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21.2.2 Pearly oyster spat collection
Collection of pearl oyster spat from the natural beds is not always dependaple, owing to their irregular production. Therefore setting up of artificial spat collectors is recommended in the farm area for the spats to attach in large numbers, especially during the peak spawning season, Keeping the spat collectors only during peak season of their breeding will prevent the spat collectors becoming fouled with barnacles and other organisms. There are several practices for spat collection of different species of oysters in different parts of the world. In the eest coast of India lime coated- semi cylindrical tiles are used to collect spat. Strings of scallop or other oyster shells can also be used for the spat collection. In Japan, long lines with leaves and twigs are used as spat collectors. Shells of abalones, oysters and scallops in strings are suspended from rafts just below the surface to about 3 m depth for collecting the spat of pearl oyster. Nylon ropes are used for collecting spat of pearl oysters at Vizhingam. |