Shellfish limits mount as red tide outbreak creeps north Prices spike, but market supplies safe for consumers, Maine officials say

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The remaining clams and mussels that are safe to eat are increasing in price, and customer demand for steamers is plummeting, in response to one of the worst red tide seasons in decades.

The toxic plankton, which can make shellfish deadly, is lingering in coves from Penobscot Bay to Cape Cod, with no signs of abating.

“It’s not ‘here today, gone tomorrow,'” said Maine Department of Marine Resources scientist Jay McGowan, who is monitoring the outbreak.

Earlier this week, the DMR shut down mussel, oyster and clam fishing along miles of Maine coastline where “significant” blooms of red tide have been found.

Meanwhile, Massachusetts Gov. Mitt Romney on Thursday declared a state of emergency, estimating losses at $3 million per week.

Red tide is a natural phenomenon, so old that some say it was to blame for the “sea turned to blood” of biblical fame.

Every summer, currents carry toxic plankton from deep water toward the New England coast. At low levels, the microscopic organism known as Alexandrium fundyense is harmless and invisible.

But when it builds up to densities that turn the water a deep reddish-orange, hence the moniker “red tide,” it can be deadly.

In recent months, the concentration of plankton in the Gulf of Maine has been higher than in any year since the early 1970s, biologists said. The Woods Hole Oceanographic Institute, which is studying the outbreak, describes the situation as a “perfect storm.”

The winds from recent rainstorms carried the plankton unusually close to shore, where it has thrived in the warm, nutrient rich water and stymied the shellfish industry.

Filter-feeders like clams, oysters and particularly mussels take the red tide plankton into their bodies. While it doesn’t hurt the shellfish, the people and wildlife who eat an Alexandrium-saturated clam can experience numbness, tingling, nausea and vomiting.

And if the concentrations are high enough, a person who ate a tainted mussel could die from paralytic shellfish poisoning, or PSP, in which the toxin causes suffocation.

No one has died of PSP in Maine since the state started monitoring red tide blooms 50 years ago, McGowan said.

Shrimp, lobster and crabs do not filter-feed and are not affected by red tides. And once the red tide moves on, shellfish can flush the toxins from their systems so that they are safe to eat. But it takes weeks for the shellfish to recover, McGowan said.

On Thursday, McGowan left his lab in Lamoine to sample shellfish in Hancock and Washington counties, just beyond the northeastern boundary of the outbreak, to test them for Alexandrium.

If he finds dangerous levels of the toxin, an emergency shellfish closure order could be issued in a matter of hours – and that’s a distinct possibility over the next few weeks, he said.

The outbreak line stops somewhere in the Schoodic Peninsula area for now, but red tide is steadily creeping north along the coast. Clams in Winter Harbor were fine last week; now they’re unsafe.

And recent tests show that mussels in the same area contain 10 times more toxin than they did a week ago, McGowan said.

“I have no idea how long and how hard it could be,” he said.

Scientists at Woods Hole are predicting perhaps three more weeks before the Alexandrium dies out, taking the outbreak well into the July Fourth peak shellfish season.

If this keeps up, it could be a tough summer, said Kip Crute, who has run a seafood market in Cushing since 1969. Clams from safe areas have doubled in price since last year, due to the red tide outbreak and rain closures (in response to pollution runoff from heavy storms).

But that’s not what’s keeping customers away, Crute said. For Maine’s nearly 2,000 clam diggers and the dealers who sell their catch, public fear of red tide that keeps sales low can be as harmful as the outbreak itself.

The soft-shell clam business alone pumped $15.86 million into the state’s economy in 2003, according to DMR statistics.

Just across the St. George River, in Tenants Harbor, Great Eastern Mussel Farms is struggling to convince people its product is safe.

Demand hasn’t yet slipped, but just this week, a supermarket manager in Boston called the company, asking for information to help reassure its customers that all mussels aren’t deadly, quality control manager Dave Preston said Thursday.

Both businesses said they have responded to the outbreak by buying or harvesting from Cobscook Bay, and other areas north and east of the areas affected by red tide.

The Department of Marine Resources isn’t letting anything that’s been near red tide on the market, they said.

“If you see it at the seafood counter, it’s safe,” Preston said.

The Associated Press contributed to this story.