Both the deterioration of the Florida Keys reef and the response to it took time. Staghorn and elkhorn corals grew so numerous throughout the Florida Reef Tract for decades that divers reported swimming through underwater thickets. These corals were dying back because of disease, bleaching and storm damage, and in some places their populations had dropped by almost 90%. It took more than good intentions to mend that kind of loss. The breakthrough grew from a father-daughter 4-H project that built on Nedimyer’s years of experience working with marine life and aquaculture.A family project among the reef fishKen Nedimyer is a tropical fish collector and aquaculture operator based in the Florida Keys. He’s been diving those reefs since he was a kid and has witnessed them change for the worse over the years. Around 2000, when his daughter had a 4-H Youth Development project, Nedimyer used his experience with marine life to help her experiment with coral propagation. Together, they began growing staghorn coral fragments that had broken from nearby reefs. They began propagating staghorn coral fragments, keeping pieces that had broken from nearby reefs alive rather than leaving them to die on the seafloor.The small experiment went well enough that Nedimyer donated the propagated staghorn to the Florida Keys National Marine Sanctuary for restoration use, and a grant from The Nature Conservancy soon followed, allowing him to expand what had started out as a backyard hobby into something closer to a proper coral nursery. That early achievement posed a specific question. If a few saved bits could grow this nicely by chance, how many more could grow on purpose, and how quickly?Building coral tree nurseries that outgrow the ocean floorIn 2007, Nedimyer founded the Coral Restoration Foundation in Key Largo, where his team developed offshore nurseries that suspended coral fragments from structures known as coral trees rather than growing them directly on the seafloor. Branching corals developed in this fashion and grew far faster than those left on the reef. Corals reportedly grew from a finger-sized fragment to a basketball-sized colony in six to nine months. At that point, divers would cut parts free and reattach them to neighbouring deteriorated reef sites.That speed changed the economics of reef coral regrowth. Rather than waiting years for a few colonies to recover by themselves, restoration teams could grow corals in offshore nurseries and then outplant them onto degraded reefs when they were large enough. A PLOS ONE study tracking Coral Restoration Foundation outplanting projects between 2007 and 2015 recorded survivorship and growth across 2,419 coral colonies placed on reefs throughout the sanctuary, finding that survivorship among the longest monitored cohorts ranged from as low as 4 per cent to as high as 89 per cent depending on the site and conditions. That range mattered because it gave restoration groups in the Caribbean and Pacific real-world evidence to build on instead of guesswork about which reef sites and outplanting techniques worked best.
An AI-generated image shows a diver securing a staghorn coral fragment to an underwater nursery structure, where it can grow before being transplanted to a damaged reef. Credits – Google Gemini
From one nursery to a global reef restoration movementThe strategy became better known as the work expanded. In 2012, CNN named Nedimyer a CNN Hero for his coral-restoration efforts. By 2022, the Coral Restoration Foundation had planted more than 200,000 corals, according to NPR, and restored colonies at sites such as Carysfort Reef had begun reproducing naturally. That reproduction offered evidence that nursery-grown corals could become part of functioning reef communities rather than remaining isolated restoration plots. The Coral Restoration Foundation also publishes further detail on that ongoing restoration work.Later Nedimyer helped manage Reef Renewal International, an institution that has since spread the coral tree model far beyond Florida, supporting nurseries in Bonaire, Curacao, Saint Vincent, the Cayman Islands, Hawaii, French Polynesia and Australia. What started as a few pieces of coral hanging from his dock in the Florida Keys are now routine techniques at reef-restoration sites in three oceans, a result of a project launched because a teenager needed something to turn in for school.
