Stinky seaweed besieges beaches

Mats of smelly seaweed were washed up on area beaches for the Fourth of July.

Wind, tide and current are pushing clumps of the stuff ashore. It's a species of brown algae found along the Atlantic coast called sargassum, experts said.

Persistent onshore winds probably played a role in the arrival of the brownish weed, which provides a habitat for sea life, said Dr. Lou Burnett, director of the Grice Marine Lab at the College of Charleston.

"It'll just sit there and rot away," Burnett said.

The sargassum weed appears in huge floating masses in the Sargasso Sea of the north central Atlantic. It likely makes its way ashore from the Gulf Stream some 40 miles to 60 miles offshore, experts said.

"This year has really been kind of heavy," said Folly Beach Mayor Carl Beckmann.

He noted that sargassum provides habitat for turtle hatchlings. What's not washed back to sea by the tide catches the sand, which helps slow beach erosion, he said.

Sullivan's Island Town Manager Andy Benke said the weed poses no hazard or danger to beachgoers. "It's on the beach at Sullivan's Island and Isle of Palms," Benke said.

It's hard to say whether there is more sargassum on the beach than usual.

"I don't think the town has ever monitored it. It's just one of those natural occurrences," Benke said.

Isle of Palms City Administrator Linda Lovvorn Tucker said the island has lots of marsh reeds washed ashore on the beaches. "We have some of it (sargassum), but not an alarming amount," she said.

Sargassum has numerous small round spheres that are floats filled with carbon dioxide. They provide buoyancy to the algae. At sea, lines of sargassum can stretch for miles along the surface. The clumps of floating brown algae often are concentrated by the strong winds and wave action associated with the Gulf Stream, according to the National Oceanic and Atmospheric Administration.

Young fish species, shrimp and crab hide from predators and feed in sargassum. Many of them are camouflaged to match the algae. Small dolphin fish live very close to sargassum, and as they become larger, they patrol in schools underneath the weed lines. Fishermen often look for the weed lines to improve their chances of catching dolphin fish. Amber- jacks (among other jacks), filefish and trigger fish are dominant groups in sargassum, according to a NOAA Web site.

Reach Prentiss Findlay at 937-5711 or pfindlay@postandcourier.com