As part of WP2 of the MaHeWa project — and specifically Task 2.2, which focuses on the impacts of harmful algal blooms (HAB), including ciguatera — a major new study has just been published in the journal Harmful Algae. Entitled “Gambierdiscus polynesiensis from New Caledonia (South West Pacific Ocean): Morpho-molecular characterization, toxin profile and response to light intensity”, this article includes contributions from two MaHeWa researchers: Thierry Jauffrais and Manoella Sibat.
The study focuses on Gambierdiscus polynesiensis, a dinoflagellate known for producing neurotoxins involved in ciguatera fish poisoning. In New Caledonia, where knowledge gaps persist regarding the phenomenon and the microalgae responsible, the authors describe a newly identified strain of G. polynesiensis — the first recorded outside the Polynesian archipelago. They also provide its toxin profile and its response to different light intensities.
This work directly supports the objectives of WP2, coordinated by G. Mitta (Ifremer, French Polynesia), which seeks to understand the effects of marine heatwaves on coral ecosystems and biosafety, particularly through the lens of ciguatera. The results offer critical insights into the environmental conditions that enhance the toxicity of these microalgae, contributing valuable elements for anticipating and managing public health risks.
This discovery marks an important step for New Caledonia, where ciguatera represents a major health challenge. By clarifying the behaviour and toxin production of G. polynesiensis, this study strengthens the scientific foundation needed for improved prevention and protection of both communities and marine ecosystems.
The article is available online:
— Publisher’s version: https://doi.org/10.1016/j.hal.2025.102859
— Open Access version: https://archimer.ifremer.fr/doc/00948/105952/
This research was also presented at the International Symposium on Ciguatera Poisoning in the Pacific Islands, held from 19 to 22 May 2025 in Nelson, New Zealand.
©2024 MaHeWa
