Transplanting communities of invertebrates and microbes from a healthy coral reef to a degraded one dramatically boosts coral health, increasing their resilience and reducing stress. This innovative ecosystem transplant could become a powerful new tool to restore dying reefs and protect these vital underwater ecosystems from collapse.
A groundbreaking study reveals that transferring organismal communities from a healthy coral reef to a degraded one significantly improves coral health and resilience. Corals attached to transplanted tiles from a pristine reef showed enhanced photochemical efficiency, increased symbiotic algae, and reduced stress compared to those on degraded reef substrates.
Coral reefs worldwide face degradation due to environmental stressors, impacting not only corals but also the complex communities of invertebrates and microbes that support reef ecosystems. Understanding how these organismal communities influence coral health is crucial for developing effective reef restoration strategies.
This study was conducted by a team led by Natalie Levy and Oren Levy from Bar-Ilan University and collaborators at James Cook University and other institutions. Their research was published in Nature Communications in November 2024.
The researchers used biomimetic terracotta tiles designed to mimic natural reef surfaces, deploying them for six months at two sites in the Gulf of Eilat/Aqaba, Red Sea: a healthy, non-urbanized reef (Site A) and a degraded, urbanized reef (Site B). After conditioning, the tiles were reciprocally transplanted between sites, and two coral species—Acropora eurystoma and Stylophora pistillata—were attached for an additional six months to assess physiological responses.
After one year, tiles from the healthy reef transplanted to the degraded site hosted significantly richer and more diverse invertebrate communities than the original degraded tiles. Key beneficial bacteria from the healthy reef were more prevalent on these transplanted tiles. Corals from the degraded reef attached to healthy-site tiles exhibited higher photochemical capacity, increased density of endosymbiotic algae, and lower physiological stress markers such as antioxidant capacity, indicating improved coral health and resilience.
These findings suggest that community transplantation—moving reef-associated organisms—could be a promising restoration tool to enhance coral health and combat reef degradation. By boosting the microbial and invertebrate communities that support coral physiology, this approach may help reefs better withstand environmental stressors and improve their chances of recovery.
Future research could include additional species, particularly slower-growing species such as Platygyra. Nonetheless, Acropora is the most used species of coral in restoration efforts, so the findings of the study are particularly valuable for restoration efforts.
Why it matters.
Coral are susceptible to a range of human and environmental stressors. They are also slow growing and often rely on their symbionts, which can themselves be affected by stressors, ultimately making their restoration difficult. Finding ways to enhance restoration success, such as community transplantation, is crucial to ensure the survival and functioning of coral in future oceans.
References:
Study:
Levy, N., Marques, J. A., Simon-Blecher, N., Bourne, D. G., Doniger, T., Benichou, J. I. C., Lim, J. Y., Tarazi, E., & Levy, O. (2024). Ecosystem transplant from a healthy reef boosts coral health at a degraded reef. Nature Communications, 15, 10033. https://doi.org/10.1038/s41467-024-54149-6
Further reading:
Rosado, P. M. et al. (2019). Marine probiotics: increasing coral resistance to bleaching through microbiome manipulation. ISME Journal, 13, 921–936.
Bourne, D. G., Morrow, K. M., & Webster, N. S. (2016). Insights into the coral microbiome: underpinning the health and resilience of reef ecosystems. Annual Review of Microbiology, 70, 317–340.
Hughes, T. P. et al. (2017). Global warming and recurrent mass bleaching of corals. Nature, 543, 373–377.
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