Source to horse: Harvesters turn Quahog Bay rockweed into equine supplements

Harpswell is surrounded by rockweed.

At low tide, wherever you look along the town’s rocky shoreline (and almost all the shoreline is rocky), you will see this seaweed delineating the boundary between land and water. It’s like a yellow-green ribbon outlining all the town’s islands, peninsulas and ledges.

This is good news for the people at Source Inc., which produces animal and human nutritional supplements whose main ingredient is dried rockweed harvested in and around Harpswell’s Quahog Bay.

Source’s processing plant is in Brunswick, but its seaweed harvesting boats operate from Bethel Point, where Ridley Cove and Quahog Bay come together.

While the company was founded in 1975 and is still owned by Susan Domizi, a Connecticut resident, Source’s identity is firmly anchored in Harpswell.

Bonnie Tobey is Source’s operations manager. Her brother, Greg Tobey, is general manager. Both grew up on Harpswell’s Little Yarmouth Island, just southwest of Bethel Point, where their seaweed-collecting boats are moored during the harvesting season.

“The island has been in the family since Aug. 5, 1859,” Bonnie Tobey said.

Tobey was in fifth grade when her parents decided to move full time to Little Yarmouth Island, even though no one had lived there year-round in more than 50 years. “A lot of people said it couldn’t be done,” she said.

“We’re about as Harpswell as Harpswell can get,” she said. “My whole life has been around the water. Seaweed and salt water are pretty much in my veins. I had a boat long before I had a car.”

She still regularly drives a boat, one of the three harvesters owned by Source. Tobey and her brother are the primary operators of the vessels.

A gentle harvest

These boats are not pretty to look at. Instead of the gentle curves of a lobster boat’s hull and gunwales, these raft-like vessels are all flat surfaces and right angles, with a piloting station perched on deck, a cutting head at the bow, and a large mesh bag attached to the stern. While not elegant, they are meant to be kind to the environment.

Domizi, who attended Colby College and has a strong attachment to Maine, wanted Source’s boats to be as environmentally friendly as possible. So she asked her late husband, engineer David Domizi, to design them.

The circular cutting head points straight ahead rather than down. This means the harvester only takes seaweed at or near the surface. The seaweed, which attaches at its base to rocks or ledges, is covered with nodules. (Rockweed’s scientific name is Ascophyllum nodosum, the last part coming from the Latin word for bumps or nodules.)  The buoyant nodules pull the strands toward the surface as the tide rises. So the boat’s cutting head only removes the ends of the strands rather than harvesting their entire length.

The cutters “come across the top and trim it,” Tobey said of the rockweed. “Our boats are incapable of cutting any lower. They can’t damage the resource.”

As the boats trim the seaweed, a pump propels water carrying the bits of rockweed through an 8-inch plastic pipe leading to the stern. There, the stream of water passes through a mesh bag that captures the seaweed while allowing the water to pass through.

Traditionally, rockweed was gathered by raking. That usually meant gatherers going out at low tide and collecting the entire plant, along with many of the marine organisms harboring within, such as mussels, crabs and periwinkles.

“That’s an awful lot of bycatch,” Tobey noted. “Susan is an environmentalist. That was unacceptable to her.”

The design of the boats has largely eliminated that problem, according to Tobey. The cutting heads “are not going deep enough to get crabs and such,” she said. “Our bycatch has dropped to almost nothing.”

Beyond the design of the boats, Source strives to protect the rockweed itself through sustainable harvesting practices.

For example, rockweed reproduces by releasing spores when water temperatures start to rise in the spring. Source does not send its boats out to collect seaweed until this period of reproduction has ended.

Once Source’s boats have collected rockweed from a section of shoreline or ledge, that area will not be visited again for three years. “We rotate our crops just like a farmer,” Tobey explained, by leaving an area idle for two out of every three years.

A recent University of Maine study found that commercial harvesting seems to have a limited impact on seaweed beds, according to a university newsletter. The study found that “the practice (of seaweed harvesting) has a smaller impact than previously thought,” UMaine News reported.

“On average in the study, rockweed biomass fully recovered one year after harvest but the height remained lower where harvest occurred,” the newsletter said.

The study, published in the Journal of Experimental Marine Biology and Ecology, looked at 38 sites along the Maine coast, including Harpswell.

The area constituting Source’s “farm” is relatively small. “Mostly in Quahog Bay, that’s our home,” Tobey said. In some years, they will range as far as Middle Bay to the west or the New Meadows River to the east, but “primarily we’re in Quahog,” she said.

Domizi chose Harpswell as the focus of Source operations because of its long coastline — at more than 200 miles, the longest of any town in Maine. And because her brother was a professor at Bowdoin College, she was familiar with the area.

‘Beautiful light-green cornmeal’

While Source’s gathering of rockweed occurs in Harpswell, the processing takes place in its facility on Industrial Parkway in Brunswick. The bags of harvested seaweed, which can weigh up to half a ton, are plucked out of the water at Bethel Point by a boom truck, which delivers the bags to Brunswick.

For reasons of freshness, each bag is processed at the plant within 24 hours of its harvesting. The seaweed is weighed and hand-sorted to remove any extraneous material. It is then placed in a dryer, where it is closely monitored. “You want to dehydrate it without cooking it,” Tobey explained.

Finally, it is passed through two hammer mills. What emerges looks like “beautiful light-green cornmeal,” she said.

This seaweed meal still needs to be blended. Rockweed has different nutritional profiles depending on the time of year. Because of that seasonal variation, meal from seaweed collected at various times in the harvesting season is carefully blended to produce a consistent product. Small amounts of other kinds of seaweed, also collected locally, are added to create different products.

Source’s primary product is a food supplement for horses. In the 1960s, Domizi was training a horse for competition in the Olympics. The health of the horse, named Hull, began to decline. She began investigating various natural food supplements. Her quest led her to develop a food supplement made with rockweed. It seemed to restore Hull’s health. When other horse owners heard of the results, they were impressed. Thus was Source born.

Today Source sells five versions of its equine supplements, including for hoof health, for older horses and for weight gain. There is also a line of human supplements, as well as one for dogs.

Driven largely by word-of-mouth marketing, the company now has annual sales of about $1 million, Tobey said. In addition to Tobey and her brother, the company employs one other full-time worker and two part timers in Brunswick.

Court ruling has ‘profound impact’

Almost 50 years after its founding, Source is still going strong. But there are challenges ahead. In 2019 the Maine Supreme Judicial Court made a decision that has cast a shadow over access to seaweed in the intertidal zone.

Under Maine law, the intertidal zone is open to people engaged in fishing, fowling (bird hunting) or navigation. But in Ross v. Acadian Seaplants, the court ruled that gathering seaweed does not constitute fishing and that adjacent landowners can claim title to the seaweed in the intertidal zone.

That ruling has had “a profound impact,” Tobey said, by creating what she believes is a misunderstanding among landowners about their ownership rights in the intertidal zone.

“Some upland owners are denying access to what they believe is their rockweed,” she said.

Source used to run three shifts at its Brunswick plant. It now operates only two, she said.

The company’s boats continue to collect seaweed in most of the places where they have in the past, but not in places where the adjacent landowners have said they are unwelcome. “Anyone who has objections, you stay away from,” she said.

Since 2020, Tobey has served as president of the Maine Seaweed Council. So she serves not just as an advocate for Source, but for all members of the council.

According to its website, the council was formed in 1993 by a group of harvesters, as well as business owners, researchers and consultants, to address growing concerns within the industry.

One of the most immediate concerns of harvesters is that they will be accused by landowners of criminal trespassing when collecting seaweed. Tobey hopes that the next session of the Maine Legislature will approve a bill that would shield harvesters from accusations of criminal trespassing. But even if that bill passes, landowners would still be able to file civil suits against harvesters for trespassing, she said.

John Gormley, of Cundy’s Harbor, worked as a reporter and editor at The Baltimore Sun, the Portland Press Herald and Professional Mariner, among other publications. He writes for the Harpswell Anchor about nature, particularly the marine environment.