Authorities throughout the Caribbean are releasing emergency funds to clean up huge masses of pungent, decaying seaweed. The odor from the piles of the rotting seaweed is so strong that tourists have cancelled beach holidays. Lawmakers in Tobago have deemed it a natural disaster.
Beaches in the Dominican Republic, to the north, to Barbados in the east, to the Mexican coast in the west, are beset with mounds of stinking seaweed as high as 10 feet in places. The ongoing cleanup effort is being swamped with the ongoing influx of the sargassum seaweed, choking coves, and stranding boats.
The Algal blooms are a common sight in the Caribbean but researchers say that the algae has exploded in extent and frequency in recent years. So much so that economists fear for the stability of the globe’s most tourism-dependent nations.
The picturesque turquoise waters have been fouled by the floating mats of seaweed that attract biting sand fleas and carry a stench like rotten eggs. With the start of the regions tourism season closing in, officials are calling for an emergency meeting of the 15-nation Caribbean Community.
“This has been the worst year we’ve seen. We need to have a regional effort because this unsightly seaweed could end up affecting the image of the Caribbean,” said Christopher James, chairman of the Tobago Hotel and Tourism Association.
Scientists have several ideas about what is causing the sargassum boom which started in 2011. Warming ocean temperatures and changes in the ocean currents are part of the cause. Some researchers believe that it is primarily due to land based nutrients and pollutants washing into the water, including nitrogen rich fertilizers and sewage waste.
Whatever the reason, the massive flow has become a major problem. In large concentration, the algae harms coastal environment and endangers sea turtle hatchlings when they wriggle out onto the sand where their eggs are buried. The clean-up effort may also worsen beach erosion.
“We have heard reports of recently hatched sea turtles getting caught up in the seaweed. If removal of seaweed involves large machinery, that will also impact the beaches and the ecosystems,” said Faith Bulger, program officer at the Sargasso Sea Commission.
Brian Lapointe, an expert at the Florida Atlantic University says that while the sargassum washing up in normal amounts has long been good for the Caribbean, severe influxes like those seen lately, are harmful algal blooms that can wipe out fish populations, foul the beach, harm tourism revenues and even cause coastal dead zones.
“Considering that this has been happening since 2011, this could be the new normal. Time will tell,” Lapointe said.
The drifting mats of stinking seaweed covered with berry sacs, have become so numerous that they have drifted as far as Sierra Leone and Ghana.
Sargassum, which gets its name from the Portuguese word for grape, is a floating brownish algae that generally blooms in the Sargasso Sea. The two million square mile body of warm water in the North Atlantic, is a major habitat and nursery for numerous marine species. Like coral reefs, the algae mats are critical habitats and mahi-mahi, tuna, billfish, eels, shrimp, crabs, and seas turtles all use the algae to spawn, feed or hide from predators.
But some scientists believe that the sargassum besieging a growing number of beaches, may actually be due to a high flow of nutrients from South America’s Amazon and Orinoco rivers mixing with warmer ocean temperatures.
“We think this is an ongoing equatorial regional event and our research has found no direct connection with the Sargasso Sea,” said Jim Franks, senior research scientist at the University of Southern Mississippi.
Mexican authorities will spend about US$9.1 million and hire 4,600 workers to clean up seaweed mounds accumulating along that country’s Caribbean coast. Part of the money will be used to determine whether the sargassum can be collected at sea before it reaches shore.