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Free download of : Maual on Pearl Oyster Seed Production , Farming and Pearl Culture
The pearl oysters belong to the genus Pinctada (Roding) come under the family Pteriidae. They occur in almost all the seas of the tropical and sub tropical belt. They inhabit the seabottom from low tide level to depths down to 80m. Although 28 species of pearl oysters are reported.only 3 species have been found to produce pearls of gem quality and have commercial value. They are Pinctada maxima (Jameson), P. margaritifera (Linnaeus) and P.fucata (Gould). The pearl oysters occur in the Persian Gulf (Bahrain,Kuwait,Dubai,Muscat and Bushira), Red sea (Farasan Islands, South of Sabia and Jidda, West of Mecca and Sudan),Philippines,
Japan, China, Korea, Myanmar, Indonesia, Papua New Guinea, French Polynesia, Cook Islands, Australia, Gulf of California, Mexico, Panama and Venezuela.
Distribution in Indian waters In Indian waters, they occur in 6 regions namely the Gulf of Mannar, Palk Bay, off Trivandrum, the Andaman and Lakshadweep Islands, and the Gulf of Kutch. Of these, the Gulf of Mannar and Gulf of Kutch are the most productive regions where pearl oysters occur in large numbers.Six species of pearl oysters occur in Indian waters. They are Pinctada fucata (Gould), P.margaritifera (Linnaeus), P.chemnitzii (Philippi), P.sugillata (Reeve), P.anomioides (Reeve) and JP.atropurpurea (Dunker). Of these, P.fucata occurs extensively in the beds of Gulf of Mannar and to a less extent in the Gulf of Kutch. These two regions had
contributed to the pearl fisheries in the past. The black-lip pearl oyster P.margaritifera, occurs in stray numbers in some pockets of Andaman and Nicobar Islands. Here they are fished more for the shells than for their pearls. In the Palk Bay, P.chemnitzii are found on coarse sandy mud bottom. In Lakshadweep, settlement of spat of P.anomioides has been observed on the ridges of the rocks and corals in some islands. In the south-west coast of India, at Vizhinjam.the spat of P.fucata were collected from mussel culture ropes ……