Coral reefs provide habitat to many organisms, while protecting shorelines and contributing to sustainability of livelihoods. Unfortunately, these valuable ecosystems are exposed to multiple stressors that are significantly reducing coral populations faster than they can reproduce and recover. In the largest archipelago of the Caribbean basin, The Bahamas, the majority of coral loss has been attributed to mass bleaching events and consecutive disease outbreaks, owing their low abundance, their capacity to produce viable offspring during spawning events have been compromised. To help counteract coral reef decline, a collaboration between the Perry Institute for Marine Science, the Cape Eleuthera Institute, and The Nature Conservancy, was established as The Bahamas Coral Innovation Hub, using mariculture as a tool to increase abundance and improve genetic diversity.
After mass mortalities of Acroporids in the Caribbean, coral gardening (increase abundance of coral populations) has been proven to be an effective method for use in coral restoration efforts. At the hub, corals have been propagated using ocean-based nurseries (Figure 1), using mid-water floating coral nurseries, while identifying resilient and fast-growing genets.
In order to increase genetic diversity, larval propagation has been implemented. Most Caribbean coral species, release gametes into the water column during synchronized
spawning events, the Hub has been developing predictions since 2020. During coral spawning, gametes can be collected and reared in lab and ocean-based facilities (Figure 2), where fertilization has higher rates than would occur naturally. The resulting coral offspring can then be returned to the reef where they will continue to grow and increase coral cover on degraded reefs.
Understanding and studying early life stages, while identifying resilient corals could enhance survival of corals exposed to changing conditions and environmental stressors. Healthy coral reefs are needed in many small island developing nations like The Bahamas, where tourism is the number one source of income for the country and many residents make their livelihoods through commercial fishing. With genetic diversity comes resistance and resilience to many common stressors such as ocean temperatures rising and coral diseases.