When a potentially record heatwave hit Florida in July, thousands of corals were rescued and moved to land-based facilities to avoid bleaching. Now that temperatures have dropped to normal levels, healthy corals are ready to return to offshore nurseries.
Bleaching can be fatal to corals. When the water temperature fluctuates dramatically, corals expel algae from their tissues, turning them completely white.
“Protecting our coral reefs is a community effort,” Fanor Montoya Maya, Coral Reef Restoration Program Manager at the Coral Reef Restoration Foundation, said in a press release. “And this has never been more evident than this summer, when our network came together amidst one of the most extreme environmental challenges many of us have ever faced.”
The Keys Marine Laboratory (KML), operated by the Florida Institute of Oceanography (FIO) in Long Key, protected more than 5,000 corals for about four months.
This urgency was reinforced in July when coral restoration experts, including representatives from the Florida Keys National Marine Sanctuary and the Florida Fish and Wildlife Conservation Commission, appealed for help to protect corals from bleaching due to an unprecedented heat wave. occured.
The restoration team began the month-long program on October 30th and successfully reintroduced approximately 360 corals to Tavernier’s offshore nursery on the first day. The plan is to return all rescued corals to nurseries by December.
The restoration process involves a variety of partners, including the Florida Aquarium, Florida Keys National Marine Sanctuary, Florida Fish and Wildlife Conservation Commission, and Coral Restoration Foundation.
KML biologist Nicole Charnock said all corals returned to the ocean must undergo a health check by a coral veterinarian. But he is currently the only veterinarian working on the certification process.
“It’s a pretty rigorous process,” Charnock said. “They’re a little bit limited in terms of how quickly they can get things out. They’re making sure all the corals are healthy and ready for that movement.”
While many healthy corals are waiting to be relocated, researchers are making good use of their time by actively pursuing research.
They employ a technique called microfragmentation, in which a special saw breaks up healthy coral into tiny pieces of one to five polyps. This process stimulates the growth of coral tissue, allowing it to grow into clones at an accelerated rate of 25 to 50 times its normal rate.
“The idea behind it is similar to when you cut your hand and the skin tries to rapidly regrow over the wound,” Charnock says.
Coral reefs are also called the “rainforests of the sea.” They maintain marine habitat, buffer the impact of storms on coastal areas, and support local economies.
Since April 2023, the National Oceanic and Atmospheric Administration (NOAA) has been monitoring a steady rise in ocean temperatures. Record-warm ocean temperatures have caused corals within 3,800 square miles of the Florida Keys National Marine Sanctuary to bleach and die.
In July, sensors in Manatee Bay near Everglades National Park recorded a temperature of 101.1 degrees Fahrenheit, a potential world record.
Bleaching issues are not new to Florida, said Joshua Patterson, associate professor of restorative aquaculture in the University of Florida’s College of Forestry, Fisheries and Geological Sciences. But this summer’s heat has been particularly rapid and more extreme than recorded.
“As far as I can remember, this is the first summer we’ve had an active rescue operation,” he said. “In the past, it was more of a surveillance-type response, just documenting things and doing research to look for things that could survive in heat-tolerant colonies.”
KML, one of the largest temperature-controlled saltwater systems in the Florida Keys, has taken steps to address the bleaching crisis. We tripled the number of pumps to 120 and installed 60 water tanks ranging from 40 gallons to 1,000 gallons.
But extreme weather patterns pose an immediate threat to corals in the Florida Keys next year. Patterson said moving coral back and forth to the ocean may not be a viable solution next summer.
Removing corals from the ocean and bringing them into land-based systems comes with risks. Corals that do not respond well to transport may die. There are also biosecurity concerns that undesirable elements may be inadvertently introduced or released.
In Florida, experts follow strict testing guidelines to ensure corals are tested before they are released back into the ocean.
Patterson said “quite a few” organizations are working on preserving genetic representatives. Columnar corals are a species that occurs naturally in Florida in small numbers, and many are protected in terrestrial systems.
The Florida Aquarium is also focusing on coral spawning in terrestrial systems in hopes of increasing genetic diversity and identifying heat-tolerant corals.
“By learning more about these corals, we may be able to identify corals that are more heat-resistant and disease-resistant,” he says. “However, there is still much to be resolved.”