Quahogs have long been associated with money and wealth.
“Quahog” comes from an Algonquian word for hard clam, but its scientific name is Mercenaria mercenaria, from the Latin for wages.
The quahog got its scientific name when the fur trade between European colonists and Indigenous peoples was of great economic importance. Quahogs, in the form of wampum, were an important element in that trade.
The wampum was made with purple and white beads cut from seashells and woven into belts. The source of the purple beads? The purple ring that forms inside some quahog shells.
As a form of money, wampum became so important that it was used as the official currency in British and Dutch colonies as late as the 1660s, according to the McCord Stewart Museum in Montreal.
In other words, quahogs were once synonymous with money.
Quahog shells are no longer of much value, but their meat is. With the dramatic decline of soft-shell clams in Harpswell, harvesters here have become increasingly dependent on quahogs — also known as hard clams — for their livelihoods.
In 2009, soft-shell landings in Harpswell reached about 500,000 pounds, according to state records. By 2016, they had plummeted by 80% to about 100,000 pounds. The harvest has eclipsed 200,000 pounds twice since then, but in 2023, it was back down to about 134,000 — still far below 2009’s figure.
In response to the scarcity of soft-shell clams, local harvesters have shifted their efforts to quahogs. From 2011-2015, the quahog harvest in Harpswell ranged from about 5,000 to 60,000 pounds. By 2023, the quahog harvest in Harpswell had skyrocketed to 458,000 pounds.
In that period, the value of quahog landings also grew, from about $80,000 in 2015 to nearly $900,000. By contrast, the value of Harpswell’s soft-shell landings in 2023 was $384,000.
Clearly, for Harpswell’s diggers, quahogs are now where the money is.
More predators, less prey
The reason for the decline in soft-shell clams is clear, according to Brian Beal, professor of marine ecology at the University of Maine at Machias.
“There’s no mystery,” Beal said. “The whole thing comes down to green crabs and warming water.”
Since 1987, Beal has been conducting clam research all along the Maine coast. His research shows that the rapidly warming waters of the Gulf of Maine are driving an increase in invasive green crabs.
Soft-shell clams, as their name suggests, are susceptible to predation by crabs. By contrast, quahogs, as they grow, develop hard, tightly closed shells that provide an effective defense against crabs.
Factors besides green crabs may be at work, but predation is far and away the main cause, Beal believes.
“I haven’t been able to find anything except predation that’s important enough to talk about,” he said.
The main limit on green crabs is cold water temperatures in winter. Cold winters are “what we need” to reduce the population, Beal said.
What’s happening in Harpswell is a reflection of trends along the Maine coast that go back decades, according to Beal.
Soft-shell landings statewide peaked in 1977, at 38.4 million pounds. In 1991, landings had fallen to what was then a historic low, 7.24 million pounds. That record low was broken again in 2018, 2020 and 2023. The harvest of 5.2 million pounds in 2023 was less than one-seventh of its peak a half-century ago.
As in Harpswell, statewide quahog landings have risen as soft-shell stocks have waned, more than doubling from just under a million pounds in 2016 to 2.4 million in 2023.
‘They don’t call it Quahog Bay for nothing’
If Beal is correct, then the future for harvesters in a warming world lies in quahogs. And Harpswell is blessed with lots of them.
Scott Moody is a lifelong resident of Harpswell, past chair of the town’s Marine Resources Committee, and a shellfish dealer based in Cundy’s Harbor. He learned of the importance of quahogs as a child.
He recalls how much his grandparents, Wygonda and Ed Bennett, depended on quahogs for food. They would walk from their house on Cundy’s Harbor Road to gather quahogs in Quahog Bay and then lug them home, where they put them up in jars that lined the top three shelves of their basement pantry.
Most of them ended up in chowder. During the cold months, “There was always a giant pot of chowder going” for them and for anyone else who came through the door, Moody said. “They basically ate chowder all winter.”
The quahogs were abundant then and they are now. “They don’t call it Quahog Bay for nothing,” Moody said.
That abundance is serving Harpswell’s harvesters well. “They’re lucky to have it,” Moody said.
To differentiate between the two species of clams, harvesters generally refer to soft-shells simply as clams, and to hard clams as quahogs.
Two decades ago, clam harvesters could make about $250 a tide — pretty good money back then, Moody said. Today, quahog harvesters can bring in 1,000 to 2,000 quahogs per tide, which works out to about $300 to $600, he said.
Many clammers prefer digging quahogs to clams, because they are found closer to the surface of the mud. “It’s an easier dig,” Moody said.
Growing the resource
David Wilson, the current chair of the town’s Marine Resources Committee, harvests both clams and quahogs. He laments the demise of clams. Back in the day, there were perhaps 16-18 harvesters relying on clams. He estimates that there are about a dozen harvesters working regularly now, all focused on quahogs.
“If I go digging, that’s what I dig,” he said. “Considering the effort, I’d rather dig quahogs.”
The market favors littlenecks, the smallest quahogs that can be legally harvested. In mid-January, harvesters were getting 30 cents per littleneck, according to Wilson. Larger sizes were fetching considerably less: 20 cents.
He said he is able to bring in 1,500 to 2,000 quahogs per tide. His income from digging these days is not quite what it once was.
“I made a little more digging clams,” he said. Still, “it’s pretty good money for the time actually harvesting,” he added.
While the digging may be reasonably good now, Wilson and other harvesters are working with the town to ensure the quahog harvest remains sustainable.
The town ran a clam flat seeding program from 2020 through 2023, according to Harbor Master Paul Plummer. Using floating grow cages, tiny seed clams were grown bigger to make them less vulnerable to predators.
Only when quahogs reach about an inch or so in length do their shells become strong enough to protect them from predators such as green crabs, according to Beal, the researcher at the University of Maine at Machias.
So far the town has not been able to produce quahogs that big. The municipal program has successfully grown quahogs up to about 6 millimeters in length, or about a quarter of an inch.
In the fall, Harpswell’s harvesters, doing the conservation work required to maintain their commercial licenses, transfer the small quahogs to clam flats. Areas that have been seeded include Card Cove, Diamond Cove, High Head, Long Reach, and Ridley Cove, Plummer said.
No seeding of flats occurred in 2024, but Wilson hopes the effort will resume in 2025. He has been pleased with the survival rate of the quahogs in the reseeded flats.
The town’s program is not the only attempt underway in Harpswell to boost the quahog population. Wilson has embarked on a private aquaculture project that includes two 4-acre plots in Long Reach and Middle Bay. At the heart of this endeavor are two upwellers that he built with the help of family members.
From a distance, the upwellers look like the floats lobstermen use to store their traps. But these structures house chambers called silos where the small bivalves are raised.
The bottom of the silos are covered with mesh. A pumping system draws seawater up through the mesh into the silos, bringing oxygen and nutrients to the young mollusks.
Because the upwellers are more efficient than the growing cages used by the town, Wilson has been able to grow quahogs to about 12 millimeters, or about a half-inch.
Quahogs can be harvested when they reach 1 inch at the hinge. A quahog of this size, called a littleneck, would be about 2 inches at its longest dimension.
Wilson started his aquaculture operation four years ago and expects to harvest his first quahogs this spring. However, he does not expect — nor does he want — aquaculture to supplant the harvesting of wild quahogs.
He hopes that the young clams planted under the municipal program will serve as additional breeders, boosting the wild population in coves across town.
While aquaculture may have its place, Wilson is putting his faith in a sustainable wild population that will thrive in a warming climate. He doesn’t believe scattered aquaculture farms will ever produce on the scale of the many coves indenting Harpswell’s extensive coastline.
Given the extent of the clam flats here, “There’s no way you can compare an aquaculture farm to the town of Harpswell, no way,” he said.
