Algae bloom in the southern tip of Florida threate

It seams that every week I am finding these articles !!!!!!!!!!!!!!!!!

Algae bloom in the southern tip of Florida threatens sea life

By David Fleshler
South Florida Sun-Sentinel
Posted August 11 2006

 
An enormous bloom of blue-green algae has spread across the bays of the southern tip of Florida, threatening coral reefs and seagrass beds, in an event that state scientists say appears to be partly the result of the controversial widening of the main road into the Keys.

The algae bloom has reached the waters of both Everglades and Biscayne national parks, where scientists are working to assess the damage.

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"We are very concerned about it for water quality and the health of the bay," said Elsa Alvear, chief of resource management at Biscayne. "Seagrasses, like coral, are extremely important to marine ecology and very important to the productivity of the bay."

Among the most ancient forms of life, blue-green algae are bacteria that live in water and obtain nutrition through photosynthesis. Although they are not toxic, like the algae that cause red tides, they can develop in dense concentrations that block sunlight from seagrass, coral and other undersea organisms.

Seagrass, which would die without enough light, is an important part of the marine ecosystem, providing shelter for juvenile fish and food for manatees, sea turtles and other creatures.

A July 28 report by the South Florida Water Management District said the "highly unusual" algae bloom appeared over the past few months and seemed to increase in July. The report says the bloom was probably caused by an increase in the concentrations of phosphorus, a nutrient used by plants and bacteria. The hurricanes of 2005 probably caused the initial rise in phosphorus by sweeping it off the land and into the water.

But the report says the road construction, which involved mulching mangroves and tilling soil, contributed phosphorus to the water that was also a likely cause of the bloom. The report noted that the algae bloom was found on both sides of U.S. 1 into the Keys, where the work was being done and where there was no previous record of algae blooms.

Capt. Lain Goodwin, who runs a charter-fishing business out of Blackwater Sound off Key Largo, said the water was "completely green."

"You can't see your hand in the water," he said. "It has decimated my fishing in these areas. Last year, I was catching permit, grouper, snapper and triggerfish. And this year, it's been devoid of all that."

"I know that it started right around the road construction," Goodwin said.

The $270 million road project calls for expanding the 18-mile, two-lane stretch of U.S. 1 from Florida City to Key Largo by widening the pavement from 32 to 54 feet, installing a median between opposing lanes and replacing two bridges. The work was intended to hasten hurricane evacuations and reduce accidents on the notoriously dangerous stretch of road.

The Sierra Club, Friends of the Everglades and the Florida Keys Citizens Coalition unsuccessfully fought the project in court, contending it did not meet state and federal environmental standards. The groups said alternatives weren't adequately studied.

Audubon of Florida called on the water management district, which had issued a permit for the road project, to limit or halt the work. Peter Frezza, an Audubon scientist, said it was far more likely that the roadwork, not the hurricanes, was the major cause of the algae. He noted that high concentrations of algae existed on both sides of the road and that phosphorus levels remain high a year after the storms. He said the bloom had already started to kill seagrass.

"All of Florida Bay is so productive because of the seagrass we have," he said. "Without the seagrass, we would have nothing. It would be a dead bay."

Chip Merriam, the water management district's deputy executive director, said the district was trying to assess the causes of the bloom and what could be done to prevent the road work from adding to it. He said the Florida Department of Transportation, which is doing the work, was being extremely cooperative, installing screens and taking other steps to reverse any contributions to the source of the algae bloom.

He said it still wasn't clear whether the road work played a major role in the algae bloom or whether the bloom resulted mainly from the hurricanes.

"It's still not conclusive," he said. "A lot of things happened this year."

Barbara Culhane, environmental project manager for the transportation department, said her agency was working with water managers on additional tests to eliminate the work as a source of the bloom.

"We're still gathering information, but we don't believe there is any direct correlation," she said.

The road project also received a permit from the Army Corps of Engineers.

John Studt, the Corps' South Florida permits chief, said the Corps learned of the algae this week and was looking into it.

"In our permit evaluation, which was extensive, I don't recall this particular issue being raised, although it may have been," he said.

Staff writer Michael Turnbell contributed to this article.

David Fleshler can be reached at [email protected] or 954-356-4535.

Rick