The Brown Tide Returns: Jamaica’s 2025 Sargassum Crisis and the Tourism Economy Under Threat

Briefing

• Caribbean sargassum belt reached 37.5 million metric tons in May 2025, a record.
• Jamaica’s south coast received heaviest inflows; some beaches rendered unusable.
• Hydrogen sulphide released by rotting sargassum triggers health complaints at affected sites.
• Jamaica Tourist Board launches rapid-response cleanup protocol for affected resort areas.
• Researchers propose sargassum-to-fertiliser processing as commercial opportunity.

The satellite data for May 2025 showed a mass of brown seaweed in the Atlantic and Caribbean that measured 37.5 million metric tons — more than triple the volume recorded in any month before 2018, when the Great Atlantic Sargassum Belt first began its pattern of extraordinary annual growth. The researchers at the University of South Florida who track the belt described the 2025 figure as unprecedented. For Jamaica, the numbers were more than academic. They described what was accumulating on the island’s beaches.

Sargassum — a genus of brown macroalgae that grows, without attachment to any seabed, in vast floating mats across the Atlantic — had been arriving on Caribbean coastlines in abnormal quantities since 2011. Jamaica was not spared in earlier years, but 2025 brought inflows to the south coast and parts of the north coast that hotel operators, fishermen, and beach vendors described as qualitatively different from anything they had previously experienced. At some south coast locations, the waterline was buried under several metres of rotting seaweed. The characteristic smell of hydrogen sulphide — produced as bacteria decompose the stranded algae — reached several hundred metres inland at affected sites and generated health complaints from residents and visitors alike.

The Tourism Calculation

For Jamaica’s tourism sector, which contributes more than 10 per cent of GDP and supports hundreds of thousands of direct and indirect jobs, the 2025 sargassum crisis was a significant operational and reputational challenge. The Jamaica Tourist Board activated a rapid-response cleanup protocol that deployed heavy machinery and manual labour teams to resort beach fronts. All-inclusive hotels with substantial resources and organised beach management operations were able to maintain serviceable beach conditions at their frontages, in some cases removing several tonnes of sargassum per day per kilometre of beach. Community beaches, public access points, and the coastlines fronting fishing villages received no equivalent support.

The disparity was stark and visible. Resort guests at major north coast hotels might experience sargassum as a minor inconvenience: a slightly brownish tinge to the water, a smell when the wind came from the shore, reduced visibility for snorkelling. For residents of coastal communities without hotel resources, the 2025 season was a serious economic hardship. Fisherfolk reported that sargassum mats entangled nets and propellers, significantly increasing fuel costs and reducing catch efficiency. Beach vendors and operators of small water-sports businesses saw bookings collapse at affected locations. Some community beaches were simply abandoned during the worst weeks of the inflows.

Science and Causes

The causes of the Caribbean sargassum bloom are the subject of ongoing scientific debate. The most widely accepted explanation points to a combination of factors: rising sea surface temperatures in the equatorial Atlantic, increased nutrient runoff from the Amazon and Congo river systems driven by agricultural expansion and deforestation, and changing wind and current patterns. These drivers are largely exogenous to Jamaica and other Caribbean states — they cannot be addressed by regional action alone. The Caribbean Community has discussed sargassum at several heads-of-government meetings since 2019, but the structural solutions require global-scale emissions reductions and upstream agricultural policy changes in Brazil and West Africa that are entirely outside Caribbean control.

What Caribbean governments and private actors can do is manage the arrival of sargassum on their coastlines more effectively, and explore whether the algae can be converted from an economic liability into a commercial asset. Jamaican researchers have been investigating processing sargassum into fertiliser, biofuel, animal feed, and construction materials. Pilot projects exist. None has reached commercial scale. The volumes involved in a year like 2025 are enormous — removing and processing the sargassum from a kilometre of heavily affected coastline in a single week requires industrial-scale logistics that Jamaica’s coastal management infrastructure is not currently designed to provide.

The 2025 sargassum season did not destroy Jamaica’s tourism industry. Stop-over arrivals remained broadly stable, partly because the north coast resort corridor — the principal destination for most international tourists — managed the impacts more effectively than exposed community beaches. But the season demonstrated, with unusual force, the extent to which Jamaica’s coastal economy depends on beach conditions that are now subject to increasingly severe and unpredictable natural disruption. For the tourism sector, as for Jamaica’s coastal communities more broadly, the question is not whether sargassum will return — it will — but how prepared the island will be when it does.

Related: Property Market Analysis | Latest Jamaica News

Follow Jamaica Homes on Youtube @jamaicahomes and Instagram @jamaica_homes and on Facebook @jamaicahomesnews Send us a message or email us at onlinefeedback@jamaica-homes.com or editor@jamaica-homes.com