Kelp at the Crossroads: Should Seaweed Farming Be Better Regulated? | Civil Eats

Kelp at the Crossroads: Should Seaweed Farming Be Better Regulated?

kelp farming

On Vancouver Island, seaweed is abundant, diverse, useful, and symbolic. Indigenous peoples have used it for centuries for food preparation, fishing, and as a cultural and spiritual touchstone. On the island’s southwest coast, Dr. Louis Druehl started farming and researching kelp in the late 1970s and says he has dedicated his life to it “and loved every minute.” He mentored seaweed farmer Kristina Long, who now grows bull kelp over about 40 acres, and harvester Amanda Swinimer, who wades out into waist-deep water at low tide to carefully hand-cut blades of winged kelp in just the right spot to ensure regrowth.

These tiny operations barely create ripples within the vast coastal landscape, but kelp—here and elsewhere in North America—is at a crossroads.

In recent years, seaweed has been promoted around the globe as an overlooked, multifaceted climate solution: a sustainable food and biofuel source, a feed that reduces methane emissions from cattle, and a tool with the potential to absorb massive quantities of carbon from the atmosphere (although much more research is needed to determine how farms might actually contribute to sequestration). As a result, companies looking to capitalize on those promises are turning up in far-flung coastal communities with big plans.

Take Cascadia Seaweed. The company arrived on Vancouver Island soon after it was founded in 2019, and set a goal to farm 1,200 acres of the ocean there by 2025; its larger “stretch goal” is over 6,000 acre. In Alaska, Seagrove Kelp Co. has 127 acres in operation and 700 in the permitting phase. And in Maine, the continent’s seaweed-farming hub, Running Tide’s vision involves millions of biodegradable buoys attached to lines of kelp offshore.

Many see the movement toward larger operations as exciting evidence of progress. “We have all these global problems and no solutions on land. Seaweed is the greatest untapped resource that we have,” said Vincent Doumeizel, the food program director at the innovation-focused charity Lloyd’s Register Foundation. Doumeizel co-authored The Seaweed Manifesto in 2020 to draw attention to how scaling up the industry outside of Asia, where 99 percent of the world’s seaweed is already grown, can accelerate progress on multiple United Nations Sustainable Development Goals.

At the same time, seaweed farmers, harvesters, and advocates in British Columbia, Maine, and elsewhere are concerned. They say that as companies with no experience in their coastal ecosystems or the complexities of farming kelp go big and move fast, the industry risks replicating the early mistakes of finfish aquaculture, which resulted in a number of environmental disasters. To prevent repeating historic mistakes, they are fighting to establish local rules regarding issues such as farm size and location, native seaweed genetics, and permit ownership.

In 2021, advocates in Maine created the Seaweed Commons to create networks of small-scale ecological harvesters and farmers that could share information and resources; they also conducted a panel at a Slow Fish conference called “Gardens or Monocultures? Seaweed Cultivation at the Crossroads.” In March, Lloyd’s Register Foundation also launched the Safe Seaweed Coalition to fill in gaps in food, environmental, and operational regulations around the world.

“I’m absolutely thrilled that seaweed is coming into people’s consciousness and awareness . . . as an absolutely critical component of global climate and global health and the health of the oceans,” said Amanda Swinimer. “The part that concerns me is that a lot of people are seeing dollar signs. It’s being said that kelp farming is going to save the planet from climate change. Well, wild kelp is already saving us from worse climate change, and if we mess with that, we’re gonna be in big trouble.”

Is Bigger Better?

In Maine, resistance to the expansion of industrial-scale aquaculture operations is mainly focused on salmon and other finfish farms, but seaweed is quickly becoming part of the conversation. In April, lawmakers in the state held a public hearing on a bill that would limit the size of aquaculture leases and make other changes to the state’s regulatory processes..

Severine von Tscharner Fleming operates a small organic farm on the southeast coast of Maine, where she grows fruit and farms and harvests wild kelp, and is a creator of the Seaweed Commons as well as the young farmer group, the Greenhorns. At the hearing, she said, the big debate was around whether Maine should allow leases for seaweed farms as large as 1,000 acres. “The Maine Aquaculture Association said, ‘Yes, we must have it this big, we need this industry for jobs and coastal prosperity,’” she said. “It was yet another slap in the face for those of us who believe we need a regulatory context that will enable a right-scale sector to emerge.”

But when it comes to kelp, what is the right scale?

In Asia, vast coastal farms can produce millions of metric tons of seaweed per year. In Maine, farms most often occupy just a handful of acres. One of the biggest seaweed companies in the state reported a record harvest in 2020 equivalent to about 360 metric tons, grown across two dozen different farm sites.

Companies looking to grow kelp for biofuels, fertilizers, and animal feed are going to need to scale up considerably to be profitable compared to the primarily small companies making food products operating in Maine right now, said Carrie Byron, a researcher who studies sustainable ecological aquaculture at the University of New England (UNE) and is currently studying the ecosystem benefits of seaweed farms. To scale up, they’ll need to move offshore in order to find space that isn’t impacted by other coastal activities, like lobster fisheries, she says.

“We need to figure out the engineering. We don’t [yet] know how to grow seaweed on super large scales in a very dynamic [offshore] environment, where there’s much more wave energy and susceptibility to storms and you need bigger boats and more fuel and bigger anchors,” she said. Another research team at UNE is working on studying these questions with funding from the U.S. Department of Energy.

In general, Byron said, it’s clear that seaweed produces ecosystem benefits and fights ocean acidification, and so far, the farms have an incredibly low footprint on the ocean. “It’s a completely different ballgame [compared to finfish aquaculture],” she said. “The impacts are so minimal . . . there is very little potential for harm.”

Even so, there are plenty of unanswered questions and concerns as more companies enter the industry and farms increase in size. One such question involves genetics: While Maine and British Columbia both have rules in place to only allow native varieties of seaweed to be grown in state waters, even within species of kelp there are variations by region, and experts say more research is needed to determine the impacts of using seed with varied genetics in different locales.

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“Phycologists [seaweed scientists] have studied bull kelp populations on the west coast of the island [compared] to inland areas, and the populations are genetically distinct. Populations of seaweed have evolved to adapt to the conditions where they are growing,” said Swinimer, who is also a marine biologist. “So that’s a big concern if you’re taking the genetics of a population and then spreading them all around Vancouver Island.” Researchers have already tracked contamination of wild seaweed with farmed seaweed genetics in China.

As a steward of wild kelp, Swinimer is also worried about companies placing farms in areas where wild varieties are abundant and might compete with farmed kelp for nutrients. Larger farms can also shade the bottom of the ocean, she said, affecting important ocean grasses and other organisms. And when aquaculture operations fail or move to new locations, they often leave behind marine debris that can affect other wildlife.

As Cascadia gets established on Vancouver Island, CEO Michael Williamson said the company is considering those issues when determining scale and siting for its farms. “Anybody can get on Google Earth and see what they’re doing in China and Korea. They’ve turned whole bays and regions into seaweed [farms], and that works for them. That won’t work as well in the North American context, and it won’t work as well in the British Columbia context,” he said. Instead, Cascadia is looking at placing a series of “modules” along the coast, up to around 120 to 250 acres to build up to its larger footprint.

But others in the region are concerned about the rapid growth and scale, given the company’s lack of a track record.

Kristina Long, a marine captain by trade, studied with Louis Druehl and spent about four years “de-risking” her seaweed farm before ending up with a thriving operation that now spans about 44 acres on two sites and produces bull kelp for food and livestock feed.

“These are people that are completely new to the marine environment and new to aquaculture . . . and they’re also not wild harvesters, so they’re not familiar with the coast or the ecosystem,” she said. “We’re all mystified by the approach because it’s very fast, and they’re not proving the concept or business model, they’re just going for it.”

Williamson positioned that ethos as a positive driving force. “We incorporated the company and said, ‘You know, we have this great plan to become North America’s largest ocean cultivator of seaweed,” he told Civil Eats. “We looked at each other and said, ‘Who knows how to grow seaweed?’ Nobody. So, we also realized we had to get a farm in the water right away. Otherwise we’re just a paper company. We have to walk the talk.” Cascadia has since added marine phycologists and conservation biologists to its staff, and it turned to Druehl to teach the company’s team how to grow seed, which it is now doing in-house.

Williamson said the company’s first commercial harvest this year produced a modest 20 tons of seaweed from five farms ranging from 2 to 20 acres. The crop failed at one site. Cascadia’s team froze the kelp, he said, and is currently turning it into five plant-based food products that will launch soon. Druehl, who is now on the board of directors, is supportive of its efforts to scale up and says he sees “a lot of good coming out of” the company’s efforts to make seaweed a bigger part of diets and climate conversations. “In fact, my biggest fear is that they fail, because there’s so much hype right now . . . and it would set everybody back,” he said.

Indigenous Involvement

Frank Voelker’s skepticism about the growing industry is about the potential for a different kind of failure—the failure of big seaweed companies to deliver real economic benefits to the First Nations bands on whose territories they are operating. Voelker has been the economic development officer for the Kwiakah First Nation, based in Phillips Arm in British Columbia, for 16 years. 

One of Cascadia’s major selling points is that it plans to work in partnership with the many First Nations bands in the region, essentially offering contracts in which the bands would own and operate kelp farms as part of a network of producers selling to the company. Williamson said there is a “tremendous” amount of interest from First Nations, so much so that the company can’t yet accommodate it.

Eventually, the plan is to design and install the farms and provide seed, “and then after a couple of years, the model is to have the local community take over all the work and we just buy the crop from them,” he said. “In a perfect world, about two-thirds of our farms would be owned and operated by First Nations community partners and about one-third would be company-owned and operated.”

Voelker explored the opportunity for the Kwiakah Nation in several conversations with Cascadia’s leadership but said he came away with the sense that while the team’s intentions were good and they operated with respect towards First Nations, they were essentially putting the cart before the horse. Without logistics or infrastructure in place to transport the kelp to processing, he didn’t see how it could work in his band’s territory. He also questioned the number of lease contracts the company was seeking before having a food product ready to market and the potential for profit at the farm scale.

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“The money is in the value-added process. Here, the First Nation is supposed to grow and supply the resource, and the money is where the value is being added, with the company turning the crop into food,” he said. “One problem I have for my fellow neighboring Nations in economically difficult areas is that finfish aquaculture is going down the drain right now. That economic benefit is going away, and to think that revenue can be replaced [with kelp] is a pipe dream.” Voelker is leading efforts in Kwaikah territory to build a First Nations-owned kelp farm for the band’s own research on conservation, especially in quantifying carbon sequestration value, which he says is also widely speculative at this point.

Other First Nations, like the Klahoose, were actively involved in aquaculture production and have been able to simply add kelp farming onto their existing operations. They have already begun working with Cascadia and leaders have expressed excitement at the possibilities.

Writing the Future Into Regulations

Advocates across the board said that at the end of the day, they just want everyone to have to play by rules that protect the oceans and Indigenous communities. And they don’t think those rules exist yet.

“It’s new, so people are scared, and in some ways, we have to be cautious,” said Doumeizel, who is working with the Safe Seaweed Coalition to start developing standards that states around the world can look to for guidance on developing local regulations. More research is crucial, Doumeizel said, and if the industry can answer more of these questions and develop better regulations, he believes it will serve its growth. “Safety standards have a strong convening power,” he said, in that companies and individuals with varied interests and opinions may be driven to work together.

As Canada develops a Blue Economy Strategy to guide sustainable development for its coastal regions, Long and Swinimer were part of a coalition that submitted recommendations that included restricting the use of seed to specific zones determined by Druehl to represent distinct genetics and limiting lease sizes for new farmers “until proof of concept or direct-to-market traction is demonstrated.” They also included several recommendations to ensure First Nations communities are included in the industry’s development in ways that are collaborative and ethical.

Voelker said that he’s watched the forestry and salmon industries destroy First Nations territories while also keeping a stranglehold on regulatory processes. “A standard for [kelp farming] needs to be developed . . . where the government is at the table, the Indigenous governments are at the table, and environmental NGOs are at the table, but not the industry,” he said. “The only way to get it right is to not have the industry in the room. If they get a seat at the table, the problems we have with fish farming, we’ll have the same with seaweed in 10 or 15 years.”

In Maine, von Tscharner Fleming is fighting to get regulations in place that she hopes will ensure more of the state’s future kelp production will be “locally owned, conservation-minded, appropriately sized, and [using] native genetics.” Her group wants the size of seaweed farms to be limited and for leases to be non-transferable, so that companies can’t come in and buy up space from previous lease holders.

If nothing else, as money and industry move in, they want the voices and concerns of those who have been stewarding seaweed resources for years to be represented.

“So much of this is: Who is saving the world harder and faster with sexier videos?” von Tscharner Fleming said. “That lends itself to these grandiose solutions, when we should be focusing on restoring our fisheries, restoring our kelp beds, and reviving our coastal ecology. This is a really powerful food . . . . but let’s be careful. We have a situation in which this glamorous, save-the-world narrative—which I’m part of—is just an exploration phase for industry.”

Lisa Held is Civil Eats’ senior staff reporter and contributing editor. Since 2015, she has reported on agriculture and the food system with an eye toward sustainability, equality, and health, and her stories have appeared in publications including The Guardian, The Washington Post, and Mother Jones. In the past, she covered health and wellness and was an editor at Well+Good. She is based in Baltimore and has a master's degree from Columbia University's School of Journalism. Read more >

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  1. Clifford Goudey
    It is fascinating to hear someone engaged in the harvest of wild seaweed try to lecture those committed enough to actually build an ocean farm. Natural kelp beds are limited by depth and growth substrate but are essential to local ecosystems and should be protected. Properly sited kelp farms strengthen ecosystems.
    I sense this all boils down to fear of competition.
  2. Gabriel
    How do we define seaweed at a local scale?
    Those of us who work in genetics know that the geographical scale we are talking about depends entirely on the genetic marker (and criteria on the analysis) that is used.

    What will happen to the management plans for these areas?
    There will be crop rotation plans (in time and space) to let "rest / recover" the growing area.

    What will happen to the cultivar improvement plans?
    Because the domestication of algae is essential, especially considering small farms and/or short growing seasons.

    And about genetic improvement? (even before GMOs)
    If sterile seaweeds are achieved, can they be grown in other areas? In that case, there is no risk of spread (assuming there is no spread by fragmentation, as occurs in various red algae)
    A harvest prior to maturation or generate polyploid or hybridization between species, or other techniques that do not require gene editing, would suffice?
  3. In 1978 I worked for the Ministry of the Environment, Marine Resources Branch. I was part of a very exhaustive study that took place in Port Hardy. Dozens of divers, scientists, sample harvesters and support staff took part for an entire summer. It was a very large and expensive study. After all that, it was determined that the "Kelp Based Food Web" habitat was too vital to the marine eco-system to grant harvesting licences. What happened to that wisdom?

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