area | Experimental area | |
| Status of culture | Experimental | |
| Major constaints | Refinement of culture techniques | KEY MAP |
