Abstract
Coral reefs provide essential ecosystem services and livelihoods, particularly for small island nations like the Maldives. However, they are increasingly threatened by climate change and coastal modification. In 2022, the Greater Malé Connectivity Project (GMCP) commenced in North Malé Atoll, involving large-scale land reclamation and marine construction that affected adjacent coral reefs. As a mitigation measure, coral colonies were relocated to the reef surrounding Villimalé Island. Over two years of monitoring, relocated corals showed encouraging performance despite challenging environmental conditions. Overall survival reached 66%, with larger colonies outperforming smaller fragments and Pocillopora generally exhibiting higher growth and thermal resistance than Acropora. Growth rates declined with rising sea surface temperature, and mortality was primarily associated with tissue-loss responses rather than predation or ectosymbiotic colonisation. Health trajectories differed among coral types: Acropora fragments were more prone to bleaching, whereas Pocillopora colonies maintained tissue integrity but experienced chronic degradation. Despite these biological interactions and health challenges, many corals acclimatised to the urban reef environment, underscoring that coral relocation, when combined with species selection and size consideration, can serve as a viable short-term conservation tool in highly impacted systems.
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Data availability
Data are available on request to the corresponding author due to restrictions and ownership of the NGO Save the Beach Maldives.
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Acknowledgements
The authors wish to thank the Maldivian NGO Save the Beach Maldives for its invaluable support throughout this research, which enabled the continuity of the study over two years. We are especially grateful to all participants involved in the field activities, whose efforts in coral relocation, site maintenance, and voluntary data collection were fundamental to the success of this project. We also extend our sincere thanks to Afcons Infrastructure Limited for permitting the coral relocation prior to the commencement of their operations and for their interest and support in our work.
Funding
Coral relocation activities were funded by Afcons Infrastructure Limited. The restoration project was partially supported by the GHOST NETS project (Ministry of Environment and Energy Security, PNRR Mission 2, ISPRA, Italy).
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Conceptualization, I.P. and D.T.; methodology, I.P. and H.A.; software, M.M. and I.P.; validation, M.M., I.P. and H.A.; formal analysis, I.P., D.T., V.A.; investigation, I.P., H.A; resources, H.A., I.P. and M.M.; data curation, I.P., D.T. and V.A.; writing—original draft preparation, I.P. and D.T.; writing—review and editing, M.M., I.P. and V.A.; visualization, I.P. and D.T.; supervision, M.M. and I.P.; project administration, I.P. and H.A.; funding acquisition, H.A. and M.M. All authors have read and agreed to the published version of the manuscript.
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Pancrazi, I., Tritini, D., Ahmed, H. et al. Coral relocation supports survival and growth in an urban reef of the Maldives.
Sci Rep (2025). https://doi.org/10.1038/s41598-025-33671-7
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DOI: https://doi.org/10.1038/s41598-025-33671-7
Keywords
- Coral relocation and restoration
- Biodiversity conservation
- Restoration performance
- Anthropogenic pressure
- Maldives
Source: Ecology - nature.com
