Cultivating super corals alone is unlikely to protect coral reefs from climate change

by the Coral Reef Alliance
May 11, 2022

OAKLAND, CA – May 11, 2022 – A new study this week shows that a popular coral restoration technique is unlikely to protect coral reefs from climate change, and is based on the assumption that local threats to reefs are managed effectively. The research, published in the journal Ecological Applications, used innovative models to explore the response of coral reefs to restoration projects that propagate corals and outplant them into the wild. Additionally, the study evaluated the effects of outplanting corals genetically adapted to warmer temperatures, sometimes called ‘super corals,’ to reefs experiencing climate change as a way to build resilience to warming.

The models found that neither approach was successful at preventing a decline in coral coverage in the next several hundred years due to climate change, and that selectively breeding corals to be more heat tolerant will only lead to benefits if conducted at a very large scale over the course of centuries. Even then, benefits won’t be realized for 200 years. Restoring areas with corals that haven’t been selected to be more heat tolerant was ineffective at helping corals survive climate change except at the largest supplementation levels explored.

“The scenarios where coral reefs showed the greatest resilience to climate change were those where natural genetic variance was highest, and outplanting heat-tolerant corals in those areas had little to no effect on outcomes,” says Dr. Lukas DeFilippo, who co-led this research as a graduate student and postdoctoral scholar at the University of Washington, and is now a research scientist at the National Oceanic and Atmospheric Administration. 

Keep reading: https://coral.org/en/blog/restoration-2/

Read the Ecological Applications paper: https://esajournals.onlinelibrary.wiley.com/doi/epdf/10.1002/eap.2650