N.Y. scientists try to understand brown tide Algae outbreaks have cost Long Island $100 million in 12 years


HAMPTON BAYS, N.Y. - In 1985, microscopic brown algae overwhelmed the Peconic Estuary at the eastern tip of Long Island. The phenomenon became known as brown tide because it turned the water a murky brown. It also scared away tourists and killed off shellfish.

More than a decade later, the cause of brown tide remains a mystery.

"But there is new hope that we may soon be able to find some of the answers," said Suffolk County Executive Robert Gaffney, as he welcomed the recent launching here at Meschutt County Park of three buoys designed by scientists at Brookhaven National Laboratory to understand the reason for the algal blooms.

In the last 12 years, brown tides have wiped out seven annual shellfish crops valued at $3 million a season and have cost the tourist industry on eastern Long Island more than $100 million, Gaffney said.

Creighton Wirick, an oceanographer with Brookhaven Laboratory who heads the project, said the meter-long buoys were equipped with detectors called fluorometers that measure the amount of chlorophyll in the water as a way of calculating the concentration of brown tide algae in the water.

Other detectors on the buoys will record the temperature of the water, its salinity and its amount of dissolved oxygen. The instruments are attached to a radio transmitter that will beam the data to a computer at the laboratory every 15 minutes.

"Within 20 seconds of its arrival, the data will be available over the Internet to scientists around the world who might be working on similar projects," Wirick said.

With the brown tide season fast approaching, some blooms have already been detected in Flanders Bay at the western end of the Peconic Estuary, where one of three buoys was placed. A second buoy was anchored west of Robins Island in Great Peconic Bay. The third was positioned in West Neck Harbor off Shelter Island.

"It's too early to tell whether there will be a damaging bloom this summer," Wirick said. "We've had two good years in a row, and if this is a good one, we should have a great crop of scallops."

Wirick said he hoped the data would help prove a theory held by many Brookhaven scientists that the brown tide was caused by alternate rainy and dry years and the presence of large amounts of nitrogen in ground-water runoff.

"Our hypothesis is that while there is a normal green algae in Peconic Bay, there is also always some of these brown algae around," he said.

"In certain dry years, the brown tide excels and beats out the normal green tide," he said. "And since this has been a wet year so far, the forecast for this summer is a good one."

John Marburgher, the director of Brookhaven National Laboratory, said: "The reasons why this phenomenon occurs still remain cloudy. We hope the buoys will add a few more pieces to the puzzle."

Pub date: 6/14/98

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