Pearl oyster resources of India

Of the 6 distinct species of Pinctada Roding (Pteridae) viz., Pinctada fucata (Gould), P. margaritifera \n(Linn.), P. chemnitzi (Philippi), P. anomioides (Reeve,) P. sugiUata (Reeve) and P. atropurpurea (Dunker), \nthe first named species is the common pearl oyster of India, occurring on the pearl banks off Tuticorin coast \nin the Gulf of Mannar on the rocky ridges extending all along the coast of the gulf at depths of 15 m-25 m. \nThey are occasionally found in the Palk Bay also in shallower waters lying in loose clusters over a bottom \nof coarse sand grains covered with a matrix of dead shells. In the Gulf of Kutch they are found on the \nintertidal reefs. \nThe pearl fishery in the Gulf of Mannar is unpredictable and it is a question of utilizing the natural resource \nas and when the pearl oyster spat settle down and grow. It is difficult to have effective control over the conditions \naffecting the settlement and growth of the pearl oyster in the natural beds because of their occurrence \nin the open sea. \nFor the purpose of conducting an organized fishery, the population of fishable oysters should be \ndetermined with accuracy. The existing method of estimation of population, the knowledge of the grounds \nand the method of fishing require reorientation. To this end a thorough survey of the areas of oyster settlement \nwas undertaken for a period of 3 years and the grounds charted for the first time by means of direct \nunder-water observations by SCUBA. The outlook for pearl fisheries in the next few years is rather bleak \nat present. \nThe success and failure of the pearl fisheries of the past and the futile attempts made over a number \nof years to watch for the possible settlemenet of the pearl oyster spat show that the only alternative to put \nIndia in the map of pearl producing nations is to resort to pearl culture practices.