OLD ORCHARD BEACH, Maine — Following Monday’s announcement that a large portion of the Maine coastline was declared off-limits to clam harvesting due to red tide, the waters, shorelines and flats in the Old Orchard Beach area have again been declared safe for harvesting by marine officials.
The Maine Department of Marine Resources and its Bureau of Public Health announced Thursday it had partially repealed a ban enacted Monday on clam harvesting in the waters off Old Orchard Beach up through the coast to Harpswell, rescinding a previous order making it unlawful to harvest clams in the affected waters.
On Monday, the department closed the area between OOB and Harpswell to clam digging due to the risk of paralytic shellfish poisoning caused by the red tide.
At the time, areas north and east of Camp Ellis, toward OOB, were closed to clam digging. They were declared safe on Thursday, although harvesting bans are still in place for areas north of OOB.
Also remaining are bans on harvesting mussels, European oysters and carnivorous snails along the Maine coastline due to the biotoxins caused by red tide.
Red tide is caused by algal blooms that release toxic phytoplankton into the water. If the algal bloom is large enough, it can sometimes turn coastal waters a red color, although J. Kohl Kanwit, director of the Maine DMR’s Bureau of Public Health, said this is not always the case.
“You cannot see the phytoplankton that causes ‘red tide’ in the water,” he said in an email Friday.
The algal bloom can deplete oxygen waters and release toxins that can be harmful to humans or other animals. These kinds of toxins build up specifically in shellfish, and can cause health problems if contaminated shellfish are consumed.
Among them is paralytic shellfish poisoning, which can disrupt nerve function and may result in death if not treated.
Other threats include the less-severe, but definitely-annoying, diarrhetic shellfish poisoning that can cause diarrhea, nausea, vomiting, abdominal pain and cramps.
Causes of red tide include warming oceans and rain followed by sunny days, as has been the case the past few weeks. Kanwit said he expects additional bands to be enacted as the summer season ensues.
While red tides can be a public health concern, they’re natural, and often misunderstood, said Craig Pendleton, a former commercial fisherman who now heads the Biddeford + Saco Chamber of Commerce + Industry.
“It’s a perception issue. When you hear that any type of seafood that has been given a government ban, you always think the worst,” Pendleton said Friday. “Red tide only affects mollusks, so anything that filter feeds.”
Kanwit said the same.
“Red tide closures only impact bivalve shellfish which are filter feeders and therefore bioaccumulate phytoplankton,” he said. “Other seafood is perfectly safe to eat.”
“But people get this general perception it’s all bad,” Pendleton said.
In addition to putting clam diggers temporarily out of business, that perception causes consumers to abstain from eating seafood in general, which Pendleton said puts a significant dent in one of Maine’s largest — and most renowned — industries.
“It ripples through the economy until people realize it’s just (about) clams,” he said.
The DMR doesn’t keep track of the number of clam diggers in the state or in York County who might be affected by the red tide bans, Kanwit said. Pendleton said there may only be about a dozen who typically dig in the areas off Old Orchard Beach toward Pine Point in Scarborough.
Kanwit said as long as people buy their shellfish from reputable dealers, there is no risk to public health.
“(People) should only buy from certified shellfish dealers who follow strict shellfish sanitation standards, are aware of the current closures, the species and areas impacted and are regularly inspected,” he said.