Maine sea farmers are taking a page from Japan (again), an industry titan, to test a new method of farming scallops they hope will grow larger mollusks, and grow them faster than current methods do.

The experiment, in which sea scallops are pinned in pairs to vertical ropes suspended in the ocean water, exposes the animal to more water flow. That, in turn, causes them to open and close their shells more often to feed and helps their adductor muscle, the part that Americans eat, grow larger through exercise during the scallops three-year seed-to-harvest cycle. Farmers hope the “ear-hanging” method will allow them to develop their test farms into commercial-scale operations, which are needed to keep up with rising consumer demand.

And they hope that three scallop pinning, drilling and cleaning machines that a Maine-based investor is bringing to the state from Japan will help them rein in the high labor costs of ear hanging, so they can turn a bigger profit.

The state has granted a handful of limited leases to test the potential market, tapping into the small, tight-knit network of farmers who already raise oysters, clams, and mussels in leased state waters up and down Maine’s 3,500-mile shoreline. These demonstration projects will help scientists determine which husbandry methods, nutrient mix, hanging heights and water temperature grow the biggest, fastest, and healthiest scallop meats, and if it’s profitable enough to become a commercial aquaculture fishery.

Dana Morse of Maine Sea Grant checks on ear-hung scallops tied to an anchor chain on a mussel raft floating in the Damariscotta River.

Dana Morse of Maine Sea Grant checks on ear-hung scallops tied to an anchor chain on a mussel raft floating in the Damariscotta River.

A bonus? The new method is said to do less damage to the ocean floor.

But the funding agency that is bankrolling the purchase of the $70,000 worth of ear-hanging machinery knows that the business model has to be as sustainable as the scallop fishery.


“That is why we’re stepping in here, to take some of the risk out, to see if what works in Japan will work here,” said Hugh Cowperthwaite, fisheries project director with Coastal Enterprises Inc. (CEI), an investor that specializes in spurring rural economic growth. “We want to rebuild this industry, because to us it is a sustainable source of good protein for a population that is clamoring for it. But for a start-up business in Maine, a small oyster or mussel farmer, we know the economics have to be there, too.”


A decade ago, Maine’s scallop fishery was on its death bed, with commercial landings at their lowest in decades and the state enacting rolling closures of fishing zones in hopes of helping the species rebound.

The fishery bottomed out in 2004, yielding just 54,000 pounds of scallop meat, state statistics show. At prices hovering about $4 per pound, Maine fishermen netted just $218,000 from the sea scallop harvest that year.

The fishery had fallen hard and fast from its peak in 1981, when Maine fishermen landed 3.8 million pounds of scallop meat and earned some $15 million. To stabilize the fishery, the state began surveying the stock and closing zones. They also capped licenses.

Fishermen chipped in, too, using methods developed in Japan to collect wild scallop seed, or spat, in mesh bags suspended in the water where young scallops could grow until they were big enough to release into the wild, thus helping to build up the population.


As a result of these efforts, the Maine sea scallop fishery is rebounding. It has grown from 175,116 pounds in 2011 to 452,672 in 2015, according to the Maine Department of Marine Resources. The value of the scallops themselves has grown even faster, from about $1.7 million in 2011, or about $9.98 a pound, to $5.7 million, or $12.70 a pound, in 2015.

Despite higher harvests, though, the supply of fished scallops has been unable to keep up with demand. To fill in the gap, aquaculture advocates have again turned toward Japan.

“We see this as an opportunity to add another species to what Maine growers are already offering,” said Mark Green, co-owner of the Maine Scallop Company of Portland, which will work with CEI to test out the Japanese ear-hanging machinery. Green is also a professor of natural sciences at Saint Joseph’s College in Standish and a licensed Maine oyster farmer.


Growing scallops in the traditional manner, in trays and cages on the ocean floor, takes time, as much as three years to reach legal size, and lots of labor to keep the shells free from what’s known in the industry as “biofouling,” like barnacle growth, which can prevent the scallop from fully feeding; and predators, like starfish, that like a scallop dinner as much as we do.

Aquaculture researcher Dana Morse checks ear-hung scallops, which are pinned to ropes suspended vertically in ocean waters, about 10 feet below the surface and not too near the bottom. That keeps them safe from bottom-feeding predators.

Aquaculture researcher Dana Morse checks ear-hung scallops, which are pinned to ropes suspended vertically in ocean waters, about 10 feet below the surface and not too near the bottom. That keeps them safe from bottom-feeding predators.

Due to the risk of toxin buildup within the scallop organs, scallops must also be shucked at sea. Only the toxin-free adductor muscle can come ashore. The rest of the scallop, like the shell and guts, are tossed overboard. Sea farmers would like to find a way to sell whole scallops to restaurants for that freshest sea-to-table dish when wild scallops are out of season, but that would require regulatory changes and expensive testing.


According to the latest Japanese methods, vertically pinned scallops are suspended about 10 feet below the surface of the water yet not too close to the bottom, where predators lurk. Because the water – and all of its nutrients – flow freely, the sought-after adductor muscle grows faster than with the less active tray-grown scallops.

Ear hanging is easier on the ocean floor, the primary habitat of the state’s cash cow, the lobster, than wild scallop harvesting, which often comes under fire for disturbing that habitat with their near-shore trawling methods that rake the ocean floor.

There is a catch, though: Hanging requires even more labor than the tray method. To anchor the scallops to the line without damaging the meat, plastic pins must be pushed into the vertical lines and through tiny holes drilled into the hinge of the shell. Unlike many other shellfish, scallops can swim away.

Fortunately, various Japanese machines mechanize much of this labor, from machines that sort juvenile scallops by shell size (which guides hole placement) to the hole drilling itself, from pushing pins through the line and pulling them out again to cleaning the shell.



CEI was recently awarded a $134,000 Maine Technology Institute grant to purchase $70,000 worth of line-pinning, ear-drilling and vessel-mounted shell-cleaning machines and to study their effectiveness on a farmed scallop fishery.


The organization is working with Maine Scallop Company, a joint venture of Green and mussel farmer Peter Stocks, to test the custom-made machinery it is ordering on 1,500 lines in Casco Bay over the next two years.

For example, a team of five people would need about 21/2 hours to drill holes in 300 scallops, Stocks said, while the machine, which can drill two scallop hinges per second, can pierce that same amount in fewer than two minutes, Stocks said.

“It’s the equivalent of going from tilling the soil by hand to tilling soil with a tractor,” Stocks said.

That is the speed and efficiency required to work a farm of several hundred thousand scallops, he said. He and his crew, and even his wife, have pierced their test lines by hand, but that has essentially capped their production scale at about 10,000 scallops.

“That’s not going to grow enough scallops, and generate enough gross revenue, to pay wages for our staff, our insurance and our licensing fees,” Stocks said. “But the Japanese have been amazingly good at creating efficiencies needed to succeed in the market.”

If Maine Scallop Company demonstrates rapid, healthy shellfish growth and profitable returns using the Japanese machines, CEI will explore the concept of a machine-sharing agreement with other shellfish farms, Cowperthwaite said. Neither CEI, the state, Maine Sea Grant or the farmers know what to expect, or if they will have the answers they need to evaluate the viability of the ear-hanging technique and the effectiveness of the machinery here in Maine, under a different government and a different economic regulatory structure.



Cowperthwaite has been spreading the gospel of ear-hanging scallop farming ever since he visited Aomori, Japan in 2010 as part of a commercial fishing tour of Maine’s sister state. This area, which has a climate similar to Maine’s, is heavily dependent on fishing.

The state established a sister relationship with the northern prefecture in 1994, but Maine has had ties to the area dating back to the wreck of the Cheseborough, a Bath-built ship that fell victim to a typhoon off its coast in 1889. Of the 19-man crew, only four survived, but they forged a strong bond with locals that remains today, some 125 years later.

That relationship has led to exchanges of students and technology, including the visit that got Cowperthwaite hooked on ear-hanging scallop farms. This fall, he will lead a tour of Maine sea farmers to explore all facets of the Aomori ear-hanging scallop industry.

Dana Morse, an aquaculture researcher at Maine Sea Grant, visited Aomori back in 1999, and came back with the belief that scallop aquaculture would offer the state fishing industry much needed economic and species diversification. Morse is now studying growth rates, biotoxin accumulation rates, biofouling, and yield and market value of ear-hung scallops at several state-sanctioned lease sites around Maine, including near the Darling Marine Center on the Damariscotta River.

“Since early March of this year we are already seeing very strong growth rates with scallops,” Morse said. “We’re very optimistic.”


Damariscotta is the heart of the state’s shellfish aquaculture industry, where mussels, oysters, and even smaller-scale fisheries, like clams and urchins, are cultivated in state-leased waters. Of Maine’s 110 commercial aquaculture leases, 28 can grow scallops.

But according to Cowperthwaite, only a handful actually do so. He views that as a missed opportunity to grow the state’s aquaculture industry and add jobs, but also to diversify a major state industry that mostly rests on a single species.

“Sea farmers and fishermen are looking for ways to diversify their income and continue to work on the water,” he said. “It’s no secret that Maine’s wild-caught fisheries continue to decline and as an industry we are very dependent on the lobster.”

Green, at least, has been quick to see the potential.

“If the (ear-hanging) project goes as planned, scallops will offer a new way to diversify and firm up the economics of my business,” he said.

Stocks noted that 90 percent of the seafood consumed in the United States is now imported.

“People who live on the Maine coast need to understand the value of aquaculture,” Stocks said. “Scallops clean water. Farming them doesn’t disturb the ocean floor. They are a clean, healthy, nutritious, highly regulated food source. We need them, not just for jobs, but for food.”

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