The Basic Methods of Pearl Farming: A Layman's Manual - CTSA

Basic Methods of Pearl FarmingFigure 16. Black-lip pearl oyster spat. Note thegrowth processes with broad tips-a distinguishingcharacteristic of this species. Related speciesusually have growth processes with more pointedends.When spat appear on collectorsWhen spat are large enough to be identified, you have two choices of what to do next.1) Cut (never pull) the spat off the collectors and keep them in lantern baskets.The lantern baskets have the advantage of protecting the spat from predators and fewer spat will be lostdue to falling off the spat collectors. This option is more costly and requires more maintenance. Thelantern baskets should be cleaned and inspected weekly for the presence of predators such as snails andcrabs.2) Leave the spat on the collectors until they are large enough to drill and hang onchaplets.Spat are large enough to be drilled when they reach a size of 4 inches (8-10 cm), or are large enough toput in panels. If you wait to remove them from the collectors until after the spat are larger, be preparedto add more floats to the spat collector lines since they will become very heavy and sink. In addition,you may lose some spat to predators this way to predators or they may fall off the collector. However,if spat settlement is heavy, this option is less expensive and more efficient.After removing the spat, the collectors can be dried for a few weeks, cleaned and reused.Caring for the spatSpat are like all young animals; they are weak and easy to damage.Spat should be handled gently at all times, and never more than necessary. Most importantly, never pullthe byssal threads out of a spat, as this will kill them. Always gently cut the byssal threads.Page 44