UH Researchers Contribute to Largest-Ever Study of Coral Communities

Abundant schools of reef fishes among coral on an Indonesian reef. Photo courtesy of UH/Erik Franklin, Hawaiʻi Institute of Marine Biology

The largest study of its kind has identified where and how to save coral reef communities in the Indo Pacific, according to an international group of scientists, including University of Hawaiʻi at Mānoa researchers Erik Franklin, Camilo Mora and Kuʻulei Rodgers and others from conservation NGOs, government agencies and universities, as recently reported by UH.

The study outlines three viable strategies that can be quickly enacted to help save coral reefs that are threatened by climate change and human impacts — protect, recover and transform.

The study involved the efforts of more than 80 authors who surveyed coral abundance on more than 2,500 reefs across 44 countries in the Indian and Pacific Oceans. The findings revealed that the majority of reefs had functioning coral communities with a living cover of architecturally complex species that give reefs their distinctive structure. The study was published in Nature Ecology and Evolution.

Local, Global Factors Impact Reef Health

Erik Franklin during recent scientific work in Indonesia. Photo courtesy of UH/Erik Franklin, Hawaiʻi Institute of Marine Biology

“The study provides a roadmap for reef managers to identify areas that can benefit from active management practices at a local scale while also preparing for potential future impacts from increasing climate hazards,” said Franklin, co-author of the study and assistant research professor at the Hawaiʻi Institute of Marine Biology in the UH Mānoa School of Ocean and Earth Science and Technology.

Increasing carbon emissions and human impacts of overfishing, pollution and unsustainable development have led to predictions of a bleak future for tropical reefs and the millions of people who depend on them. After the damage caused by severe heat stress during the 2014-2017 El Niño event, the authors found nearly 450 reefs in 22 countries across the Indo-Pacific that survived in climate “cool spots” that should be prioritized for urgent protection and management.

“The good news is that functioning coral reefs still exist, and our study shows that it is not too late to save them,” said study lead author Emily Darling, a Wildlife Conservation Society conservation scientist and leader of WCS’s global coral reef monitoring program. “Safeguarding coral reefs into the future means protecting the world’s last functioning reefs and recovering reefs impacted by climate change. But realistically — on severely degraded reefs — coastal societies will need to find new livelihoods for the future.”

The study also identifies the minimum requirements to save functioning reefs. This required evaluating the impacts of 20 environmental, climatic and human-caused stressors on reef-building corals. The authors found that higher abundances of framework corals, the species that build the backbone of coral reefs, occurred in locations with fewer climate shocks and longer recovery windows. Higher coral abundances were also found farther from coastal populations and their associated markets and agricultural impacts.

For more on the three strategic choices of management for the reefs, see the SOEST website.