Researchers at the Rosenstiel School of Marine, Atmospheric and Earth Science have crossbred corals from Florida and Honduras and planted them onto a living reef – a groundbreaking step to rescue Florida’s reef, which has lost more than 99 percent of its elkhorn coral since the 1980s.
Andrew Baker, professor of marine biology and ecology who directs the Coral Reef Futures Lab at the Rosenstiel School, led the effort with his team. The scientists carried out the outplanting just off Miami’s coast, placing 35 hybrid “Flonduran” corals alongside 35 Florida-only corals on reefs near Key Biscayne.
“This project is the first step to see if we can help evolution along,” said Juli Berwald, science writer and co-founder of the nonprofit Tela Coral. “If we succeed here, it puts down a flagstone on the path to doing it in other places.”
Elkhorn coral, once the backbone of Florida’s reefs, has declined by more than 99 percent since the 1980s. Rising ocean temperatures, pollution and disease have left so few colonies that they can no longer reproduce naturally.
Tela Bay, Honduras, offers a rare bright spot. Despite warm, murky water and decades of runoff from banana plantations, its reefs remain healthy. Baker called Tela’s corals “unusually resilient,” noting that they thrive in the same stressful conditions now threatening Florida’s reefs.
In June 2024, Rosenstiel scientists and partners at Tela Marine collected fragments and DNA samples from corals in Honduras. A month later, corals from both Honduras and Florida spawned successfully at Rosenstiel and The Florida Aquarium in Apollo Beach, producing more than 200 hybrid babies.
The work was made possible by permits from the Honduran government to export the corals, from Florida’s Fish and Wildlife Conservation Commission to outplant them on Miami’s reef. National Oceanic and Atmospheric Administration Coral Reef Conservation Program funded the initiative.
So far, none of the young corals have died, even as water temperature rose over the summer. Baker’s team is watching closely to see how they respond to bleaching stress in the coming months.
Berwald suggested that Tela’s unusual resilience may track back to the early 1900s, when banana plantations first brought fertilizer runoff into the bay decades before most of the Caribbean.
“Maybe they have had more time to adapt to hotter, more polluted conditions,” she said.
The long-term goal is for hybrids to survive, grow to maturity, and eventually spawn on their own, rebuilding the dense elkhorn thickets that once sheltered reef life.
“Success would look like thickets of elkhorn and staghorn again on tops of reefs, bringing back the homes for fish, snails, lobsters, crabs, everything that lived there,” Berwald said.
Florida’s reef is one of the state’s most iconic ecosystems, and its collapse would ripple through fisheries, tourism, and coastal protection. “Corals are the habitat builders. They are the trees of the rainforest. You lose corals, and you lose the reef,” Baker said.
For Rosenstiel students, the project provides hope that reef restoration is still within reach.
“This feels like a real step in the right direction,” said Micheal Gallant, sophomore marine biology student at Rosenstiel. “It makes me think that our generation really can make a difference, and that there are still solutions worth fighting for.”
Berwald said students should take inspiration from the effort itself.
“This required so many partners to come together, so many approvals, so much grit,” Berwald said. “There will always be stumbling blocks. Keep pushing through them.”
She stressed that the project’s legacy belongs to the entire student body, not just Rosenstiel students.
“Reefs are part of your world in Miami. The fact that they are declining is not normal,” she said. “Paying attention matters because it is your legacy.”