The harvest of softshell clams and most other shellfish is banned between Stockton Springs and the Canadian border because of high levels of a natural marine biotoxin in the water that can cause amnesic shellfish poisoning. ELLSWORTH AMERICAN PHOTO BY JACQUELINE WEAVER

Shellfish closure expanded; cost to industry mounts

ELLSWORTH — Downeast shellfish harvesters are reeling as the Department of Marine Resources last Friday expanded its closure of the Downeast clam and mussel fisheries because of the westward spread of the microscopic marine organism that causes amnesic shellfish poisoning (ASP).

On Sept. 27, DMR closed Cobscook Bay from Perry and Lubec to the Canadian border to the harvesting of mussels. A day later, the department expanded the closure to include clams.

On Sept. 30, DMR closed the entire state east of Otter Point on Mount Desert Island to all clam and mussel harvesting. Last week, the closure boundary was shifted westward to encompass much of Penobscot and Blue Hill bays and the outer islands.

“Currently, mussels, carnivorous snails and surf clams are closed from Deer Isle to the Canadian border,” DMR spokesman Jeff Nichols said in an email on Friday. “All other clams (softshell and hardshell) are closed from Isle au Haut to the Canadian border; European oysters are closed from Deer Isle to Machiasport.”

Harvesters and dealers have already felt the impact.

On Sept. 30, DMR ordered the recall of mussels and mahogany quahogs harvested or wet stored in the Jonesport area between Sept. 25 and Sept. 30. It also ordered a recall of clams harvested in the area between Cranberry Point in Corea and Cow Point in Roque Bluffs between Sept. 28 and Sept. 30.

According to Nichols, the recall affected five licensed shellfish dealers, “and more than 10,000 pounds of product was recovered and destroyed, which was more than 96 percent of the total product recalled.”

Maine Shellfish Co. in Ellsworth was one of the dealers affected by the DMR order.

“We didn’t have to do a recall, but we destroyed a quantity of shucked clams and clams in the shell,” James Markos, general manager at Maine Shellfish, said Monday. He estimated the company’s cost at “a couple of thousand dollars.”

The good news, Markos said, was that the closure comes at a time when there are “enough clams to take care of marketplace demand” which, he said, “really tails off” in the fall. At the peak of the season — during the summer — “the impact would have been huge.”

For the clam diggers who work around Pembroke, the impact is already huge.

Tim Sheehan runs Gulf of Maine Inc. in Pembroke and, at this time of year, buys clams from as many as 30 diggers daily. As of Tuesday, he said, Cobscook Bay will have been closed to harvesting for two weeks and “these guys are starving down here. It’s very bleak.”

Sheehan started buying clams five years ago from about a dozen diggers. Now “a couple of hundred” harvesters sell to his shop.

According to Sheehan, his company was paying out $3,000 to $5,000 per day to local diggers before the shutdown. By his estimate, harvesters are losing a minimum of $100 per tide if they aren’t allowed to dig for clams. One his regular diggers recently told him that he may have to seek general assistance from the town if the shutdown continues.

“I’m worried about the winter,” Sheehan said. “People need to buy their oil for the winter. It’s kind of scary.”

So is the threat posed by amnesic shellfish poisoning.

According to the Woods Hole Oceanographic Institution, amnesic shellfish poisoning is caused by consumption of shellfish containing domoic acid, a biotoxin produced by tiny organisms known as Pseudo-nitzschia.

ASP “can be a life-threatening syndrome that is characterized by both gastrointestinal and neurological disorders.” According to WHOI, gastroenteritis usually develops within 24 hours after consumption of toxic shellfish. Symptoms can include nausea, vomiting, abdominal cramps, and diarrhea. Neurological symptoms can appear, usually within 48 hours of toxic shellfish consumption, including “dizziness, headache, seizures, disorientation, short-term memory loss, respiratory difficulty and coma.”

In 1987, four victims died of ASP after consuming toxic mussels from Prince Edward Island, Canada.

In Maine, shellfish harvesters are used to dealing with the summer algal blooms that cause “red tide” and close fisheries because of concerns about paralytic shellfish poisoning (PSP). Autum algal blooms are much rarer.

According to DMR, low levels of the ASP-causing organisms have been present in the Gulf of Maine for many years. This is the first time, though, that regular shellfish safety testing has ever found levels high enough to warrant concerns.

On Monday, how much longer the Downeast shellfish industry would be closed remained uncertain. According to DMR, the U.S. Food and Drug Administration sets a domoic acid safety limit of 20 parts per million (ppm) in shellfish.

“Reopening criteria are two clean shellfish meat scores (less than 20 ppm of domoic acid) seven days apart.” Maximum scores in some areas were over 100 ppm early last week.

Stephen Rappaport

Stephen Rappaport

Waterfront Editor at The Ellsworth American
Stephen Rappaport has lived in Maine for nearly 30 years. A lifelong sailor, he spends as much time as possible messing about in boats. [email protected]

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