ELLSWORTH – The 2005 season is generally considered among the worst for red tide closures, but officials with the Maine Department of Marine Resources fear this season could be even worse.

“This is the largest closure for clams that we have ever had to put in place in eastern Maine, including many areas that have never been closed for red tide before,” Darcie Couture, director of biotoxin monitoring for DMR, said in an e-mail sent late last week.

Red tide is caused by blooms of naturally occurring algae that produce a toxin that then is absorbed by shellfish as they feed. Eating shellfish affected by the toxins can cause sickness or death in humans. It is always present to some degree off the Atlantic coast and it almost always results in closure of certain areas to shellfish harvesting. The state maintains an aggressive monitoring and testing program to ensure that areas are closed before red tide reaches dangerous levels.

Those closures have increased steadily in recent days, particular in waters off Hancock and Washington counties.

“Basically, there is a red tide closure in place for mussels from Isle au Haut to the Canadian border, with a few exception areas,” Couture wrote. “There is a red tide closure in place for clams from Moose Neck [in Addison] to the Canadian border, with a few exception areas in Machias and the Cobscook Bay area.”

The 2005 season was a record-breaker for red tide, at least from an economic standpoint. According to Kevin Athearn, assistant professor of natural resource economics at the University of Maine at Machias, the coastal fishing economy lost nearly $5 million in sales that year. Athearn also said wholesale dealers and businesses linked to the shellfish industry incurred additional losses indirectly, as much as $12 million.

For every intertidal acre of suitable clam habitat closed, Athearn estimated, gross sales lost range anywhere from $288 to $14,400.

How this year’s closures will affect the industry remains to be seen.

Becky Beal, vice president of Beals Lobster Co. Inc. in Washington County, is one of many in the Down East fishing industry who hopes the recent closures don’t last long.

“We have been able to fish in other areas, but we don’t know if they will yield any catch,” she said last week. “We’re hopeful.”

Pete Daley, owner of Eastern Maine Mussel in Hancock, said red tide has limited his harvest, “but we have a large area that we buy from, so we’re still able to process,” he said. “Sometimes, though, you just have to wait it out. The year before last, we lost three weeks in a row, which is difficult when you have eight or 10 employees who want to work.”

DMR has a much better monitoring program than it did in 2005, thanks in part to a $143,000 federal disaster grant which allows DMR to keep some individual areas open that might otherwise have been closed. No one has ever been sickened by shellfish collected in areas deemed safe by the state.

Ross Chipman at Atlantic Shellfish in Jonesport said his company is diversified and doesn’t rely solely on clams or mussels, but he admitted things have been slow for a couple weeks.

“We hope it’s only temporary,” he said. “But even with the testing, they have to have two weeks of clean tests.”

Daley said his company uses four to six harvesters that reach from Stonington to the Canadian border. In most years, if there are red tide closures in some areas, he can rely on catches from unaffected areas, but that has been a little harder this year.

“You try to keep your inventory up and rotate property to account for any foreseeable closures because you never know,” he said.

Couture indicated she didn’t expect any changes to any of the closures until early this week.

Andrew Thomas, professor of oceanography at the University of Maine’s School of Marine Sciences, said scientists have a better understanding of when and why blooms occur in midcoast Maine and to the south.

Toxic blooms of red tide are more likely to happen in the southern areas when strong northeasterly winds early in the season blow water – and therefore red tide algae – toward the coast.

But the currents and water conditions along Maine’s eastern coast and northward into Canada are different. In those areas, northeasterly winds are less of a factor in causing blooms, Thomas said during a recent interview.

That could help explain why conditions are improving to the south but worsening Down East, Thomas said. But the factors that cause a bloom in Down East waters need more research, he said.

“They really do appear to behave on their own,” Thomas said of the distinct regions. “We’ve had years when the whole coast was bad. But then again, I can point to years when it was bad Down East” and southern coastal areas were fine.

People such as Beal don’t like the idea of hanging their hopes on the weather.

“The state does what it can in terms of testing and providing us alternative areas,” she said, “but we’re still up in the air.”

BDN writer Kevin Miller contributed to this report.

erussell@bangordailynews.net

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