Great Barrier Reef Coral Frozen in World-First Trial
Story and Photos by Reuters
Scientists researching Australia’s Great Barrier Reef have successfully tested a new method for freezing and storing coral larvae that could help restore reefs damaged by climate change.
Researchers are scrambling to protect coral reefs as rising ocean temperatures destabilize delicate ecosystems. The Great Barrier Reef, which encompasses 3,000 individual reefs and is the biggest living structure on Earth, has sustained four bleaching events in the past seven years, including the first bleach during a La Nina phenomenon, which typically brings cooler temperatures. When water is too warm, corals expel the algae living in their tissues, turning the coral white.
Bleaching threatens marine species that depend on coral reefs for survival and can affect human livelihoods and food security. Cryogenically frozen coral can be stored and reintroduced to the wild, but the current process requires sophisticated equipment including lasers. Scientists say a new lightweight “cryomesh” can be manufactured cheaply and better preserves coral.
In a December 2022 lab trial, the world’s first with Great Barrier Reef coral, scientists used the cryomesh to freeze coral larvae at the Australian Institute of Marine Science (AIMS). The coral was collected from the reef for the trial, which coincided with the brief annual spawning window.
“If we can secure the biodiversity of coral … then we’ll have tools for the future to really help restore the reefs, and this technology for coral reefs in the future is a real game-changer,” Mary Hagedorn, a senior research scientist at the United States-based Smithsonian National Zoo and Conservation Biology Institute, said while working at the AIMS lab.
The cryomesh was previously used on smaller and larger varieties of Hawaiian corals, although the trial on the larger variety failed.
Trials with larger varieties of Great Barrier Reef coral involve scientists from AIMS, the Smithsonian, the Great Barrier Reef Foundation and the Taronga Conservation Society Australia as part of the Reef Restoration and Adaptation Program.
The mesh technology, which will help store coral larvae at minus 196 Celsius (minus 320.8 Fahrenheit), was devised by a team from the University of Minnesota’s College of Science and Engineering. It will allow for the freezing and storing of larvae “at a scale that can actually help to support some of the aquaculture and restoration interventions,” said Jonathan Daly of the Taronga Conservation Society Australia.
