Shrimp Farming:

The technical improvements made in shrimp farming in many parts of the world paved the way to increase shrimp farming through aquaculture by adopting extensive, modified extensive and semi intensive systems of shrimp farming in the areas where environmental conditions are well suited. Tamil Nadu is endowed with rich natural resources such as coastal zones in the form of brackish water / estuaries for shrimp culture. The brackish water resources of Tamil Nadu is about 56,000 ha. in which 18,000 ha. are identified as potential areas for farming. At present shrimp aquaculture has been developed in 12 maritime district of Tamil Nadu in about 4455 ha. The tiger shrimp (P.monodon) and white shrimp (P.indicus) are the most common species cultured in shrimp ponds. The farmers are encouraged to adopt traditional and extensive farming methods for sustainable aquaculture.

Sea Weed Farming

Sea Weeds are simple plants grown in the Shallow waters of the seas. These are popularly called "Sea Vegetables". There is a potential markets for the Sea Weeds. They can be easily cultivated with the help of floating rafts in the near shore areas. The Palk Bay and Gulf of Mannar area are abundant in Seaweeds. The Gulf of Mannar area is well suited for Seaweed farming. The seaweeds are the only source for the production of phytochemicals such as agar, carrageenan and algin. Seaweeds are divided into Green, Brown, Red and Bluegreen algae based on the type of pigments, external and internal structures.

The dominant varieties of Seaweeds are:
Gracilaria edulis, Gelidiellaacerosa, Sargassum, Turbinaria, Hypnea, Laurencia species.

Seaweed centres along the southeast coast of Tamilnadu:
1.Rameswaram, 2. Pamban, 3.Vedalai, 4. Pudumadam, 5.Periapattanam, 6.Kalimankundu, 7. Kilakarai, 8.Ervadi, 9. Valinokkam, 10.Kanyakumari area.

There are two methods of cultivation of seaweeds.
• 1. By means of vegetative propagation.
• 2.Spores such as swarmers.

Mussel, Clam and Oyster Farming:

Mussel and Oysters are valuable shell fish resources of Tamilnadu. The Green Mussel Pernaviridis is predominant in Tamilnadu. Open seas and estuarine areas free from strong wave action for idle for Mussel culture. Clams are the most important among bivalve resources. Commercially exploited and cultivable clams are:-Meretrixcasta, M.Meretrix, Anadaragranosa. Rich beds of clams exist in Pulicat lake, Vellar, Athankarai and Punnakayal estuaries along east coast. There is great demand for clam meat, adductor mussle of Giant clam.

Oysters inhabit littoral and shallow sub tidal areas. They occur in wide range of in eco-systems including the coral reefs, mangroves and rocky shores. The dominant species are:-Crassostreamadrasensis, C.gryphoides, C.rivularis. Oyster reefs are considered as essential fish habitat. Oyster farming technology is a simple and easily adaptable technique. The different farming methods are:- Rack and ren method, Rack and tray method.

Pearl Oyster Farming

The Pearl Oysters (Pinctadasp) occur in the Gulf of Mannar, Palk Bay areas. Six species of Pearl Oysters occur in Tamil Nadu. Tuticorin Coast in Tamilnadu is well suited for Pearl Oyster farming. This farming technology can be done by Raft culture, Rack culture and Long line culture.

The natural pearls Oysters harvested from Gulf of Mannar region is held in high esteem due to its lustre. The pearls from Gulf of Mannar area is regarded as orien pearls.

Marine Fin Fish Culture

Cobia, Sea bass and Pompano are the most favoured candidate species for Fin fish farming. These fishes are highly priced marine food fishes having tender and tasty meat having good market potential. The enclosed bays, estuaries and shallow coastal waters are well suited for farming. The hatchery technology for seed production of sea bass has been perfected and seed production is not a constraint. The Sea bass can be grown in Cages erected in backwaters.

Crabs and Lobsters Farming

Tamilnadu is one of the leading states in India with tiny Lobster and Crab resources of high commercial value. About 700 tonnes are harvested every year in which nearly 50% are of undersized juveniles varying from 50 grams to 250 grams per piece. Moulted crab otherwise called as water crab does not fetch good market value. Once it reaches to 250 grams size the price variation is double or even triple. Growth rate of crab in cages is encouraging with supplementary feed.

Juvenile lobsters caught from the wild can well be grown to marketable size in cages by giving supplementary feed. The lobster juveniles grow at the rate of 1gram per day. Fibre Glass Reinforced Plastics Cages can be used for fattening of Crabs and Lobsters. Live export of lobsters and crabs fetch high market value.