Email Print Share
January 15, 2021

Study offers hope for coral reefs battling intense heat waves

An international research team discovered that some corals managed to survive a globally unprecedented heatwave during the 2015-2016 El Niño. Heat stress from that El Niño triggered the third-ever global coral bleaching event, causing mass coral bleaching and mortality on reefs around the world. Until this study, coral recovery from bleaching has only ever been observed after heat stress subsides.

Credit: National Science Foundation/Karson Productions

Coral comeback.

I'm Bob Karson with the Discovery Files, from NSF -- the U.S. National Science Foundation.

(Sound effect: undersea sounds) Corals. Colorful living underwater wonders that help keep the marine ecosystem thriving. During major heatwaves though, are prone to a devastating condition called 'coral bleaching'.

Coral are extremely sensitive to temperature. Water temps can rise to the point that stress the coral into releasing the algae that live in their tissues -- algae that produce food for them. The coral turn an anemic white -- barely alive. Within weeks, without food they will starve and die.

(Sound effect: rough surf) Christmas Island, a coral atoll in the Pacific Ocean. Led by the University of Hawai'i at Mānoa, an international team of researchers headed to this epicenter of one of the most intense coral bleachings ever a 10-month El Niño-driven heatwave in 2015 and '16 that caused the third known global coral bleaching event.

The NSF-supported team found that despite these extreme conditions; some coral survived. As long as they weren't subjected to other types of triggers like water pollution. The team is studying how and why certain corals lived through it in hopes of developing ways for future coral colonies to make a comeback after facing higher temperatures. As the UN's Decade of Ocean Science for Sustainable Development kicks off, they're jumping in with both feet (Sound effect: splash!).

So, would you call this team a 'coral group'?

"The discovery files" covers projects funded by the government's National Science Foundation. Federally sponsored research -- brought to you, by you! Learn more at or on our podcast.

Images and other media in the National Science Foundation Multimedia Gallery are available for use in print and electronic material by NSF employees, members of the media, university staff, teachers and the general public. All media in the gallery are intended for personal, educational and nonprofit/non-commercial use only.

Images credited to the National Science Foundation, a federal agency, are in the public domain. The images were created by employees of the United States Government as part of their official duties or prepared by contractors as "works for hire" for NSF. You may freely use NSF-credited images and, at your discretion, credit NSF with a "Courtesy: National Science Foundation" notation.

Additional information about general usage can be found in Conditions.