Could the tide be rising for American aquaculture?

At California Sea Grant in Moss Landing, the aquaculture specialist Luke Gardner stands by a vat of culinary seaweed. Boosters hope that seaweed can follow soybeans’ rise from obscurity to agricultural powerhouse. California Sea Grant

By Sophia Siegel

Luke Gardner strides silently among rows of burbling, black drums, and a flat generator hum. Pausing at a drum, he reaches down into the impenetrable white glare at the water’s surface. The hand disappears; the guttural air pipes sing. Then, in his damp palm, a little red web materializes like spun glass. “Dulse,” he says, “tastes like bacon.” 

Gardner is an aquaculture extension specialist at California Sea Grant, based out of the Moss Landing Marine Lab Aquaculture Facility. At Sea Grant, Gardner speaks the languages of academia and industry, helping scientists direct research toward areas of need. Privately, he has always loved aquaculture and nurturing things. 

The type of onshore aquaculture Gardner oversees at Moss Landing is novel in California, but seaweed farming is not new to the American West. For millennia, Pomo Indians, Yurok, Sinkyone, and other Northern California tribes harvested seaweed for its culinary and medicinal uses. In the modern food and cosmetics industries, seaweeds are hidden in places you’d never expect them: in ice creams, toothpaste, beers, bread, jams, soups, and cosmetics. 
Likewise, countries in Asia have cultivated seaweeds for thousands of years. Korean seaweed farms are so big (about 220 million acres), they are visible from space.

Seaweed’s environmental virtues are manifold, but its economic virtues are hard to see.

But on any inventory of agricultural products in the United States, seaweed’s place is vanishingly small. Its environmental virtues are manifold – seaweed can purify water, promote biodiversity, and mitigate the impacts of climate change, like erosion or acidification. But its economic virtues are hard to see. That’s a major reason that western seaweed farmers are late to the game.

Could the soybean industry serve as a model?

To get economic payoff for their investment will require patience and persistence. Long-term market trends can be hard to identify in a nascent industry. Yet, there have been other obscure agricultural products that were transformed into mainstream commodities. Take soybeans. In decades, they went from being a minor cover crop to a primary global product. 

Like soy a century ago, seaweed has not yet been embraced in the U.S. as a food crop.

That change didn’t arise from a sudden shift in culinary preference. It came from decades of genetic modification, industrialization, and experimentation in diverse industries. After the first American soy-processing plant opened in Decatur, Illinois in 1922, new mechanical farming techniques in the mid-century established the industrial use of soybeans for oil and animal feed. In 1996, the U.S. Department of Agriculture approved Monsanto’s first genetically modified soybeans, designed to be resistant to herbicides. This innovation revolutionized soybean farming, leading to increased yields, reduced production costs, and a broad diversification of uses.

Like soy a century ago, seaweed has not yet been embraced in the U.S. as a food crop. Even if Americans did develop an affinity for consuming seaweed, competing with Asian producers would likely be impossible. “In commodity industries [such as seaweed]” Gardner said, “they look for the cheap stuff. So, if you’re going to grow the same seaweed that they’re growing in China for the same market, it would be tough to make any money.”

For a tiny domestic seaweed industry, nowhere to go but up

The United States currently produces only 0.01 percent of global seaweeds.  

The U.S. seaweed industry is now mimicking soy’s progression-through-innovation approach. Though scaling it up will be challenging, there’s room for growth, given that the United States currently produces only 0.01 percent of global seaweeds.  

In Seaweed State of the Industry, an article published last year in the seaweed-industry newsletter Phyconomy, Steven Hermans reported that investors in seaweed production put 83 percent of their funds into four sectors: biorefineries to make fuel; bioplastics; food products; and livestock feed; the last of these is intended to reduce methane emissions. Of these, the two most promising subsectors, methane reduction and biorefinery, require far more raw biomass than is being cultivated now. 

Seaweed’s contribution to cattle feed has generated the most attention. California has more dairy cattle than any other state – but ruminant livestock produce methane (an ozone-depleting and heat-trapping gas) as a byproduct of digesting feed.

In the last three to five years, dairy research groups have begun examining the methane-curbing effect  of incorporating seaweeds into cattle diets. The active ingredient in seaweed is bromoform, a volatile gas emitted by all macroalgae, and it’s effective in very small concentrations. One experiment using a diet of 0.5 to 1 percent seaweed reduced methane emissions by as much as  half.

At the site of the experiment, the U.S. Dairy Forage Research Center in Madison, Wisconsin, the researcher Kenneth Kalscheur works to evaluate how forage (feed) composition affects cattle health. Modifying nutrition to reduce methane output has been an area of interest in the dairy world for more than a decade, “but in terms of it being a hot topic,” Kalscheur said, “it’s probably been in the last three to five years.” 

Cattle feeding studies can last for eight weeks or longer, with up to 50 cattle per trial. To conduct an eight-week study on 20 cattle feeding 0.5 percent seaweed dry matter, Kalscheur calculated he would need 14,560 pounds of wet seaweed biomass. To feed 90 million American cows a diet of 0.5 percent seaweed for eight weeks would require a staggering 72 billion pounds of seaweed. In comparison, a generous estimation based on recent years’ annual yields are in the low six-figure range.

The U.S.’s tangled history of industrial seaweed production

Industrial uses of seaweeds are not unprecedented in the United States. During World War I, the U.S. military harvested kelp from the Pacific coast and fermented it to replace German potash, a fertilizer and important component of gunpowder. The energy industry began experimenting with hydrothermal liquefaction (HTL) in the late 1960s, and it is now a promising alternative energy technology for the quick conversion of seaweed into biofuels. The HTL process converts organic matter into liquid biofuels by applying high pressure and temperature, simulating the natural geological conditions that form fossil fuels. The resulting bio-oil produced can be processed by existing fossil fuel infrastructure for oil refining. Fermentating giant kelp takes slightly longer (three days), but produces a distilled pure ethanol equivalent to corn ethanol without its considerable land and freshwater demands. 

However, massive quantities of seaweed are needed for energy applications. Cindy and Brian Wilcox, co-founders of the company Marine BioEnergy, estimate that it would require cultivating 0.5 percent of the ocean surface (about 446 million acres) to produce enough biomass to replace all the liquid fuels needed for long-haul vehicles like jets, ships, and trucks worldwide. For comparison, in 2021 NOAA released a report identifying 10 aquaculture opportunity areas in California coastal waters, covering a total of 16,000 acres.

Though producing sufficient seaweed for new industrial uses will be challenging, worldwide annual seaweed cultivation has doubled to over 35 million metric tons in the last decade. The soy industry has shown that with biotechnology for farming, scaling can be possible and even lucrative. 

From the late 1990s to 2010s, the United States went from producing 2.5 billion to more than four billion bushels of soy annually. As conquerors of the plant-based food industry and a crucial element in biodiesel, soybeans have become a cornerstone of global agriculture. 

For seaweed to follow soy’s economic path, much more biomass would be  required. However, marine aquaculture in the United States operates within one of the most complex regulatory environments in the world, starting with the fisheries division of the federal National Oceanic and Atmospheric Administration, which seeks to ensure that aquaculture operations meet a host of federal, state, and local statutes designed to sustain healthy oceans.

A thicket of government regulations hampers coastal aquaculture

There’s a saying in the aquaculture industry: “Permitting an oyster farm is like permitting a nuclear power plant.”

Operating along California’s tightly controlled coastline is the greatest obstacle facing the state’s aquaculturists.

As Andrea Wasilew of NOAA Fisheries explained, “Navigating the permitting process is costly and time-consuming, depending on the project’s complexity. Each permit is different depending on the state, the type of farm, the scale and nature of the farm, and the local environment.” 

Federal permitting agencies do not charge fees for processing permit applications. But gathering the necessary information to support a permit application can be expensive. Depending on the proposed farm’s jurisdictional waters, NOAA requires a coordinated environmental review by two or more federal agencies. The funding for these reviews comes from the applicant’s pocket. At the start of this decade, the average regulatory cost for shellfish farms in California was $240,000 per farm.

In the current regulatory framework, aquaculture is classified with oil, gas, and other energy projects under the “offshore infrastructure” umbrella. Small, mom-and-pop farms undergo the same environmental reviews as big energy projects. 

A seaweed farm that operates in federal waters – which is nearly any offshore farm – must also comply with regulations from the U.S. Coast Guard, the U.S. Navy, and a 13-year-old defense agency set up to handle alternative energy projects. The Military Aviation and Installation Assurance Siting Clearinghouse seeks to understand environmental impacts and evaluate mitigation strategies, and shares project proposals with any military agency that offshore operations could impact. 

There’s a saying in the aquaculture industry: “Permitting an oyster farm is like permitting a nuclear power plant.”

“When costly environmental reviews are part of a seaweed entrepreneur’s calculations, the numbers don’t pencil out, and aquaculture turns into a bad investment,” Gardner said. “It’s fine for a power plant to do a study because they’re going to make millions, if not billions, of dollars. When you ask a seaweed farmer to do the same study, it costs the same amount of money. The difference is that they can’t reasonably make that money back.” 

To avoid red tape, some entrepreneurs get creative

For now, aquaculture industrialists can navigate permitting in unique ways – such as a land-based aquaculture facility that short-circuits the offshore permitting complication. 

For now, aquaculture industrialists can navigate permitting in unique ways. Moss Landing Marine Laboratories operates a land-based aquaculture facility that short-circuits the offshore permitting complication. However, land-based aquaculture involves piping saltwater upshore, which is also expensive infrastructure and requires its own permitting. Most California farms using a land-based approach utilize existing pipe systems. Monterey Bay Seaweeds, a restaurant-grade seaweed farm operating out of the Moss Landing facility, uses the Moss Landing lab’s same pipe infrastructure.

A different way to sidestep permitting requirements is to keep a farm in motion. As Cindy Wilcox, of  Marine BioEnergy, described its distinctive strategy, “the open-ocean farms under development… are not anchored to the ocean bottom, but instead are towed well offshore by inexpensive unmanned drone submarines.”

“This allows them to avoid the regulatory framework that applies to anchored farms, where they might interfere with ship traffic, recreation, marine protected areas, etc.”

The drone-towed longline farms would span a couple of acres and, using energy from solar panels, travel to a new harvesting location every few months. 

Sway, a California-based company designing bioplastics using thermoplastic seaweed (TPC) resin, sources seaweed biomass internationally – from nearly 40 countries altogether.

While there are creative approaches to tackling the current regulatory system, each presents daunting challenges to the enterprising and fiscally-minded farmer. When asked how to best address the permitting problem, Gardner said, “The most impactful thing we could do here in California to get more aquaculture going is to invest more in aquaculture parks.” That’s precisely what the Port of San Diego has set out to do. 

San Diego’s port spawns an offshore aquaculture incubator 

To shield new aquaculture businesses from the gauntlet of regulatory hurdles, the Port of San Diego created ‘Blue Tech Bay’. Their strategy relies on conducting coordinated environmental reviews in advance over 34 miles of waterfront, giving blue economy pilot projects a space to experiment.

With permitting taken care of, the Port of San Diego’s Blue Economy Incubator can focus on building a portfolio of ocean-based businesses, including seaweed aquaculture farms.

By streamlining the environmental review process, the Port of San Diego, managed by the San Diego Unified Port District, has found common ground with the United States Navy. The Port manages 34 miles of waterfront around San Diego Bay, but federal agencies, including the Department of Defense, manage the vast majority of Southern California coastline. The Port and the Navy communicate daily on what they call “maritime domain awareness”—the collection and sharing of environmental information.

Paula Sylvia, the Program Director at the Port’s Blue Tech Bay operation, says their idea is “to do this environmental review programmatically at several locations, with several different species and gear types that are commonly used, to create a more enabling environment for businesses.” With permitting taken care of, the Port’s Blue Economy Incubator can focus on building a portfolio of ocean-based businesses, including seaweed aquaculture farms.

The Port has several active pilot projects, including Sunken Seaweed, a start-up demonstrating the feasibility of seaweed aquaculture in San Diego Bay. This quarter-acre farm is about 25 feet deep and might generate 100 pounds of seaweed biomass per week per line. Other places on the California coast have the potential to support aquaculture projects in the same way that San Diego does. 

NOAA is working to support more efficient permitting by combing coastal datasets for protected species habitat, recreational fishing areas, and distance from ports along the California coast. Opportunity areas (areas appropriate for commercial aquaculture) like the Humboldt Bay Harbor District are experimenting with pre-permitting exercises. The Ventura Harbor District recently published a detailed environmental impact statement for aquaculture in federal waters off the Ventura Coast. Until offshore permitting agencies identify aquaculture as a unique enterprise, independent from offshore energy, Port and Harbor districts are currently the most effective way to promote the industry.

Capital has been scarce for American aquaculture, but new funding sources are surfacing

In other states across the Pacific Northwest with a less stringent regulatory process, including Washington and Alaska, funding is the most immediate hurdle. 

Why hasn’t American aquaculture taken off? As Dr. Sergey Nuzhdin, professor of Biological Sciences at the University of Southern California’s Dornsife College, says, “it’s a little bit of a chicken and the egg problem.” Aquaculture projects need angel investment to begin scaling, but donations are hard to come by without years of demonstrated profits from successful applications — uses of seaweed in ethanol, bioplastics or cattle fodder. 

In January 2024, The U.S. Department of Energy (DOE)’s  Water Power Technologies Office (WPTO) and Wind Energy Technologies Office (WETO) released a multimillion-dollar funding program for marine energy and offshore projects. This opportunity included up to $1.5 million to find and build on synergies between offshore wind/ marine energy and aquaculture development. 

To make kelp competitive, the industry needs national attention and, ideally, significant public and private investment.

In late August, Nuzdin noted, a delegation from Korea arrived and offered to sign a bilateral agreement with the U.S. in which both countries would commit $30 million to aquaculture technology development. For Nuzdin, “the problem is that, while $60 or $70 million sounds like a big amount… between the U.S. government and private companies, humanity spends about $200 million for the improvement of corn each year.”

To make kelp competitive, the industry needs national attention and, ideally, significant public and private investment. Whether we’re talking about a fight to streamline permitting or for investment, Gardner said, “aquaculture is struggling from people not being familiar with it… a lot of this could be addressed with aquaculture literacy, and making sure people understand what this would look like.”

 

 

Edited by Felicity Barringer and Geoff McGhee.