Thursday, February 22, 2018

Beach seaweed problem coming from far away


plentiful: Seaweed has fouled the beaches along Trinidad’s east coast, the result of a natural phenomenon taking place thousands of miles away in the Sargasso Sea, in the North Atlantic. —Photo: Richard Charan

Mark Fraser

THE seaweed coming ashore on beaches along Trinidad’s east coast and Tobago is the result of a natural phenomenon happening thousands of kilometres away in the North Atlantic Ocean.

For the past three weeks, bathers have found the shoreline between Manzanilla and Guayguayare covered in a think mat of seaweed, which had made it impossible to go swimming, and which has also fouled the nets of fishing boats.

The beaches along the east coast were all but deserted last weekend.

Institute of Marine Affairs (IMA) acting director, Dr Donna-May Sakura-Lemessy, said the seaweed  was a brown macroalgae known as Sargassum, originating in the Sargasso Sea.

The Sargasso Sea is located  in the middle of the Northern Atlantic Ocean. 

Sakura-Lemessy said during this time of year, strong prevailing winds, storm activity and spiralling currents disperse the weed throughout the region. 

As currents intersect with the edges of the Sargasso Sea, they break off parts of the larger Sargassum mat that covers more than three million square kilometres, she said.

Sakura-Lemessy said: “The currents carry the seaweed along with them, eventually sweeping it eastwards into the Caribbean islands where local currents carry it ashore.  

“This is a natural phenomenon that occurs cyclically, but some years are worst than other. In 2011, the same phenomenon was experienced.  Unfortunately, once ashore Sargassum is slow to decompose resulting in foul smells and it is aesthetically unpleasant to beach goers.”

She said: “There isn’t much use for the Sargassum as it does not make for an economically feasible fertiliser. Most countries hire teams or volunteers get together and rake up the seaweed.  Some hotels in Tobago, for example Bluewaters Inn, hire a backhoe on mornings, which rakes the seaweed and buries it beneath the sand.”

Lemessy said it was not hazardous.

Minister of the Environment and Water Resources Ganga Singh said he was unaware of the seaweed along the coast but would liaise with IMA and the Environmental Management Authority (EMA) to find out more.     —Sue-Ann Wayow