Does Size, Growth and Sterility of Triploid Black-Lip Pearl Oysters Result in Better Pearls?

Pearl culture is the most lucrative aquaculture industry in the Pacific Islands, and is an ideal development activity for remote, otherwise-impoverished atolls. Commercial farmers in the U.S.-affiliated Pacific Islands must be hatchery-based, offering opportunity for value-added improvements from triploidy for little additional cost. Techniques for inducing triploidy in Pinctada margaritifera will be developed by refining practices established for edible oysters and other Pinctada species. Cytochalasin B and 6- DMAP will be tested at different timings, exposures, and concentrations. Percentage triploids and survival of larvae and spat will be tracked. This research represents the first known triploidy trials with tropical bivalves and the first use of 6-DMAP in Pinctada. Advantages of triploidy may be more pronounced in tropical animals with extended reproductivity in even faster growth. The widespread use of triploid bivalves suggests a good likelihood of success in Phase I. Phase II efforts will subsequently quantify commercial advantages of triploid pearl oysters. Triploid animals will be seeded, and the success rates and value of pearls from triploid and diploid animals compared. Reduced age at first seeding, increased pearl size, perpetually sterile gonads and avoiding stresses of pre-operative conditioning could all potentially increase pearl production or values and improve farm profitability.