Andréfouët Serge auteur aut IRD Bouchet N. auteur aut IRD Bruyère O. auteur aut IRD Basset C. auteur aut IRD Bionaz Océane auteur aut IRD Bourgeois B. auteur aut IRD Le Gendre R. auteur aut IRD Liao V. T. auteur aut IRD Marcellino R. auteur aut IRD Trophime T. auteur aut IRD Teaniniuraitemoana V. auteur aut IRD Lo-Yat A. auteur aut IRD text journalArticle eng text/pdf born digital access 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. specialized Pinctada margaritifera Tuamotu Atoll Marine heatwave Aquaculture Stock management POLYNESIE FRANCAISE TUAMOTU GAMBIER 036 034 040 021 222 3 118852 [7 p.] 2026 0025-326X https://www.documentation.ird.fr/hor/fdi:010095485 10.1016/j.marpolbul.2025.118852 0025-326X [F B010095485] https://www.documentation.ird.fr/hor/fdi:010095485 https://www.documentation.ird.fr/intranet/publi/2025-12/010095485.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2025-12-10 2025-12-10 fdi:010095485 fre