As part of the CCTs of the MaHeWa project—whose objective is to co-construct crisis-response strategies and long-term adaptation solutions through transdisciplinary approaches—a second workshop was held on 21 October 2025 at the Ifremer center in Vairao. The meeting brought together around thirty participants, including municipal representatives, environmental associations, staff from the Marine Resources Department, representatives of the Interministerial Delegation for Climate and Sustainable Development, and several researchers involved in the project. The workshop aimed to discuss in concrete terms the effects of ocean heatwaves and the collective actions that could be developed to mitigate their impacts on ecosystems and human activities. A first workshop of this kind had already taken place in Nouméa, New Caledonia.
This workshop represented an important step in the participatory construction of the MaHeWa action plan. The objective was not only to present scientific findings but also to confront them with field realities, listen to feedback from local stakeholders, and jointly build intervention scenarios. Through this exchange, the CCTs seek to understand how marine heatwaves are perceived at local scales and to identify solutions that are realistic, operational, and adapted to territorial contexts.
This work is embedded in a long-term strategy: building a network of actors able to monitor alerts, interpret indicators developed by scientific teams, and coordinate responses in real time. Participants also initiated reflection on creating a dedicated management unit capable of responding during marine heatwave events by identifying key contacts and defining procedures to activate.
French Polynesia has experienced many marine heatwave events since the 1980s, with visible consequences such as coral bleaching and mortality of certain species, including giant clams. While ecosystems show strong resilience, projections indicate that these events will intensify in the coming years, with potential impacts on biodiversity, fisheries, pearl farming, and tourism. These challenges reinforce the need for the collective mobilisation fostered by the CCTs.
Similar workshops will continue to be organised through 2029 in French Polynesia, New Caledonia, and Wallis-and-Futuna. They will help refine proposals, test decision-support tools, and strengthen coordination among stakeholders. Ultimately, these efforts aim to generate concrete adaptation measures and inform regional public policies on managing risks associated with marine heatwaves.
Photo credits: Ifremer in the Pacific.
