SANTO DOMINGO, Dominican Republic – The Dominican Republic lies in the natural path of the sargassum that flows into the Caribbean from the Atlantic, covering beaches, polluting ecosystems, and impacting tourism. And, despite the magnitude of the crisis expected by 2025, innovation and collaboration are opening new opportunities to transform this threat into raw materials for bioproducts, fertilizers, construction , and clean energy.
Last June was the worst month of the year, with a record-breaking 37.5 tons of seaweed deposited, according to the University of South Florida (USF) bulletin on July 1. Although levels remain high, a slight downward trend is already being observed, offering some relief to the coasts.
“This has been the worst June since we began monitoring in 2011,” said Dr. Chuanmin Hu, director of the Optical Oceanography Lab at USF, in the official bulletin of the Sargassum Watch System (SaWS). “Sargassum levels may decrease slightly in the coming months, but they will remain above the historical average.”
Although the Hotel and Tourism Association – Asonahores – has not published exact figures on occupancy losses related to sargassum, in a 2023 interview Andrés Marranzini acknowledged that “when the volume of sargassum is high, visitor complaints increase and the experience is affected, especially among European and North American clients.”
The organization estimates that daily beach cleaning represents an expense of between US$ 30,000 and US$70,000 per month , especially when they have to hire additional staff, install marine barriers, or implement nighttime collection.
The trigger
The cause of this phenomenon is directly related to global warming . According to reports from USF and other scientific sources, the water temperature El Niño , has created ideal conditions for the proliferation of the Great Atlantic Sargassum Belt (GASB ), which stretches from Africa to the Gulf of Mexico.
It's important to remember that sargassum thrives on the excess nutrients that flow into the ocean from rivers like the Amazon and the Mississippi, many of which are the result of intensive agricultural practices. This combination creates a perfect storm that transforms the Caribbean into a funnel of algae, appearing earlier and denser each year.
What's at stake?
The sargassum invasion is impacting multiple dimensions of national life, and so far this year the most affected coasts are La Altagracia (Punta Cana, Bávaro, Uvero Alto), La Romana, Samaná, and some areas of Barahona and Pedernales. All of these are tourist destinations.
Main impacts:
• Tourism : Overcrowding on beaches reduces the quality of the coastal landscape and leads to hotel cancellations, especially from European and North American tourists. Hoteliers estimate losses of up to 15% in occupancy in some areas during the first half of the year.
• Public health : Bad smells aside, the decomposition of sargassum emits hydrogen sulfide, a gas that causes headaches, nausea and respiratory irritations, especially in vulnerable people.
• Marine ecosystems : The shadow cast on the sea by the floating island prevents photosynthesis of corals and seagrass and reduces the oxygen in the water, causing fish mortality.
• Fishing and livelihoods: Coastal communities report decreased catches due to habitat alteration and navigation difficulties caused by floating masses.
Science to make magic
Universities, coastal communities, and businesses in the Dominican Republic and other Caribbean countries have joined forces with scientific will, public investment, and social commitment to transform an environmental problem into a platform for sustainable development.
Among the initiatives involving the academic, business and community sectors that take advantage of sargassum, SOS Carbón open sea collection system known as LCM (Littoral Collection Module) .
Dried seaweed is transformed into fertilizers, agricultural biostimulants, and exported to more than ten countries for use in cosmetics, bioplastics, and other industrial sectors.
Another significant example is the Punta Cana Group Foundation , which works with fishing communities to collect sargassum before it reaches the beaches and processes it into compost for sustainable agriculture . In partnership with the Canadian embassy, they have developed a model that incorporates women and fishermen into the sargassum value chain, although the exact tonnage they process annually has not been published.
AlgeaNova, an operating company in Punta Cana, is developing processes to convert sargassum into food products, cosmetics and energy materials, while Blue Green, with its Sargablock building block (40% sargassum + 60% organic matter), plans to open production facilities in the Dominican Republic.
Hope in academia
Faced with the magnitude of the threat and with the aim of scaling up solutions and integrating them into local production chains, articulating science, innovation and circular economy, the country is responding with applied research, through the Technological Institute of Santo Domingo (INTEC) , which launched the " Sargassum 2025" call in January, with the aim of financing scientific solutions to the problem.
The initiative, coordinated by the Inter-University Network for Sargassum Research (SARGARD) , received RD$59.2 million in funding from the Presidency of the Republic to select and execute between 5 and 7 high-impact projects, with a limit of RD$10 million per proposal.
were submitted from ten academic institutions, including PUCMM, INTEC, UFHEC, UNPHU, UNISA/ISA, UNIBE, UCATECI, UNAPEC, UASD, and UTESA, which presented the following topics:
• Early detection systems for sargassum in the open sea
• Development of smart barriers and collection technology
• Production of biofuels, fertilizers, bioplastics and cosmetics
• Solutions with a focus on circular economy and community participation
Although the evaluation process concluded in May, the list of winning projects has not yet been published, generating anticipation among researchers and coastal communities. “There are good ideas on the table, but we need to move from theory to implementation. As we can see, the crisis doesn't allow for delays,” commented an academic source close to the evaluation committee.
INTEC has also made progress in research exploring the production of activated carbon, biopolymers, biostimulants, and biofuels from sargassum. This research is being conducted at a pilot scale, and while there is still no industrial processing plant, its trials have served as a scientific basis for the projects submitted to the national call for proposals “Sargassum 2025.”
The challenge is structural
Faced with the persistent arrival of sargassum, the country is moving towards sustainable solutions and has begun to transform this threat with a comprehensive approach, from the marine collection carried out by SOS Carbón in Punta Cana, to the community composting projects promoted by the Grupo Puntacana Foundation, and the applied research of INTEC to convert the seaweed into bioproducts.
Although the challenge is ongoing, the efforts combine innovation, science, and local participation, reflecting a strategy that recognizes that sargassum will not disappear, but can be managed and harnessed for the benefit of the environment and the economy.
Scientists and communities have accepted it: sargassum is not a passing phenomenon, but a new structural element of the climatic and environmental reality of the Caribbean, and in this scenario, the key will not only be how to clean the coasts, but how to learn to live with sargassum, mitigate its impacts and take economic, scientific and social advantage of it.
