With the coral bank split in half and corals turned to rubble, the underwater world of Laughing Bird Caye National Park, off the coast of Belize, was nothing like the vibrant, colorful place that thrived with life before being swept away by the sea. hurricane Iris in 2001.
The storm left the water turbid and muddy as dead decomposing creatures were washed ashore.
When Lisa Carne first visited the island in 1994, there were so many huge reddish-orange elkhorn corals intertwined that she could barely swim among or around them.
The reef was abundant with fish, corals, lobsters, crabs, sponges and sea turtles. But after the hurricane, all that was destroyed.
With only a few surviving corals, the place looked more like a cemetery.
It wasn’t the first time Carne had seen a dead reef. In 1995, she moved from California to Belize, and worked as a volunteer research assistant at Carrie Bow Cay, a Smithsonian Institution field station.
She witnessed the effects of the first coral bleaching phenomenon in Belize, which is home to the second largest barrier reef in the world.
Bleaching leaves the coral structure intact, but the coral loses the algae that live in an endosymbiotic relationship with its polyps.
Although some corals recover as the algae return, many die.
Hurricane Iris was catastrophic in a different way.
Not only did it kill corals, it also ripped out its structure, making recovery even more difficult.
Carne wanted to immediately start restocking reefs by planting corals, but it took many years to convince funders that his idea was viable.
People argued, and still argue, that without solving the problems that cause corals to die, putting them back on the reef would make no sense.
For five years after Hurricane Iris, the reef was uncovered. There were few live corals, shoals of fish or lobsters, and the sea floor was covered with reef debris and encrusted sponges.
Carne began presenting his restoration proposals in 2002, but for several years he was unlucky.
Then, in 2006, the United States put Caribbean acroporid corals (the fastest growing branched coral type in the Caribbean and a major reef-maker) on the endangered list, and a local funder approved the Carne to Restore project the reef.
Carne began by doing a test, transplanting 19 fragments of elkhorn coral from the main barrier reef some 31 km away.
“People asked me why I was going so far in search of corals,” Carne recalls.
“They thought these corals were common, like sand. But after two weeks of mapping, I found they weren’t everywhere anymore.”
In fact, she found that the structure and cover of corals — which covered 15 percent to 28 percent of the national park area before the storm — had dropped to less than 6 percent.
A series of bleaching cases followed the hurricane, but all was not lost.
Carne noticed that there were pockets in the reef that still looked relatively healthy.
As initial survival from transplants performed in 2006 was high (more than 80% are still alive today), she continued to identify surviving corals and began seeding the reefs again in 2010.
But restoring a reef is not as simple as it may sound and involves trial and error, often with learning along the way.
When scientists started exploring the idea of reef restoration, they thought that the larger the transplant, the greater the chance of survival.
But in 2015, marine biologist David Vaughan found that the opposite could also be true — the smaller the fragment, the faster it grows.
The so-called microfragmentation speeded up the restoration work considerably.
While Carne’s team initially cut the corals into pieces of about 10 cm and grew them in a nursery until they were about 30 cm before transplanting them to the reef, this finding allowed the team to accelerate growth rates in the nursery. for certain coral species and skip this step completely for others.
Carne worked with other researchers in coral genetics, disease, bleaching and reproduction to find the best way to restore the reef.
In 2009, Illiana Baums, professor of Molecular Ecology at Pennsylvania State University in the United States, advised her on the proper distance to plant different specimens of each coral species to encourage spawning (sexual reproduction—which increases genetic diversity and resilience of reefs).
Successful spawning episodes were later documented between 2014 and 2016.
Despite these advances, the task of replanting corals on more than a hectare of shallow reef was too much for a research team of two to four people.
After Carne mapping revealed the extent of damage to the corals, the local population realized how scarce they had become.
Fishermen and tour guides from the nearby village of Placencia were the first to notice the success of the coral transplant efforts, and offered to help Carne with the planting.
In 2013, Carne registered a nonprofit community organization in Belize called Fragments of Hope, and two years later opened a branch in the United States.
Fragments of Hope has developed a coral restoration training course, approved by the Belize Department of Fisheries, which has certified more than 70 Belizeans so far, says Maya Trotz, professor of Civil and Environmental Engineering at the University of South Florida, States United States, and member of the American Board of Fragments of Hope.
The restoration complements the income of the local population from tourism and fishing with restoration work.
“Fragments of Hope engages young people and has created coloring books and puzzles about the reef, featuring art by a local artist,” says Trotz.
“Over 2,500 have been distributed so far to schools in Belize.”
To date, more than 85,000 corals have been planted in Laughing Bird Caye National Park.
Long-term monitoring shows that 89% survived after 14 years—much longer than typical survival after a restoration.
Overall, deep sea coral cover in the park increased from 6% to 50% between 2010 and 2017.
Reports also suggest an upward trend in corals around Belize as a whole, from 11% of the seafloor surveyed in 2006 to 17% in 2018 through natural recovery.
Reef restoration work in Belize is unique because it focuses on shallow reefs – the kind that help protect coastlines – in a sparsely populated area.
With a relatively small population of approximately 420,000, Belize does not exert as much pressure on its reefs as its more populous neighbors.
“I think the key factors in Fragments of Hope’s success are her science-based approach, vast local knowledge, and Lisa’s dedication and persistence,” says Baums.
Belize’s initiatives to protect its reefs also played an important role.
Laughing Bird Caye National Park was founded in 1994.
Belize has banned shrimp trawling, the use of gill nets, the exploitation of offshore oil, and has fully protected fish families that feed on reef algae, such as parrotfish and surgeonfish.
As the only organization that practices reef restoration in Belize, Fragments of Hope has been able to cooperate with the government.
Together they are now working on a national coral replacement restoration plan.
But despite government restrictions, uncontrolled coastal development has destroyed mangrove coral banks in Belize.
There are also plans to build new cruise ports.
“It’s hard to wake up every morning and do what you do when there are bigger decisions being made that you can’t control,” says Carne.
The techniques developed by Fragments of Hope have been successfully applied in Colombia, Jamaica and the Caribbean island of Saint Barts, as well as seven marine protected areas and ten other locations in Belize.
Prior to Covid-19, Fragments of Hope organized exchanges, field trips and workshops to share experiences across the Caribbean.
People learned how to select an appropriate restoration site based on a long list of criteria, set up nurseries, trim corals and use cement for planting.
The organization also shares its methods and experiences online.
“Fragments of Hope is a center of innovation, attracting talent from the Placencia Peninsula and around the world, all inspired by the proactive approach to coral restoration,” says Trotz.
After 15 years of restoration efforts, Laughing Bird Caye National Park’s coral reef, once a graveyard of rubble, is now bursting with life.
Staghorn and elkhorn corals are once again covering the sea floor, reproducing and providing refuge for many species.
Giant lobsters, crabs, eagle rays and sea turtles, which were abundant before the hurricane, now roam the reef.
Schools of parrotfish and surgeonfish have also returned and feed on reef algae so the corals can propagate further.
Scientists, reef restorers and passionate divers all agree that Laughing Bird Caye’s coral reef is unique.
“I haven’t seen this kind of acroporid coverage since the late 1970s or early 1980s. It’s pretty impressive,” says Mark J. Butler IV, professor and researcher at Old Dominion University in the United States, one of the many visitors who went to admire the thriving underwater world of the restored reef.
While the project has had substantial success, maintaining the reef will likely be an uphill battle.
Coral bleaching is becoming more extreme each year due to climate change and more frequent and severe storms.
If greenhouse gas emissions are not controlled globally, few corals are likely to survive in the current scenario.
The bleaching cases in Belize are getting progressively worse, according to Carne.
But if she had waited for zero emissions to begin her work, the reef today might look not much more alive than it did after it was hit by Hurricane Iris.
So while many academics still criticize the idea of restoring reefs in a world of warming oceans, the steady decline of reefs around the world has led to such projects in more than 50 countries — though none have yet come close to the scale or longevity. of the work carried out in Belize.
“When we started, maybe one or two people were doing reef restoration,” says Carne.
“But these days, everyone is doing it. I joke that it’s like yoga now.”