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From Maine’s warming waters, kelp emerges as a potentially lucrative cash crop

With warming oceans threatening lobstering, kelp farming could become a major industry

Colleen Francke cut off fresh kelp from a rope as it is fed onto her boat from the sea farm below in Falmouth, Maine. Francke's husband, Brent Nappi, cleaned the rope as it works its way toward him.Erin Clark/Globe Staff

FALMOUTH, MAINE — One bright, brisk morning last month, Colleen Francke steered her skiff a mile off the coast of Falmouth and cut the gas. A few white buoys bobbed in straight lines on the water. Francke reached down and hoisted a rope.

She has been lobstering for a decade and a half, she says, but as climate change warms local waters and forces lobsters northward, she’s been finding it harder to envision a future in that industry.

So, for the last two years, she’s been developing a new source of income. Heaving the rope aloft, she showed off her bounty: ribbons of brown, curly sugar kelp, raised on her 10-acre undersea farm.


Kelp, a seaweed more often thought of as a nuisance by fishermen, is emerging as a potentially lucrative crop, hailed for its many uses as a miracle food to an ingredient in bioplastics to a revolutionary way to feed beef cattle. And Maine officials, confronting a likely decline of the state’s iconic lobster fishing industry in coming decades, are now looking to kelp farming as a possible economic and environmental savior.

The state is working with local institutions to support training and grants for entrepreneurs such as Francke willing to move into kelp farming or other aquaculture ventures. It also labeled kelp a “natural climate solution” in its recently-released Climate Action plan. The goal, officials say, is to dramatically expand kelp farming as part of a reinvention of Maine’s seafood industry — and imagining a future in which kelp from Maine is held in something akin to the esteem that Maine lobster is now.

“We think kelp and other aquaculture offer…a connection to a next generation workforce and innovation for a heritage industry,” said Heather Johnson, Maine’s commissioner of economic and community development. “That is key to the longstanding sustainability of the existing supply chains.”



Rich in nutrients and vitamins, kelp has long been consumed as a staple in Asian cultures. In the last several years, it’s been increasingly incorporated into health, beauty, and food products in the United States. The Food and Agriculture Organization of the United Nations named seaweed farming the fastest growing sector in aquaculture, and the research firm Global Market Insights estimates the worldwide market for seaweed will grow to $85 billion by 2026.

Freshly harvested kelp on the deck of the Linda Kate, a lobster boat turned kelp farming boat operated by Colleen Francke. Erin Clark/Globe Staff

Now 35, Francke helped build the first kelp farm in Maine a decade ago. Today the industry has taken off in the state, with over 100 farming sites now dotting the coast. It’s a relatively simple and remarkably sustainable process: There are no inputs like fresh water, fertilizer, or feed. Fishermen place spore-holding sorus tissue along lengths of rope and submerge them, letting Mother Nature do the rest. Just 4 pounds of sorus can seed 30,000 pounds of kelp for harvest.

Maine kelp farms in 2020 produced 450,000 pounds, nearly double the harvest of just two years before. This year they’re on track to bring in more than 800,000 pounds, and, in so doing, are leading the nation in this nascent industry, which is seeing some farms pop up in Alaska and on the West Coast.

But that’s a fraction of what the Island Institute, a community development corporation in Rockland, Maine, that has funded aquaculture business development programs in the state, estimates is possible. By its calculations, that figure could soar to nearly 6 million pounds by 2035. But even those numbers are dwarfed by China, which, according to the UN, produced more than 14 million tons of farmed seaweed in 2017.


Climate change has warmed Maine’s coastal waters by 0.11 degrees Fahrenheit a year over the past three decades, with the Gulf of Maine warming faster than 99 percent of the global ocean. It’s made the lobster industry more volatile, and has decreased catches of groundfish, shrimp, or soft shell clams that lobstermen could rely on in an off year, said Susie Arnold, a marine scientist at the Island Institute.

Kelp farming, she said, offers lobstermen additional off-season income, using equipment they already have on hand. There’s also the added benefit of kelp’s “halo effect”: it sucks up carbon dioxide in the water where it grows and reduces acidification and nutrient pollution in the state’s coastal waters.

“We have actually found that if you grow your shellfish in close proximity to a kelp farm, they can have thicker shells, denser shells, and they’re harder to break,” said Arnold.

The challenge now, she said, is convincing US consumers that kelp is not just a way to diversify one’s diet but also a way to help fight climate change.

Francke, left, laughs with Courtney Boyd Myers, co-founder of AKUA, as she tries a piece of raw kelp, freshly harvested from Casco Bay. Erin Clark/Globe Staff

“Americans aren’t necessarily used to eating seaweed. And in order to change hearts and minds about that, especially people who care about climate change, it’s really important to sell the product in that way,” said Arnold. “It’s good for these local businesses. It’s also — and I mean it — truly is good for the planet.”


It may help that Maine’s appetite for kelp farming comes as the country’s food establishment has been questioning its relationship with meat. Citing the beef industry’s contributions to climate change, Epicurious, the ubiquitous Condé Nast food blog, recently announced that it had ceased publishing recipes with beef, and the acclaimed New York restaurant Eleven Madison Park announced in May that it was switching to an all-vegan menu.

Francke sells most of her harvest to a local startup called AKUA that makes kelp jerky and this summer released a kelp burger that was favorably reviewed by the New York Times and Bon Appétit.

Advocates are hoping kelp can become another buzzy alternative protein with a sustainability aura that could bring in millions of venture funding, such as faux burger brands Beyond Meat and Impossible Foods.

But, that’s “just the tip of the iceberg in terms of what we can do with kelp,” said Briana Warner, the CEO of Atlantic Sea Farms, the largest processor of kelp in Maine. “We’re seeing innovation in bioplastics and kelp-made textiles, food additives, and animal feeds. Food is just the start... the possibilities are really endless.”

Bioplastics, which are typically made from renewable sources such as kelp, are just one way seaweed could have a huge impact on climate change. A subset of the industry is also looking at whether kelp farming could be used to sequester carbon and reduce greenhouse gases in the atmosphere. And researchers at the University of California Davis have found that feeding seaweed to beef cows can help reduce the amount of methane they produce by 82 percent.


But to get to the point where Maine could actually produce enough kelp to sustain any of these big ideas means wading into some fraught territory.

Maine’s Department of Marine Resources oversees the distribution of aquaculture leases in the state, and there’s been increasing pushback from local fishermen and wealthy waterfront landowners about plans for the rapid expansion of such farms along the coast. Most of that opposition has been directed at large fisheries where salmon or other species are grown in pens, but kelp farms, because they operate using the same aquaculture lease permitting system, have become ensnared in those debates.

Francke, who has applied to the Maine Department of Marine Resources to expand her farm from 10 acres to 100, which would be the largest in the state, has become a target of critics. If her application succeeds, said Crystal Canney, executive director of Protect Maine’s Fishing Heritage Foundation, a foundation opposing the expansion of aquaculture, you’ve “lost all that bottom to lobstering. You cannot put lobster traps in that area — you get tangled.”

Matt Cranston ties off ropes of kelp during a harvest for Francke's kelp farm. Erin Clark/Globe Staff

Canney claims that over the past 15 years, Maine has haphazardly increased access to aquaculture leases and now allows farmers to lease more than 1,000 acres of water for up to 20 years. In April, a state lawmaker proposed legislation that would limit the size of aquaculture leases and change how leases are transferred in Maine.

“Kelp has great potential for the state of Maine, no question about that,” Canney said. But letting a kelp farmer such as Francke expand to 100 acres could end up displacing lobstermen in the process, she argues. Soon, she said, “10 more Colleen Franckes can do the same thing in the same area because lease approvals are at 97 percent.”

Entangling things further is new statewide legislation passed in 2019 that allows homeowners with waterfront property in Maine to weigh in on the aquaculture permitting process — offering testimony and presenting witnesses at public hearings.

Aquaculture advocates say that many wealthy homeowners are paying top dollar to hire lawyers to keep oyster, mussel, or kelp farms away from their waterfront views. “The landowners don’t want to look at it or smell it,” Sebastian Belle, the executive director of the Maine Aquaculture Association. “They will often lawyer up and throw everything they can at the situation and see what sticks.”

Francke boards the lobster boat she now uses to farm kelp in Casco Bay, which is then sold as a healthy, trendy, sustainable product that can be used in beauty products and alternative protein foods like kelp jerky and burgers. Erin Clark/Globe Staff

Belle says such wealthy backers are behind the Protect Maine’s Fishing Heritage Foundation, which aligns itself with some lobsterman to oppose such farms. But he argues that such action could be the fishermen’s own undoing.

“A fundamental demographic shift is happening on the coast of Maine and COVID has accelerated that,” he said. “The gentrification of the Maine coastline is really pushing working waterfront families out.”

“Aquaculture is really the only way left open for a traditional working waterfront family to add to their income,” he said.

Should her expanded farm come to fruition, Francke says she’s designed it with enough space between her lines that lobstermen could steer their boats through it.

“Colleen is one of our newer farmers and she has some different approaches,” said Belle. “She’s more interested in going big than some of the other farms are.”

And that’s made her among the first to experience growing pains in the industry.

“I think people look at that 100-acre number and they pass judgement before they even know what the design of the lease is,” Francke said. But what concerns her more is that if she’s thwarted in her effort to scale up, it means the industry won’t grow, and she’ll have less of an impact on climate change.

“I look at growing this farm in one of these uber-rich communities, and look at these McMansions with these neon green lawns, and I know my farm is only going to do so much to combat what it’s like to maintain and heat that home and the chemicals on that lawn,” she said.

She’d love to sustain herself financially through kelp farming, but her larger goal is to inspire others to do their part.

“If one individual can actually make a positive change,” she said, “there’s something else everyone can be doing to make their own positive impact toward our climate problem.”

Janelle Nanos can be reached at Follow her @janellenanos.