The MSC Foundation has completed a new phase of its marine restoration project in the Bahamas, transplanting 32 fragments of elkhorn coral—an endangered species—that were cultivated in nurseries onto nearby reefs off Browns Cay. With this effort, its Super Coral Reefs program has now replanted more than 285 corals.
In light of forecasts predicting record-high ocean temperatures this summer, the Foundation has also decided to temporarily suspend new transplants. The goal is to protect the remaining fragments in underwater nurseries, where they are sheltered until sea conditions improve.
The elk horn coral (“Acropora palmata”) is a keystone species in the Caribbean, but it is critically endangered; reports indicate a 97% decline in its population throughout the Caribbean since the 1980s and its complete disappearance in many areas following the 2023–24 marine heatwave. For the Bahamas, the moosehorn coral is essential, as it acts as a natural barrier that protects the coastline and provides shelter for fish and invertebrates that are vital to local fisheries and tourism.
“Exceptionally warm ocean conditions are expected this year, which could put the corals under significant stress,” said Emeline Bouchet, director of the Marine Program at the Ocean Cay Marine Conservation Center.“NOAA’s Coral Reef Watch forecasts Level 2 bleaching conditions for the northern Bahamas through September. As a result, we have set aside more fragments in our underwater nurseries, where our team can closely monitor and manage them. Restoration isn’t just about planting more corals—it’s also about placing them in the best possible position to thrive.”
As part of the program, coral fragments are cultivated in underwater nurseries before being “transplanted to natural reefs.” This careful process promotes ecosystem regeneration and allows for the collection of data that will serve as the basis for future restoration efforts.
The Browns Cay site was selected following reef studies and biodiversity assessments that confirmed it met the ideal conditions for the relocation of the species. Weather forecasts indicated an increased risk of marine heat stress in the northern Caribbean toward the end of summer. This rise in temperature disrupts the relationship between corals and the microscopic algae living inside them, which give the corals their characteristic color and provide them with much of their food. When subjected to thermal stress, corals expel the algae and lose their color—a phenomenon known as coral bleaching. Deprived of their primary food source, corals become severely weakened, making them more vulnerable to disease and potentially leading to their death.
The corals collected, cultivated, and transplanted at Ocean Cay come from selected colonies that demonstrated a natural tolerance to thermal stress and a 100% survival rate during the 2023–24 heatwave. Since temperatures during the next marine heatwave are expected to reach even higher levels, marine scientists will conduct monthly monitoring of the coral reefs around Ocean Cay to assess the health and resilience of both the transplanted and native corals. Using photogrammetry techniques, researchers create 3D models that track the growth and health of the colonies over time. The next steps will involve resuming replanting efforts once the marine heatwave has passed and restocking the nursery with new coral fragments to ensure a continuous cycle of growth and restoration.
