Flourishing Communities of Coral Reef Offer a Glimpse of Hope

Despite the declining health of coral reefs worldwide, scientists have found hope in a number flourishing coral communities in the Pacific and western Atlantic. A global organization of academics has teamed up to study the reason that pockets of coral reef have prospered against the odds while so many others struggle for survival.

Researchers from 12 institutions across three countries studied four primary locations in the Pacific and Caribbean, observing data on how coral have escaped, resisted, or revived from changes in their environment. The team published their findings in the Journal of Applied Ecology with the hopes of spreading knowledge of how to preserve one of the world’s most threatened ecosystems.

The project involved using long-term monitoring of coral sites in the Pacific (the main Hawaiian Islands and Moorea, French Polynesia) and western Atlantic (the Florida Keys and St. John, US Virgin Islands). Among the 123 sites analyzed, 38 deviated positively and were categorized as “oases.”

The publication describes “escape oases” as those communities of coral that have endured destructive factors such as bleaching, attacks from coral-eating sea stars, or hurricane damage. “Resist oases” refer to thriving pockets of coral that have flourished despite environmental challenges. Meanwhile, “rebounded oases” have suffered similar destructive forces as other negatively affected coral, but have managed to “rebound” to vital conditions.

Researchers have attributed a number of factors as to why certain coral respond better to changes in the environment. In some cases, the location allows for a higher likelihood of survival. For example, coral in deeper waters can withstand storms better than in shallow areas. In other circumstances, the coral may possess more resilient characteristics that allow them to endure and rebound faster from environmental changes.

Lead investigator, Peter Edmunds of California State University Northridge, said he felt especially “blown away” by the recovery of the Moorea reefs of French Polynesia in the Pacific.

He shared, “We started working there in 2005 and almost immediately encountered hordes of coral-eating sea stars that quickly consumed the tissue of the corals. By 2010, there was as close to zero coral on the outer reefs as I have seen in my entire career. And yet, within eight years, that coral has regrown. In places, about 80 percent of the sea floor is now covered by live coral. It is a remarkable example of an oasis.”

Evaluating how certain regions have managed to thrive, despite changes in their environment, suggests new approaches of conservation and restoration in dying coral populations.

Dr. James Guest of Newcastle University, one of the lead authors of the paper, elaborated,” This glimmer of hope does not mean we can be complacent about the severity of the crisis facing most of the world’s coral reefs. But it does give us a starting point from which to understand why some ecosystems might be more resistant than others and to identify areas that warrant stronger protection or specific management strategies, such as restoration or mitigation.”

Although the decline of the world’s coral reef population remains severe, scientists can use information from these thriving communities to enhance coral conservation efforts worldwide.