Florida researchers plan to grow more than 5,000 baby corals in the next couple of years as part of a state effort to recover 25% of a population lost to an epidemic.
Many wild species of Florida coral have been decimated by stony coral tissue loss disease since it was first reported off the coast of Miami-Dade County in 2014.
The outbreak has since spread throughout Florida and to reefs in the Caribbean.
"If we don't have living coral, the reefs eventually collapse, and we no longer have habitat for very important commercial fish species, as well as supporting our tourism and recreation and our coastlines, protecting them from wave energy,” said Keri O’Neil, director of the coral conservation program at The Florida Aquarium’s conservation campus in Apollo Beach.
There’s still not a lot understood about the disease, she said. For instance, what the pathogen even is.
“Although we know that antibiotic treatment with amoxicillin does stop the disease in the field, we can't go around and put antibiotics on millions of corals. That's just not realistic and probably not very good for the environment either,” O’Neil said.
So, the aquarium is using a $2.1 million grant from the Florida Department of Environmental Protection’s Coral Reef Restoration and Recovery Initiative, known as FCR3, to produce and plant a few types of brain coral: grooved, boulder, and symmetrical.
“We are also looking at: do we breed corals that survived the disease or corals that were rescued prior to the disease? If we have offspring that are bred from survivor parents, are they stronger in the long run,” she said.
She added that all these types of decisions are incorporated throughout this process as they learn which juveniles do best.
Along with growing juvenile corals, the aquarium is also producing hundreds of thousands of coral larvae for its scientific partners.
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Coral researchers are keeping heat resilience at the forefront of their breeding process, as well, because O’Neil said climate change is the No. 1 threat to the marine invertebrates right now.
Florida’s water temperatures reached up to 93 degrees in 2023, leading to the state’s most severe coral bleaching event ever recorded.
"The most important thing that we need to consider as we're growing corals is, how can we make them more heat-tolerant and resistant to climate change," she said. “Even maybe raising them at higher temperatures to make them a little bit stronger or more resilient.”
O’Neil said the aquarium has spawned 14 different species of corals native to Florida.
Scientists do this by mimicking all of the natural cues the corals would get in the wild to induce them to mature their eggs and sperm, and then release them in a synchronized spawning event.
You can see an example of a spawning event in the video below:
“We use artificial light cycles that mimic sunrise, sunset and also the lunar phase, as well as seasonal temperature cues, so that the corals that live here full time, the parents, will spawn on their normal annual cycle,” she said.
Each spawning event can produce hundreds of thousands of little juvenile coral larvae.
“And then the real hard work begins, where you actually have to settle those and raise those tiny corals up to be big enough to be returned to the reef with a good survival rate,” O’Neil said.
The lab-grown juvenile corals will support restoration efforts in the Florida Keys National Marine Sanctuary and the Kristin Jacobs Coral Aquatic Preserve in southeastern Florida.
They will be planted by the aquarium and its partners, such as I.CARE, University of Miami, Nova Southeastern University, and The Reef Institute.
The Florida Aquarium is also using the state dollars to pilot a coral spawning training program to share their process with other researchers, projected to start in the spring.
"The Florida Aquarium cannot work and save the reef in a vacuum. This is a massive undertaking. We need many, many people working on coral reproduction and growing out baby corals and planting them back out onto the reef,” O’Neil said.
