On the resort beaches of the Yucatan Peninsula masses of stinking sargassum seaweed have been washing ashore for several years. From Miami Beach to Barbados sargassum is spreading across the Caribbean and Florida. The seaweed is killing fish, turtles and other sea life as well as befouling beaches and damaging fisherman’s nets. 

The Washington Post reports: 
Scientists warn that the algae known as sargassum are a grave new threat to the Caribbean — one as potentially life-altering as rising sea levels or destructive hurricanes.

The algae support birds and sea life in the open ocean but wreak environmental havoc near the shore. As they start to decay, they emit hydrogen sulfide fumes that can kill fish, coral and sea grass and cause headaches and nausea in people. When piled high, the weed blocks endangered sea turtles from laying their eggs on shore and prevents their spawn from migrating to the ocean.

Barbados declared a national emergency in June and has deployed soldiers to try to clear beaches of the weed. In Antigua, the luxury resort St. James’s Club has been forced to close temporarily after its bay was overtaken by a rust-colored layer of seaweed the size of several football fields. In Trinidad and Tobago, officials are calling for the development of an early-warning system that would use satellite imagery to predict the severity of “sargassum season” during late spring and summer….

Now climate change and ocean pollution appear to be fueling new sargassum blooms.

Many scientists believe that a combination of warmer water and a fertile mixture of sewage, agricultural fertilizers and other river runoff may have created the perfect conditions for algae growth — and led to the formation of a second sargassum-filled sea off the coast of Brazil. They believe that much of the seaweed invading the Caribbean may come from this second patch.

“There’s a sense that this is another man-made natural disaster,” said Hazel Oxenford, a Barbados-based biologist at the University of the West Indies.

In Florida, sargassum is only one of three very different types of algae wrecking havoc to the environment and tourism.  A massive red tide algal bloom, fueled by pollution and climate change, is spreading up the state’s west coast killing thousands of tons of sea life in its wake.

South Florida is also suffering from a highly toxic blue-green algae bloom spreading stinking green slime from rivers to the coast. Agriculture runoff from the Florida sugar industry is thought to have accelerated the outbreak.