The recent data from the HOPE buoy, deployed in New Caledonia, are enriching MaHeWa’s analyses on the effects of marine heatwaves (MHWs) by revealing very high-frequency dynamics of surface planktonic biomass — capable of quadrupling within hours — which in turn accelerates the formation of carbon-rich “marine snow” that sinks toward the deep ocean.
Illustration: Awareness seminar for healthcare staff.
Our colleague Cyril Dutheil worked with the middle school class (3ème B) of Collège Olympe de Gouges in Cadaujac to make a complex scientific study about marine heatwaves more accessible. This science outreach work was published in the journal DECODER, which is dedicated to making research available to everyone.
The first annual meeting of the MaHeWa project was held from September 26 to 29, 2025, at the Ifremer station in Vairao (Tahiti, French Polynesia).
Since July, Célia Caillibot has joined us at the Ifremer representation office in New Caledonia. Under the supervision of Thierry Jauffrais (IFREMER), Nicolas Lebouvier (UNC), and Philipp Hess (IFREMER), she will be working as part of Work Package 2: Ecological Vulnerability and Biological Impacts.
We are pleased to share our latest article published in Harmful Algae:
“Gambierdiscus polynesiensis from New Caledonia (South West Pacific Ocean): Morpho-molecular characterization, toxin profile and response to light intensity”
This work, contributed to by Thierry Jauffrais and Manoella Sibat, two researchers within the MaHeWa project for WP2 (Biological Impacts and Ecological Vulnerability), focuses on Gambierdiscus polynesiensis. This dinoflagellate is known for producing neurotoxins associated with ciguatera. In New Caledonia, located in the southwest Pacific Ocean, there is currently a significant knowledge gap regarding ciguatera and the microalgae linked to this foodborne illness. This study describes a new strain of Gambierdiscus polynesiensis outside the Polynesian archipelago—a first—along with its toxin diversity and response to varying light intensities.
