Influence of production method on the profitability of mabé pearl farming using traditional and research-informed nucleus implanting practices with the winged pearl oyster, Pteria penguin

Abstract Mabe pearl culture has become a significant addition to traditional rural livelihood activities in Tonga and in other south Pacific countries. Mabe pearl culture is a low-cost, low-tech alternative to round pearl culture, can be undertaken by local people with minimal training, and has considerable potential for value adding through production of jewellery and handicraft items. Mabe pearls are produced by attaching hemispherical nuclei to the inner shell surface of pearl oysters where subsequent coverage with nacre (mother of pearl) produces commercial pearls after a culture period of around 12 months. Traditionally, local mabe pearl farmers attempt to maximise pearl output by implanting four high-profile nuclei into each oyster. Recent research has indicated that fewer nuclei, and those with lower profile, may improve the overall quality of resulting mabe pearls and this has been adopted as best-practice by Tongan mabe pearl farmers. This study reports an economic comparison of these two nucleus implanting arrangements. Results showed that annual returns were not dissimilar with the traditional implanting method (four high-profile nuclei) generating USD 6977 per annum, while the recommended best-practice method (two low-profile, one high-profile nuclei) generated USD 6795 per annum. While the traditional method may generate potentially higher annual returns, there are two key considerations that favour the best-practice method: (1) reduced labour commitment that provides opportunity to engage in other livelihood activities; and (2) the production of a higher grade of pearls is more supportive of developing high value export markets for Tongan mabe pearls.