NewsPress.com

September 3, 2007

Research may help fight red tide

http://www.news-press.com/apps/pbcs.dll/article?AID=/20070831/NEWS0105/708310380/1075

by Rob Waters and Jacob Ogles

Researchers are a step closer to understanding what causes red tide, a phenomenon which has affected Southwest Florida’s beaches frequently for more than three years.

More than 20 years ago, a scientist at Columbia University in New York suggested a certain chemical reaction might allow algae to produce the deadly material.

The theory was unproved until recently when chemists at the Massachusetts Institute of Technology say they became the first to create such a reaction. The advance may someday help scientists intervene with nature and prevent the poisonings, which have caused millions of dollars in losses to the seafood industry, researchers said.

“Red tides happen in coastal environments all around the world, with one to five notable outbreaks a year,” said Tim Jamison, the MIT chemist who led the research, said in a telephone interview. “They can kill a lot of shellfish, and it can look pretty frightening, like someone dropped a bomb into the ocean and they were killed by shock.”

Lee County’s artificial reefs experienced a series of fish kills in 2004 which were attributed to red tides along Southwest Florida’s coasts. The problem worsened in summer 2005, when red tides produced a no-oxygen dead zone that caused die-offs of fish, crustaceans and mollusks from Pasco to Lee County. In 2006, Lee County natural resources scientists said Mary’s Reef, normally home to more than 20 fish species, had just three there last year.

“All of the coastal communities here depend on tourism, so it definitely has a big effect here,” said Bonita Springs Mayor Jay Arend.

This year, scientists say water quality has returned and species have come back.

Red tide can cause eye and throat irritation in people nearby. Oysters and other shellfish exposed to red tides shouldn’t be eaten, as they can make people seriously ill with neurotoxic shellfish poisoning. Fish, crabs and shrimp don’t absorb the toxins from the algae, though people shouldn’t eat fish found sick or dead.

The toxins in red tide kill fish by paralyzing their nervous systems so they can’t breathe, and during a red tide, dead fish often wash up on shore.

“There have been so many theories about what causes it to happen,” said Lee County Commissioner Bob Janes. “That is why this research is so critical.

“If we are ever going to have an impact on red tide, we need to know how it originates, how it grows, how it develops and what encourages it to expand.”

That has caused temporary beach closures all along Lee County’s shores numerous times since 2004.

“Just a few weeks ago we had a great amount of red algae wash up on the beach and had to be cleaned up,” Arend said. “It is not attractive. And though it wasn’t as bad this time as it has been, it can cause a lot of problems for people with respiratory issues so they can’t even go to the beach.”

As scientists develop a better understanding of red tide, Arend said, government officials can learn how better to mitigate the effects. He is convinced nutrient releases from the Caloosahatchee River into the Gulf of Mexico helped feed the problems here in recent years and thinks controlling discharge has helped curb the issue.