A team of Stanford University researchers led by Professor Stephen Palumbi joined the Palau International Coral Reef Center (PICRC) last month to complete the final phase of a three-year research project mapping heat tolerant corals in Palau. The collaborative study will indicate how Palau’s reefs may respond to climate change, and can be used to guide new coral reef management initiatives.
Researcher Victor Nestor led PICRC’s involvement in the project, and has worked alongside Professor Palumbi’s team since the project began in 2018. Together, they have tested hundreds of coral from 39 reefs throughout Palau, which they exposed to high water temperatures in PICRC’s lab, simulating ocean warming.
The coral samples that survived the high temperature treatments demonstrated heat tolerance, signaling that they are better adapted to live in warmer oceans.
“Climate change is a serious threat to corals, and it’s already contributing to reef die-off around the world” said Nestor. “But not all corals respond to heat stress the same way. The heat tolerant corals we have identified are more likely to survive as the ocean heats up, and could lay the foundation for healthy reefs in the future.”
The research team found that heat tolerant corals were both common and widely distributed among the 39 reef sites surveyed. But there were some reefs with higher concentration – the beautiful, coral rich patch reefs in Aimeliik were found to have the most heat tolerant corals. In contrast, some northern reefs were more heat sensitive.
“The fabulous labs, the amazing staff and talented researchers at PICRC make it one of the best places in the Pacific to conduct coral research,” Palumbi said. “And Palau’s dedication to a healthy future ocean means we can work with the conservation directors to help protect the corals most likely to survive warming oceans.”
“As ocean temperatures rise even further, this information will be invaluable for management efforts” agreed Nestor. “Reefs with many heat tolerant corals could be a focus for marine protected areas. Alternatively, heat tolerant corals grown in nurseries could replenish reefs that are struggling.”
The Palumbi Group’s recent visit marked the most recent of several trips to PICRC to conduct field work and administer heat stress experiments. In the coming months, the research team will continue analyzing their heat tolerance data, draw conclusions and develop new coral reef management recommendations for states and communities in Palau.