Finding heat tolerant corals

As global warming causes temperatures to rise in oceans across the globe, it will be critical to discover novel ways to identify reef corals that are susceptible or tolerant to future heating for those reefs to survive and thrive into the future. Coral reefs provide many benefits for ecosystems - supporting 25% of all marine species and acting as hotbeds for biodiversity - as well as the communities in which they are located. The reefs protect coastlines from erosion and storms, provide jobs for local communities and provide recreation activities for locals and tourists.

Two new studies with an international group of researchers, including those from the University of Delaware, are looking to determine how different coral species respond to water temperature fluctuations by sampling coral species in Fiji, Guam and Florida. The goal is to determine which coral can be used in different environments to help with coral reef restoration projects and to improve the resiliency of reef systems through transplanting corals with high thermal tolerance.

The research is led at UD by Mark Warner, professor in the School of Marine Science and Policy in UD's College of Earth, Ocean and Environment.

The first project is funded through a $615,000 grant from the National Oceanic and Atmospheric Administration's (NOAA) Ruth Gates Innovation Grant and was given to Warner, Kenneth Hoadley, an assistant professor at University of Alabama based at the Dauphin Island Sea Lab and the lead on both projects, and Mote Marine Laboratory. This project will focus on the Florida Keys.

The second project is funded by a $1.5 million award from the Coral Research and Development Accelerator Platform (CORDAP), a large-scale initiative, with funds coming from the G20 and managed through King Abdullah University of Science and Technology in Saudi Arabia. This project involves Warner, Hoadley and their colleagues involved in reef restoration and research in Fiji and Guam - Victor Bonito of Reef Explorer Fiji and Bastian Bentlage and Laurie Raymundo at the University of Guam.

Both projects will begin in 2024 and are funded for three years.

Diverse test sites

Warner said having the projects focused on Fiji and Guam, as well as Florida, will allow researchers to look at two areas of the world where the corals have been damaged because of climate change.

"It's a tricky time in Florida because the reefs have just been battered so badly," said Warner, who pointed out that last summer water temperatures rose so drastically that the Florida Keys were suffering from massive bleaching. "Florida has been hammered by elevated seawater temperatures and hammered by disease. It already has low coral cover and less than 10% of that cover is the reef building corals."