Restoring Coral Reefs: Lessons from Puerto Rico and St. Vincent and the Grenadines

In the Caribbean, organizations like ISER Caribe and Richmond Vale Academy (RVA), in Puerto Rico and St. Vincent and the Grenadines, respectively, are leading the way in innovating coral reef restoration, implementing novel pioneering strategies that could make a difference in the survival of these crucial ecosystems.

Coral reefs are more than just underwater landscapes of breathtaking beauty; they serve as vital barriers protecting coastlines and are a source of invaluable biodiversity. However, current threats—from the climate crisis to lethal diseases—have devastated these ecosystems.

Restoring corals in an era of climate crisis is essential. These efforts not only aid coral populations in recovering and adapting to change, but also prevent the extinction of species, enhance reef connectivity, and facilitate migration to new areas.

From a social standpoint, these initiatives offer educational, tourism, and economic opportunities for local communities and create management roles through training programs for diverse and community awareness campaigns.

Sea and Land-Based Nurseries

ISER Caribe's Center for Research and Restoration of Marine Organisms (CIROM), in Puerto Rico, emphasizes a holistic view by focusing on the entire ecosystem, rather than solely on the corals. They integrate marine species—such as sea urchins and crabs—which maintain balance within the reef ecosystem by controlling algae growth. This balance is essential for coral survival, since algae not only blocks the coral from necessary sunlight, but can ultimately smother them.

The center’s efforts in restoring sea urchin populations—which faced a 98% decline in the late 1980s—are vital in this holistic restoration method. Last year, CIROM’s initiative at La Parguera—a town on the southwest coast of Puerto Rico— planted over 10,000 coral fragments, and initiated a sea urchin breeding program to boost ecosystem health.

Corals have two ways of reproducing: sexual and asexual. The asexual method is done in the nursery, on land; it's a pioneer approach of CIROM that allows the coral to propagate. This method reproduces the natural process in which a coral splits, and forms another colony that is genetically equal to the mother colony.

At their land-based nurseries in La Parguera and Ceiba—on the eastside of Puerto Rico—CIROM’s team uses this microfragmentation on corals that have been impacted by stranding, that survived disease, or are in danger of extinction, to accelerate coral growth and resilience.

“We focus on massive corals, fragment them, and place them on cement plates to form larger colonies in much less time," explained Jorge Casillas, CIROM’s operations manager.

These nurseries control temperature, providing a safe environment for corals to grow free from the stress of ocean bleaching events.

In St. Vincent and the Grenadines, the Richmond Vale Academy collaborates with CLEAR Caribbean Ltd., a non-profit company focused on tackling environmental degradation and human vulnerability to the climate crisis.

The Academy and CLEAR Caribbean collaborate to establish sea-based nurseries. Together, their work has focused on reviving elkhorn and staghorn corals, nearly wiped out by white band disease in the 1980s. Project Leader Tobias Herberg shared that despite the challenges—such as volcanic eruptions and hurricanes—RVA’s coral propagation had seen an 85% survival rate before the bleaching that started in September, 2024, with 18,000 fragments replanted. Due to the scattered nature of the different outplant areas in the Grenadines, it is difficult to estimate the exact area being restored. On St. Vincent, however, the restored area is estimated in 74 acres.

Nevertheless, there is no permanent victory in this environmental fight: this recent bleaching—which lasted until this February—caused about 90% mortality in both nursery fragments and natural source colonies. Herberg said that they are currently focusing on doing weekly surveys to try to locate survivors, and exploring the possibility of creating a land nursery where conditions can be easier controlled.

Coastal Communities Involvement

CIROM’s work is supported  by educational outreach, including internship programs and volunteer initiatives. These efforts pretend that future generations engage in marine conservation. The center’s initiatives in Ceiba have similarly made strides, doubling its solar energy capacity and expanding its nursery facilities to ensure coral species’ survival during extreme climate events.

RVA has also embraced a holistic view of coral restoration, incorporating local communities into the process. Their certified divers, boat captains and volunteers play a pivotal role in the success of the nurseries and coral outplanting programs across St. Vincent and the Grenadines. In total, 16 residents of coastal communities on mainland St. Vincent have been employed part time as divers due to their highly recognized PADI certifications.

A Piece of the Restoration Puzzle

Despite their success, Jorge Casillas from ISER Caribe cautions that this technique is only one part of a broader solution. In other nurseries, such as in La Parguera they are experimenting with the sexual reproduction of corals, adding an additional layer of genetic diversity to the process.

“This is not the complete solution, but it is one piece of the puzzle," he explained.

ISER Caribe is expanding the CIROM facility in Ceiba and improving its laboratory capabilities to accelerate reef recovery. In this lab, scientists at CIROM refine techniques that enhance coral resilience.

Meanwhile, the efforts in St. Vincent and the Grenadines are likewise a drop in the ocean, according to project lead Herberg, as there are many miles of corals left to be surveyed and replenished. According to the researcher, this process will undoubtedly take many years and demand great financial resources. Herberg said that there is no fixed estimate as to what is needed for the project as it continues to be executed in phases as funds come in.

Despite the challenges looming ahead, the RVA and supporting agencies continue to provide the help needed in critical areas to ensure greater sustainability. However, the long-term will depend heavily on the level of financial support available. The RVA is currently getting funding from the Caribbean Biodiversity Fund, and has applied for some other grants that have yet to be approved. Meanwhile, their staff started a marine conservation program in which people can pay a fee to join. The money raised through this program allows the RVA to do the work even if outside funding stops.

Regional Caribbean: Partnerships for Restoration

ISER Caribe’s work does not exist in a vacuum: it is part of a broader movement across the Caribbean, where multiple organizations and governmental agencies are beginning collaborations to address the reef crisis. The MAR Foundation in the Dominican Republic, for example, has developed similar coral restoration programs, focusing on Acropora cervicornis, a branching species that provides key habitats for marine life.

In Jamaica, the Coral Conservation Alliance has worked on reef restoration by planting coral fragments on artificial structures, a technique that has shown promising results.

In St. Vincent and the Grenadines, the RVA is looking into different opportunities to share fragments amongst Caribbean islands, in tandem with the government, according to Herberg. They are sorting coral fragments from nearby islands where corals are more resilient and have weathered the storm despite the warmer temperatures.

Climate justice entails addressing the disproportionate impact of climate change on vulnerable communities. The restoration of coral reefs directly aligns with these principles, as healthy reefs can provide critical resources and protection for coastal communities. ​​After all, 25% of all marine life depends on coral reefs, and they act as natural barriers that protect coastlines from waves, storms and erosion.

Restoring coral reefs is a race against time, one that requires constant innovation and regional collaboration. The combined efforts of ISER Caribe, RVA, and other Caribbean organizations show that coral reefs can be saved, but only if resources, support, and collective action are sustained.

This story was published with the support of the Caribbean Climate Justice Journalism Fellowship, which is a joint venture of Climate Tracker and Open Society Foundations.

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Laura M. Quintero and Luis Alfaro edited this story.