The environmental threats faced by both island nations in the Caribbean Sea and the mainland Caribbean basin are not limited to just hurricanes. Currently, massive waves of a golden, toxic seaweed called Sargassum are threatening not only the tourism industry—which is a large part of the region’s economy—but also the fishing industry, the health of residents, and sea wildlife.
The Sargassum problem is not a new one. However, in recent months the amount of the algae—which floats in huge beds unattached to the ocean floor before piling up on the beaches and creating a malodorous smell—along with the potential health hazards for those people who have to work in those waters has increased.
Caribbean Matters is a weekly series from Daily Kos. If you are unfamiliar with the region, check out Caribbean Matters: Getting to know the countries of the Caribbean.
As a refresher, Encyclopedia Britannica offers this description of the geographic region that comprises the Caribbean Sea—too many of us forget that the Caribbean region encompasses far more than the islands of our dream vacations.
It is approximately 1,063,000 square miles (2,753,000 square km) in extent. To the south it is bounded by the coasts of Venezuela, Colombia, and Panama; to the west by Costa Rica, Nicaragua, Honduras, Guatemala, Belize, and the Yucatán Peninsula of Mexico; to the north by the Greater Antilles islands of Cuba, Hispaniola, Jamaica, and Puerto Rico; and to the east by the north-south chain of the Lesser Antilles, consisting of the island arc that extends from the Virgin Islands in the northeast to Trinidad, off the Venezuelan coast, in the southeast.
Within the boundaries of the Caribbean itself, Jamaica, to the south of Cuba, is the largest of a number of islands.
And here’s how the National Oceanic and Atmospheric Administration’s (NOAA) Ocean Exploration division describes Sargassum.
Upon close inspection, it is easy to see the many leafy appendages, branches, and round, berry-like structures that make up the plant. These “berries” are actually gas-filled structures, called pneumatocysts, which are filled mostly with oxygen. Pneumatocysts add buoyancy to the plant structure and allow it to float on the surface.
Floating rafts of Sargassum can stretch for miles across the ocean. This floating habitat provides food, refuge, and breeding grounds for an array of animals such as fishes, sea turtles, marine birds, crabs, shrimp, and more. Some animals, like the sargassum fish (in the frogfish family), live their whole lives only in this habitat. Sargassum serves as a primary nursery area for a variety of commercially important fishes such as mahi mahi, jacks, and amberjacks.
NOAA is also an excellent source for information on the Sargasso Sea, which is home to multiple types of Sargassum.
While there are many different types of algae found floating in the ocean all around world, the Sargasso Sea is unique in that it harbors species of sargassum that are 'holopelagic' — this means that the algae not only freely floats around the ocean, but it reproduces vegetatively on the high seas. Other seaweeds reproduce and begin life on the floor of the ocean.
Sargassum provides a home to an amazing variety of marine species. Turtles use sargassum mats as nurseries where hatchlings have food and shelter. Sargassum also provides essential habitat for shrimp, crab, fish, and other marine species that have adapted specifically to this floating algae. The Sargasso Sea is a spawning site for threatened and endangered eels, as well as white marlin, porbeagle shark, and dolphinfish. Humpback whales annually migrate through the Sargasso Sea. Commercial fish, such as tuna, and birds also migrate through the Sargasso Sea and depend on it for food.
While all other seas in the world are defined at least in part by land boundaries, the Sargasso Sea is defined only by ocean currents. It lies within the Northern Atlantic Subtropical Gyre. The Gulf Stream establishes the Sargasso Sea's western boundary, while the Sea is further defined to the north by the North Atlantic Current, to the east by the Canary Current, and to the south by the North Atlantic Equatorial Current. Since this area is defined by boundary currents, its borders are dynamic, correlating roughly with the Azores High Pressure Center for any particular season.
Here’s a great visual of the Sargasso Sea:
While this sea of Sargassum is an important natural resource, it is also a major hazard. The Caribbean Coastal Ocean Observing System (CARICOOS) Laboratory of Optical Oceanography of the University of South Florida’s School of Marine Sciences has a floating Algae Index, which provides a great visual resource to track the problem as it intensifies. It shows images of Sargassum on the coasts in real time.
Recent Associated Press reporting highlights the crisis. In the video below, Marlon Jones, a resident of Barbados who lives just 800 meters from the beach, notes that “the stench is unbearable, especially at night.”
As AP Caribbean correspondent Dánica Coto writes:
More than 24 million tons of sargassum blanketed the Atlantic in June, shattering the all-time record, set in 2018, by 20%, according to the University of South Florida’s Optical Oceanography Lab. And unusually large amounts of the brown algae have drifted into the Caribbean Sea.
The concentration of algae is so heavy in parts of the eastern Caribbean that the French island of Guadeloupe issued a health alert in late July. It warned some communities about high levels of hydrogen sulfide gas emanating from the huge rotting clumps of seaweed. The gas, which smells like rotten eggs, can affect people with breathing problems such as asthma.
The Biden administration declared a federal emergency after the U.S. Virgin Islands warned last month of unusually high amounts of sargassum clogging machinery at a desalination plant near St. Croix that is struggling to produce water and meet demand amid a drought.
Mexico News Daily focuses on potential health risks from the rotting seaweed.
When large quantities of sargassum decompose, gases such as hydrogen sulfide – which has a rotten egg smell – methane and ammonium are generated, said Brigitta Van Tussenbroek, a researcher at UNAM’s reef systems unit in Puerto Morelos.
“The one of greatest concern is hydrogen sulfide,” she said, explaining that chronic exposure to the gas can cause health problems, “mainly for people who have respiratory problems.”
According to the United States Agency for Toxic Substances and Disease Registry (ATSDR), “just a few breaths of air containing high levels of hydrogen sulfide can cause death.”
“… Exposure to low concentrations of hydrogen sulfide may cause irritation to the eyes, nose, or throat. It may also cause difficulty in breathing for some asthmatics,” the ATSDR said. “… Exposure to low concentrations … may cause headaches, poor memory, tiredness, and balance problems,” it added.
The Centre for Resource Management & Environmental Studies (CERMES) at the University of the West Indies, Cave Hill Campus in Barbados conducts ongoing Sargassum research.
[Over a] decade has passed since misfortune first struck overnight. Caribbean people woke from their slumber to see their coastlines and nearshore waters mysteriously inundated with floating rafts and piles of sargassum seaweed - leaving widespread environmental and economic outfall in its wake.
The seaweed continues to besiege us, but our team in Barbados like many others across the region have sought to communicate the science as it unfolds; to fill in gaps of knowledge through innovative research, provide guidance for better management and ultimately make the best of the mangling mess - reframing it as an opportunity to expand scientific knowledge and foster innovation.
CERMES’ collection of Sargassum research stories can be found here. For some of the history and impact of the influx of the algae, check out this very short film, Sargassum: The Golden Tide, which was produced in 2018. The visuals are stunning and horrific, even as the narrator offers glimpses of hope and opportunity.
(More on that opportunity in a moment.)
As CERMES writes on YouTube:
In 2011, 2014, 2015, and in 2018, thousands of tons of pelagic sargassum seaweed, referred to as sargassum influxes, have piled up to 3 metres thick on beaches and in the nearshore waters of many Caribbean states and territories. These events have triggered much consternation regionally about state, civil society and private sector capacities to cope and adapt. There has been concern, including among inter-governmental organisations, about long-term implications for the fisheries and tourism sectors especially, given that such events seem to be a ‘new normal’ due in part to climate change and variability.
The interested parties also realise that sargassum influxes may offer opportunities ranging from agriculture to manufacturing, if the region can support innovation and entrepreneurship. Discussions on marine and coastal policy, management, science and technology at local, national and regional levels about how to deal with a sargassum influx as a new biological natural hazard with the potential for disaster, or as abundant raw material with potential for windfall gains, have considered issues of biodiversity, coastal management, fisheries and tourism livelihoods, foreign exchange earnings, public health, innovation and entrepreneurship opportunities and more.
Reports on the current Sargassum influx can be found all across the Caribbean.
This video report from CGTN’s correspondent Alasdair Baverstock centers tourism and Mexico’s Caribbean coast.
Despite the entrepreneurship opportunities mentioned in Sargassum: The Golden Tide—particularly using the seaweed as fertilizer—Barbados’ leaders are warning against it.
Minister of Environment Adrian Forde is warning those who use the Sargassum seaweed as fertiliser to desist from doing so as it could be harmful.
“The reason why we take it away to decompose away from the environment is because it was viewed there were abnormal levels of arsenic, mercury, and other heavy metals that can be harmful,” Forde said.
More on Forde’s warning in this CBC video:
Saint Barthélemy (St. Bart’s)
Cayman Compass notes that “efforts to use pumps to remove a huge blanket of sargassum from the edge of the North Sound in West Bay have been abandoned after workers found it impractical to pump the rotting seaweed from the water.”
The short video below shows how futile the effort was.
The trial lasted just three days.
This July 26 report from Dominican Today is devastating.
The sargassum situation in the Dominican Republic and the Caribbean region is “critical,” according to José Reyes López, Vice Minister of Coastal and Marine Resources of the Ministry of Environment and Natural Resources.
He warned that rapid action must be taken in relation to the sargassum that is destroying marine biodiversity in the places where it arrives, turtle nesting, fishing communities, obstructing coral reefs and the environmental ecosystem, harming fishing communities, and increasingly impacting the tourism sector.
The Vice-Minister indicated that the sargassum barriers are placed individually in the hotel zones but be assured that it is done with the guidelines of the Vice-Minister of Coastal and Marine Resources of the Ministry.
He acknowledged the work of the barriers but warned that they were not enough and that they only stopped a part of the algae. He said that, in addition, the issue of collection and final disposal of sargassum must be addressed. “That cannot be taken to just any landfill,” he specified. “That is part of the table, not only to prevent the sargassum from arriving, but also the disposal, and also, from that table, to try to find a use for the sargassum. If we don’t find a use for it, we are not going to put an end to it,” he said.
US Virgin Islands (USVI)
A USVI St. Croix resident who vlogs as cruzan mongoose filed this video report from Turner Hole in July 28.
The Sargassum situation has prompted the USVI’s governor to declare a state of emergency.
U.S. VIRGIN ISLANDS — Governor Albert Bryan Jr. issued an Executive Order declaring a State of Emergency in the Territory to mitigate the impact from the unusually high amounts of Sargassum seaweed piling up on USVI shores and having a negative impact on water-production capabilities on St. Croix.
Governor Bryan also has sent a request to the Biden Administration to declare a federal emergency on St. Croix regarding the Sargassum inundation, and teams from the Federal Emergency Management Agency (FEMA) are expected to be on the ground in the Territory on Sunday, July 24, to assist the Government of the Virgin Islands (GVI) in coordinating a response.
Because of the Sargassum build-up, maintenance efforts have increased to keep the water intake for the desalinization plant on St. Croix clear from seaweed and biological debris resulting from the ecosystems associated with large Sargassum blooms. In addition, reduced water production could also create a negative effect on the V.I. Water and Power Authority’s power-generating capacity.
The Biden administration approved Bryan’s application for federal support within days.
FEMA staff visited St. Croix for an in-person assessment of the crisis last week.
Federal Emergency Management Agency (FEMA) Region 2 Administrator David Warrington arrived in the territory on Wednesday, Aug. 3, to make an in-person assessment and get updates on the impact the heavy influx of Sargassum seaweed is having on the V.I. Water and Power Authority’s water production operations on St. Croix.
While water production and capacity have remained at almost normal levels, the joint operation between FEMA and other federal partners and Government of the Virgin Islands (GVI) agencies and departments continue their contingency efforts to mitigate any adverse effects from the seaweed.
As the situation remains manageable, the joint federal and local team has also begun talking about longer-term, more permanent, solutions to avoid future incursions or impacts on water production from the annual migration of Sargassum seaweed into the territory’s waters. “As we continue to face the reality of climate change and its impact on places like the Virgin Islands, FEMA and the entire federal government are going to have to continue working closely with our partners in the Government of the Virgin Islands to innovate and find creative solutions for these new challenges that face us,” Administrator Warrington said.
Across the Caribbean, Sargassum is wreaking dangerous, unsustainable havoc. Viable solutions are necessary to both preserve the biodiversity housed within its massive rafts, and to protect all that it destroys.
The hunt for such solutions continues, from Jamaica to New Zealand to Japan.
Join me in the comments for more, and for the weekly Caribbean News Roundup.