Pearl farming in French Polynesia — Economic, scientific and technical challenges

The pearl is one of the few natural gems produced by an animal organism, making it a universal luxury item. However, certain scientific and technical aspects relating to its production remain little-known. In fact, the biological model of the pearl oyster, the flagship bivalve mollusc of Polynesian lagoon environments along with the clam, and the extraordinary zootechnical specificities leading to pearl production constitute particularly extensive fields of investigation. Aquaculture of Pinctada margaritifera (cumingii variety) for black pearl production is an essential activity in French Polynesia. This industry ranks second in French marine aquaculture (after oyster farming) and is the second largest source of revenue for French Polynesia (after tourism), despite the global economic crisis and the structural overproduction it has been experiencing since the 2000s. Pearl farming also plays a vital role in preserving the social fabric by maintaining jobs on the atolls and limiting the exodus to the island of Tahiti. In 2015, the industry counted 536 producers on 26 islands and atolls, covering a total sea surface area of almost 7,800 hectares. P. margaritifera has been the focus of a major research and development effort for over a decade. The resource, less abundant than in the past, and the overproduction of pearls to the detriment of their quality, have made Polynesian stakeholders aware of the need for sustainable management to improve competitiveness on the international market.

This article describes the current state of pearl farming in French Polynesia, and the economic and technical challenges associated with pearl oyster farming. These challenges have led scientists to take a closer look at this emblematic Pacific species, in order to gain a better understanding of the biological processes governing its life cycle. The major physiological functions (nutrition, reproduction, biomineralization) and genetic bases (diversity, selection) for improving the species are described, with a view to producing quality pearls that will no longer rely solely on the passive collection of spat in the natural environment, but on the active production of selected spat - the challenge of sustainable, modern pearl farming.