On a golden day last September, I visited the ruins of the first Greek city on the Iberian Peninsula, a settlement from the sixth century B.C. called Empúries. Traders venturing down present-day Spain’s Costa Brava, a rugged stretch of coastline in northeastern Catalonia, had recognized the advantages of the location: a natural port, some protection from the fierce tramontana winds blowing off the Pyrenees, and access to local trade networks established by native Iberians. But as the Greek settlers discovered, another attribute of their new home lay just offshore.
As the archaeologist Elisa Hernández and I walked the shadeless grounds of Empúries, she pointed out the stone remnants of temples, public squares, homes of wealthy merchants, and humble dwellings of the poor. Throughout the ruins, archaeologists have found vivid bits of red coral, likely handpicked by free divers along the rocky coastline. In a laboratory of the Empúries branch of the Archaeology Museum of Catalonia, located just at the edge of the site, Hernández emptied a fat plastic bag of these collected pieces onto a lab table, tiny remnants of the branching vermilion animals that once flourished across the Mediterranean Sea.
Mediterranean peoples’ connections to red coral stretch back to Paleolithic hunter-gatherers, who collected the fragments that washed up on beaches after storms. In the past, as now, red coral was valued for its beauty, and in many cultures it is still believed to have protective and curative powers. The Greeks even gave red coral its own creation myth: Its wavy branches were said to have formed from the blood of Medusa, the snake-haired Gorgon, after she was cursed by the goddess Athena and beheaded by the Greek hero Perseus.
As red coral became a sought-after material for jewelry, currency, and religious ceremony, the Greeks, the Romans, and, later, others established extensive coral-trading networks that eventually reached India, East Asia, the Middle East, West Africa, and elsewhere. Long after Empúries faded into the dunes, coral harvesting along the Costa Brava continued—by free divers, by boats fitted with crude, destructive dredges, and in recent decades by specialized scuba divers who can collect coral from otherwise inaccessible caves and small crevices. Until recently, this rugged Catalonian coast remained an important center of coral collection and trade. Here, as in the red-coral-fishing communities that range from France, Italy, and Croatia to Morocco, Algeria, and Tunisia, the species is an enduring element of local culture.
Red coral is no longer bountiful, though: It’s threatened not only by over-harvesting but also by habitat destruction and climate change. Saving the species requires an international effort as complex and innovative as those ancient trading networks, one that values red coral for both its aesthetic splendor and its role in supporting entire Mediterranean ecosystems.
One early morning this past fall, I crossed the French border about an hour north of Empúries to meet Lorenzo Bramanti, who studies coral ecology at the Oceanological Observatory of Banyuls-Sur-Mer. Bramanti has been scrutinizing the earliest life stages of red coral, part of an effort to give coral larvae the best chance to survive and propagate.
Bramanti and I drove along the winding coastal road that borders the Cerbère-Banyuls marine reserve—an area rich in biodiversity just north of the Cap de Creus, the peninsula where most of Catalonia’s red-coral harvesting historically occurred. Seagrass meadows in the reserve provide a nursery for species like seahorses and octopuses; rocks shelter mollusks, crustaceans, and fish. The reserve protects what is known as a coralligenous habitat, where red coral and other non-reef-building corals anchor themselves to a rocky structure made from the accumulated skeletons of algae and small animals.
“This is my underwater laboratory,” Bramanti told me cheerfully. It was easy to understand his enthusiasm: Protected since 1974, this reserve is a candy shop for a coral scientist, offering a rare chance to see what long-term conservation can do for the health of red coral and other species.
We descended into the village of Banyuls, nestled between the sea and the foothills of the Pyrenees. The rivers that rush down from the mountains carry nutrient-laden sediments into the sea, and the tramontana winds create an upwelling effect, pulling deeper, colder, nutrient-rich seawater to the surface. This means that red coral flourishes here in a relatively shallow 50 to 65 feet of water. “If you dive here, you find that the water is always turbid. Full of food. The corals eat a lot,” Bramanti said.
Bramanti’s work revives an old tradition of coral research in Banyuls. Henri de Lacaze-Duthiers, a French zoologist, founded the lab in 1881 after decades of studying the sea life of the western Mediterranean. In 1864, he published the first monograph on red coral, whose scientific name is Corallium rubrum. Bramanti still uses Lacaze-Duthiers’s exquisite drawings and painstaking notes to help him understand the species.
Bramanti has studied corals in his native Italy as well as in Spain, California, and the Caribbean. Since arriving in Banyuls four years ago, he has focused his attention on the first years of C. rubrum’s life cycle, when the coral transforms from tiny larvae into branching treelike creatures.
The coral derives its intense, enduring red color from carotenoid pigments, which play a role in the photosynthetic processes of the tiny plants that form part of C. rubrum’s diet. When people think of red coral, they often picture its deep ruby branches, polished to a vibrant glow, that are worn as jewelry. In life, however, those calcium-carbonate branches support a colony of tiny animals called polyps.
When undisturbed, the coral’s polyps emerge from the skeleton like semi-translucent flowers, pushing through the skin-like tissue that covers the branches. Their eight tiny tentacles, fluttering ever so gently with the current like fine dandelion fuzz, usher plankton and other organic matter into each polyp’s central mouth and transport it through the outer tissue to nourish the entire colony.
Each year in July, the polyps in a male coral colony—a colony’s polyps are either all male or all female—excrete sperm. If they’re lucky, the sperm find their way to a female colony and fertilize its eggs. The fertilized eggs develop into larvae, and after a few weeks the larvae are released into the ocean currents. Most of them don’t survive, but a lucky few will land on a rocky surface—ideally in a protected crevice, cave, or overhang.
Once they’ve found a home, each larva metamorphoses into a polyp, which then reproduces asexually to create new, genetically identical polyps. These polyps, in turn, spit out tiny particles called sclerites that slowly accumulate to form a mound from which the calcium-carbonate skeleton can grow. Once mature, the polyps on the growing skeleton will produce either sperm or eggs, beginning the cycle again.
In his seaside office, located just a few yards from the observatory’s dock, Bramanti described the process of diving to collect coral specimens just before female polyps release their larvae. In his lab, down the hall from his office, he studies the newly liberated larvae under a microscope as they settle, become polyps, and slowly begin constructing hard skeletons.
By the time a coral colony reaches sexual maturity, from six to 10 years old, its skeleton is still just a red nub about the height of a thumbnail. It needs as much as a century to develop into the magnificent branching structure that plays such a crucial role in its ecosystem.
If the colony can survive that long, that is. Even in many marine protected areas, red-coral colonies remain vulnerable to harvesting.
In shallow waters, coral fishers have already removed most of the older, larger colonies. Those that remain are tiny, many only a few inches tall and lacking the intricate branches that today fetch exorbitant prices.
Yet in most parts of the Mediterranean, the harvest continues: Under guidelines established by the United Nations Food and Agriculture Organization (FAO), it is still legal to harvest colonies with a basal diameter of seven millimeters or larger. Tiny though that may seem, a colony with a “trunk” of that size could be 30 or 40 years old, Bramanti said. And poachers take colonies of any size, because even tiny pieces can be turned into composite products, or ground into powder believed to possess medicinal properties. Harvesting pressures are contributing to smaller average colony sizes.
Bramanti and other researchers frequently compare red-coral colonies to a forest. Like trees in a forest, the colonies create three-dimensional complexity in the environment, providing shelter and camouflage to other species. Trees affect wind currents; corals affect ocean currents. These branching “animal forests” provide services that a multitude of species depend on.
Or, at least, they did. In too many parts of the Mediterranean, these functions have been lost because the corals have either disappeared or are too small to provide meaningful ecosystem functions. It might be too late to fully understand the impacts: Scientists don’t know the potential of C. rubrum’s role in ecosystems because they cannot study the kinds of large, pristine populations that were prevalent in the past.
“With the red coral, we have microforests. We have, like, fields, not forests,” Bramanti explained. He and his colleagues speak of the transformation of coral forests to “grasslands.” As with so many other wondrous creatures, humans have nearly loved the red coral to death.
Serious efforts to manage the Mediterranean’s red-coral fishery didn’t commence until the late 1970s, after harvests peaked and began to fall. By the early 1980s, data revealed a steep drop in yields.
In 1987, Spain unsuccessfully attempted to list red coral under CITES, the Convention on International Trade in Endangered Species; two decades later, successive attempts by the United States and the European Union failed to list the species. All of these efforts faced concerns about the difficulty of implementing and enforcing trade controls; they were also opposed by industry representatives who argued that local management could still be effective.
Georgios Tsounis, an adjunct professor of marine biology at California State University Northridge who serves as a technical adviser for the intergovernmental General Fisheries Commission for the Mediterranean (GFCM), says local management is too often underfunded and vulnerable to political pressures. He thinks continued development of international solutions is also necessary.
Tsounis believes that the previous CITES attempts have laid solid groundwork for a potential future listing. They also have raised public awareness and helped spur new research and management strategies. A decade after the last attempt, Tsounis would like to see the evidence for a CITES listing revisited as international demand continues to drive soaring prices that incentivize illegal coral fishing and trafficking. Without border controls, this remains difficult to combat. “The term red gold becomes increasingly more justified,” he told me.
Progress on other management strategies also remains slow. In the 1980s, the FAO established some basic guidelines for national regulation of red-coral harvests. An EU dredging ban followed in 1994, though some poachers continue the destructive practice. Spain, France, Italy, and other European countries, as well as North African nations like Morocco, Tunisia, and Algeria, began applying restrictions on coral fishing in over-exploited shallow waters.
The GFCM established an adaptive management plan for red coral in 2017. Whereas coral management had historically prioritized industry needs—for example, by compromising with industry on biologists’ recommendations for minimum size and collection depth—adaptive management integrates more ecological data into decision making.
But so far, scientists are still waiting for more detailed data.
What’s needed, Tsounis said, is information that goes beyond the total tonnage of red coral harvested. Scientists would like more specific data about where coral has been collected. And they want to know not just the minimum, but also the maximum, colony size harvested in a given location. Much of this “fishery-dependent” data is already being gathered by coral fishers and local fishery managers, but in order for it to be useful to coral conservation it needs to be standardized across the region—something the GFCM is working on. “It’s an opportunity to really improve the management when we get this fishery-dependent data,” Tsounis said.
In 2017, the regional government of Catalonia imposed a 10-year red-coral-fishing moratorium in its waters following a report that illustrated the dire situation of the species in shallow waters off Costa Brava. The Spanish government announced its own two-year, extendable moratorium in 2020 while new conservation strategies are studied.
But even the most protective conservation laws are ineffective without adequate enforcement, funding, and international coordination, says Joaquim Garrabou, a leading red-coral researcher at the Institute of Marine Sciences (ICM) in Barcelona. Two years into the Catalan moratorium, poaching and trafficking continue, just as in other coral-rich parts of the Mediterranean. High prices create irresistible incentives, even in the face of restrictions. One case in point: Tunisian authorities seized 671 kilograms of illegally harvested red coral—worth 2 million euros—and arrested 10 people on suspicion of trafficking, the Agence France-Presse reported in 2019. “The market is there,” Garrabou said.
With limited patrols charged with covering vast areas of ocean, it’s difficult for law enforcement to be in the right place at the right time to catch coral poachers. Even when cases make it to trial, said Garrabou, the burden of proof is high and penalties generally small, so many find poaching a risk worth taking.
Garrabou believes that stronger penalties coupled with robust funding for enforcement and criminal investigations would significantly decrease illegal harvesting and black-market trade. Every action counts, because there’s another threat that’s even harder to control: As policy makers fret about fishing, climate change is rapidly altering the Mediterranean Sea.
In the summer of 2003, Europe was gripped by a deadly, unrelenting heat wave. Above-normal temperatures descended on the United Kingdom, France, Spain, and Italy, extending north to Scandinavia and east to Russia. Wildfires raged in France, Spain, and Portugal; ancient permafrost melted in the Alps, triggering massive rockslides.
Then things got worse. The old and the ill succumbed to heat exhaustion and dehydration. By the end of the summer, the prolonged record-breaking heat had claimed more than 30,000 lives, and countries were forced to reckon with their lack of preparation.
At the same time, global warming was unleashing another, more hidden, catastrophe. Few of the vacationers who fled sweltering cities for Mediterranean beaches knew that a mass-mortality event was occurring just under the surface of the sea, where temperatures spiked 1 to 3 degrees Celsius above the average, resulting in the warmest water ever recorded in some areas.
It wasn’t the first severe marine heat wave to strike the Mediterranean. In 1999, another sudden warming event had led to mass mortalities in the waters off the French and northern Italian coasts. In both heat waves, temperatures were so far outside the normal seasonal range that they caused severe physiological stress in red-coral colonies.
Under these conditions, colonies can succumb to usually harmless bacteria that cause disease in coral only above certain temperature thresholds, suffering total or partial death of the living tissue covering their skeletons. Over time the most severely affected colonies break off at the base, leaving no trace. Heat waves also diminish larvae’s ability to survive and settle, in effect killing off the next generation.
By 2003, Garrabou had spent nearly a decade studying a stunning coral population in the Scandola marine reserve off Corsica. Located in an underwater cave, the lush, colorful population of huge red colonies gave scientists some idea of what the Mediterranean’s coral must have looked like before intense harvesting. After the heat wave, though, the cave became a scene of devastation.
“It’s like you found this really nice place to go and take a walk, and then there is a forest fire and you go back there and there is no more color,” Garrabou told me. Everything had been transformed into a dull gray-brown.
In the decade before 2003, Garrabou’s team had placed markers next to corals so they could collect data year after year. Fellow scientists who later accompanied Garrabou found the markers, but no coral. “Then I showed them the pictures taken before 2003, and they understood the magnitude of the change and why we put the marks there. Because there were a lot of red coral. Colonies that are now simply gone.”
Garrabou had expected to witness a comeback of the Scandola population at some point. But the 2003 heat wave was followed by others in 2006 and 2009, and again in 2010, 2016, and 2018. Today, he estimates that this red-coral population has decreased by between 80 and 90 percent. “For us it’s like seeing a terminal patient,” he said.
The heat waves in the Mediterranean Sea are part of a global trend. A 2018 study published in Nature Communications found that from 1925 to 2016, the global average frequency of marine heat waves rose by a third, while their duration increased by 17 percent. Over the past century, there has been a 54 percent increase in annual marine heat-wave days.
Globally, the ecological and economic impacts of recent marine heat waves are sobering: rapid changes in the range of certain species, die-offs of species that could not migrate or otherwise respond, and restrictions and closures of important fisheries. In the Mediterranean, marine heat waves have elevated average sea temperatures at an alarming rate. Mass-mortality events are increasing and have affected dozens of species, including seagrasses, sponges, and several other coral species—resulting in ripple effects for the fish and other organisms that depend on them.
In addition, there is the wild card of ocean acidification, which hinders the ability of red coral and other marine species to construct calcium-carbonate skeletons and shells. Estimates suggest that acidity in the Mediterranean Sea increased by more than 10 percent from 1995 to 2013 alone. While marine warming is a more immediate concern, Garrabou said, acidification could have synergistic effects that further damage red-coral populations.
Even if someone could wave a magic wand and suddenly halt the impacts of climate change, damaged corals wouldn’t recover overnight. Aiding the recovery of red coral through direct transplantation has shown promise on a local scale, said Garrabou, but it is not a large-scale solution. Researchers have successfully transplanted a few poached red-coral colonies that were still living when law-enforcement agents intercepted harvesters. Other experiments have involved taking fragments from “donor” colonies—for example, colonies that have shown a resistance to marine warming—to support restoration in shallow coastal waters. Such actions have been effective for some fast-growing tropical corals. But for slow-growing species like red coral, even assisted recovery could take decades.
Scientists are investigating other ways of increasing red coral’s chance of survival. In Banyuls, Bramanti is trying to pinpoint the optimal conditions for larvae establishment and endurance. To replicate those conditions, he’s experimenting with what he calls “coral hotels”: cement boxes that simulate protective caves and crevices.
First, Bramanti genotypes a group of small, sexually mature male and female colonies. Then he slides up to nine removable ceramic tiles, each containing one colony, onto the ceiling of the boxes. Several boxes are arranged in a hexagonal shape on the sea floor so he can investigate factors like the best ratio of male colonies to female colonies, and the optimal distance for fertilization.
Once fertilization occurs, Bramanti removes some female colonies and takes them to the lab, where, rather like an expectant father, he observes the release of larvae. “Then a universe opens,” he said.
With special cameras and microscopes, he observes the larvae as they move and settle. After settlement, he continues monitoring the development to understand which conditions and interventions best support survival in this vulnerable time. “If you can save them during this period, when they are stronger they can go back to the wild,” he said, and have a greater chance of success.
To fight poaching and trafficking, scientists are developing molecular tools that can identify illegal coral harvests. Jean-Baptiste Ledoux, an assistant researcher based in Portugal at the University of Porto’s Interdisciplinary Centre of Marine and Environmental Research, integrates population genetics, genomics, and experimental ecology to study coral conservation. He previously worked with Garrabou at the ICM to identify distinct genetic groups of C. rubrum from colonies located in two Costa Brava hot spots: the Medes Islands and Cap de Creus.
Ledoux and his colleagues will soon be able to apply even more precise forensic analyses to red- coral-fishing enforcement and conservation. In November of last year, the Catalan Biological Society announced funding to sequence the entire red-coral genome.
The project, led by Garrabou at the ICM, is a huge development. Ledoux will coordinate research between the institutions involved in decoding red coral’s complete genetic instructions. This will help scientists advance the development of powerful genetic tools to help law enforcement catch poachers and strengthen criminal evidence against them.
Similar molecular forensic techniques have helped combat ivory poaching by genetically identifying the origin of intercepted ivory and beefing up enforcement to protect targeted elephant populations. The same could be done for red coral. And if C. rubrum eventually receives a CITES listing, these tools could be deployed at international borders.
Ledoux says genomic sequencing will allow scientists to explore in more detail the genetic factors that increase resilience—for example, why some coral populations are less affected by marine warming—so they can be targeted for restoration.
“Having the genome sequence of the red coral will open new avenues for its conservation and restoration as well as for policy, enforcement, and the struggle against poaching,” he told me. “This is potentially a giant step for the conservation of the species.”
Well-managed marine protected areas are also essential to conservation. Not only do they give coral a chance to grow by restricting fishing, but they allow researchers to do long-term monitoring of relatively undisturbed coral populations.
Currently, only 6 percent of the Mediterranean Sea is protected at all, with less than 1 percent designated as highly protected. Any serious efforts to save red-coral colonies, Garrabou said, must involve expansion of marine protected areas—and enforcement—across the entire region.
Scientists and conservationists recognize that effective enforcement must enlist the support of local communities, whose residents run the fishing and recreational-diving businesses that can damage coral populations.
Eighteen miles south of Empúries, in the medieval fishing village of Begur, the tradition of coral harvesting remains embedded in community identity and the local economy. From the 14th to 19th century, Catalan coral fishermen set out from Begur’s crystalline coves to collect coral both locally and down the coasts of Spain and North Africa. Upon their return, traders transported the harvest to the Italian centers of coral craftsmanship: Genova, Trapani, and, later, Torre del Greco, which remains the heart of the red-coral-jewelry industry.
In Begur’s grand central church, an ethereal sculpture depicts a Virgin of the Coral with flowing hair and gown, holding at her hip a child clutching a crimson coral branch. Here, generations of women prayed for the safe return of their fishermen; some of their descendants still wear bits of coral around their necks or keep some in their homes for protection and good health.
Today, Begur and nearby L’Estartit maintain economic connections to coral. Some 60,000 recreational dives a year occur in the nearby Medes Islands, a marine reserve whose relatively healthy corals are a big tourist draw. The success of the diving industry here represents yet another threat to vulnerable marine organisms, because divers can accidentally break off coral colonies—and, in some cases, tourists illegally collect them as souvenirs. But Joaquim Garrabou told me there’s also an emerging opportunity for local fishers, divers, and scientists to team up and protect imperiled species.
Garrabou coordinates a project called Sea Watchers, an international network of researchers, industry leaders, and community members that incorporates local observations and expertise into marine monitoring and research.
The project also facilitates training for diving companies so they follow best practices to protect fragile ecosystems and educate tourists about vulnerable species like red coral. Dive clients can participate directly in citizen science, identifying and documenting red coral and other species through underwater photography, for example, that is shared with scientists.
Fishers with a lifetime of experience at sea are helping researchers identify, map, and collect data on coral populations, contributing to a more complete picture of the corals’ demographics and health. Fishers respond positively when their expertise is valued and included in decision making, Garrabou said. “The top-down approach maybe can work for some issues, but when we have to deal with this transformation of our society, it has to be really understood by the people; otherwise, the implementation is not efficient or effective at all.”
After my visit with Bramanti in Banyuls, the two of us headed back over the Spanish border to Cadaqués, an isolated fishing village just beyond the rugged Cap de Creus. Bramanti was there for dive-safety training facilitated by Toni Garcia, a former coral fisher and the proprietor of the Diving Center Cadaqués. Garcia has worked with Bramanti for years, providing logistical support for scientific dives and introducing him to local fishers.
Garcia’s own father was a fisher in Cadaqués in the 1970s, during the last golden age of coral fishing there. Garcia returned to Cadaqués in the early 1990s and started the dive center, working as a commercial diver and spending summers harvesting coral.
Garcia is an example of a coral fisher with his “foot in two shoes,” Bramanti said. When they met in the mid-2000s, the two men bonded over a shared passion for diving. As Garcia accompanied Bramanti and his colleagues on dives, he came to embrace sustainable, science-based fishing policies.
Coral fishing “has been the most beautiful job I’ve had in my life, and I would do it again, without a doubt,” Garcia said. “But surely with a different perspective, more conservation-minded.”
Bramanti, Garrabou, and other prominent coral researchers are convinced that this kind of community stewardship is crucial to any effective conservation effort. The more opportunities people have to participate in science, the more likely they’ll be to protect the coral.
Back at the Banyuls-Sur-Mer observatory, Bramanti paused at a small glass case to point out a bright red-orange coral skeleton, thick with branches, about 11 inches wide by 7 inches tall. The display described it as a 300-year-old colony harvested at a depth of 90 meters, or almost 300 feet.
The colony was collected in 2002 by a Cadaqués fisher whom Bramanti met through Garcia. Bramanti had been searching for a small specimen to study and was willing to pay for it. But the fisher insisted on donating the entire colony to the observatory. Bramanti estimated that it is worth close to $3,000.
“At the end of your career you realize you’ve killed a lot of these super-beautiful animals,” Bramanti said, referring to the fisher. “You get old, and you realize. And you want to give something back.”