Scientific Cruise 2024 REPORT

Between May 5 and May 19, 2024, the 27th Scientific Cruise took place in the Maldives, covering the central atolls of the Archipelago: Ari, North Malé, South Malé, and Felidhoo, for a total of 24 monitored sites, including lagoonal and oceanic reefs.

Thanks to the contribution of over 30 participants, including researchers, professors, and students from the Universities of Genoa and Bari, it was possible to collect data on long-term historical series (coral community structure, coral recruitment, reef geomorphology, and application of the international ‘Reef Check’ protocol). Additionally, new monitoring efforts were included. The collaboration with the University of Bari allowed for in-depth studies on gorgonians and black corals, as well as a preliminary survey on the ascidian population. Professors and researchers from the University of Genoa began a study to characterize marine sponges, echinoderms, and insects found on islands and at the water's surface. Furthermore, to specifically monitor the ongoing bleaching event, the Maldivian national protocol developed by the Maldives Marine Research Institute (MMRI) was applied.

The preliminary results from this latest cruise show encouraging signs confirming the recovery trend in many of the monitored reefs. However, many reefs have been severely impacted due to the thermal anomaly that caused the 4th global bleaching event. Although the bleaching primarily affected shallow depths (3-7m), it strongly impacted the more sensitive genera, particularly Acropora, which was almost always observed bleached or with fluorescent colouration (a sign of severe stress). This latest bleaching event appears to have been less severe than the one in 2016; however, only after the thermal anomaly subsides will it be possible to assess the mortality caused by this new event.

Climate change projections suggest that these anomalous climatic events will inevitably become more frequent in the coming years, posing a significant challenge to the resilience of coral reefs. In this context, continued research and monitoring activities during upcoming scientific cruises will be essential to verify the adaptation and survival strategies of coral communities and predict the future of Maldivian reefs. Moreover, the new studies initiated during the 2024 Scientific Cruise will continue in the coming years, deepening our understanding of the communities inhabiting Maldivian coral reefs.