Decline and status of natural pearl oyster (Pinctada margaritifera) stocks in two French Polynesia black pearl farming lagoons

2026

Article référencé dans le Web of Science WOS:001606023700002

Andréfouët Serge, Bouchet N., Bruyère O., Basset C., Bionaz Océane, Bourgeois B., Le Gendre R., Liao V. T., Marcellino R., Trophime T., Teaniniuraitemoana V., Lo-Yat A.

Marine Pollution Bulletin, 2026, 222 (3), p. 118852 [7 p.] ISSN 0025-326X

In French Polynesia, the pearl oyster Pinctada margaritifera has allowed black pearl production since four decades. The production remains dependent on spat collections in atoll lagoons. Through their reproduction, the oysters of the natural stock are contributors of spats, and possibly the only contributor. After an assessment in 2013, natural stocks of Takaroa and Ahe atolls were revisited in 2022 and 2024 respectively. Results show a sharp decrease of the densities at almost all field sites, with average lagoon-wide losses by factors of 2.35 and 8.87 for Ahe and Takaroa respectively. Takaroa was impacted in 2013-2014 by a massive harmful phytoplanktonic bloom and the decrease was expected, but the population size structure shows recruitment, providing hope for farmers. Conversely, the reason for Ahe's population decline remains unclear. Likely suspects are increased periods of high temperature and predation that affect oysters at their different life stages and impact recruitment and survival.

Sciences du milieu [021] ; Limnologie biologique / Océanographie biologique [034] ; Ecologie, systèmes aquatiques [036] ; Ressources halieutiques [040]

POLYNESIE FRANCAISE ; TUAMOTU GAMBIER

Fonds IRD [F B010095485]

fdi:010095485