Spend time talking to Charles Yarish and Paul Dobbins, and you’ll start to believe seaweed farming could be the answer to some of the world’s most intractable problems.
For starters, it could provide a highly nutritious, sustainable food source to a hungry planet; it could be transformed into biofuel that removes heat-trapping carbon dioxide even as it cleans offshore waters of pollutants; and it could create environmentally friendly economic opportunities for coastal communities.
Cultivation of this “virtuous vegetable,” as Dobbins has dubbed it, is a multimillion dollar worldwide industry, supplying key ingredients for medicines, cosmetics, fertilizers and food products ranging from sushi wrappers to ice cream thickeners.
Dobbins is president of Ocean Approved, a year-old kelp farming company that works in Casco Bay, Maine, and sells frozen kelp to restaurants and speciality food stores, growing the sinuous green ribbons in about 8 acres of offshore beds supplemented with plots tended by local shellfishermen and lobstermen.
“We sold a very successful mussel farming business to start this, because we saw a tremendous opportunity with a tremendous product,” Dobbins said.
It is now the only commercial seaweed grower based in the United States (most of the world’s cultivation now takes place in Asia). But if Yarish, the University of Connecticut professor who helped Ocean Approved get started, is right, seaweed farming has potential for major domestic expansion. He’s put a heaping measure of enthusiasm and research skills — both his own and that of UConn colleagues in the marine sciences, engineering and business departments — toward making that happen.
Pollution filters
“These are my babies,” said Yarish last week, smiling as he peered into a 13-liter jar of juvenile gracilaria plants, bubbling in seawater he trucks from UConn’s Avery Point campus in Groton to his lab at UConn’s Stamford campus. The waters in the eastern Long Island Sound, he explained, are cleaner than in the western Sound, and therefore better for the gracilaria, kelp and the other seaweed types growing in his lab. His mature seaweed plants, however, are thriving in a research plot about a half-mile offshore from Bridgeport harbor.
His down-coastal connections to Avery Point also reach the labs of two marine sciences professors based there, Senjie Lin and Jamie Vaudrey. Vaudrey is studying Long Island Sound embayments that could benefit from the pollution filtering functions of seaweed farming, while Lin’s work entails DNA and gene structure analysis to help identify the best seaweed strains for cultivation for particular areas and purposes.
Connecticut Sea Grant, also at Avery Point, has funded Yarish’s research for several years, most recently with a grant that supported the first crop of cultivated kelp harvested from the Sound last month. But Sea Grant, a federally funded program to foster coastal research, outreach and education, is now moving from behind-the-scenes financial support into promotion of seaweed farming, said Tessa Getchis, associate extension educator at Sea Grant.
Sea Grant is overseeing the preparation of an instructional manual about seaweed farming, and doing outreach to potential new seaweed growers, she said. Seaweed farming could be a means of diversifying the Long Island Sound aquaculture industry, offering shellfishermen and lobstermen a way to supplement their incomes by using the same boats and marine knowledge they possess.
“We just met with some shellfishermen to determine what their level of interest is,” Getchis said. “I don’t know that there’s room in Long Island Sound for many large-scale operations, but I definitely see potential for some smaller scale ones. There’s just so much demand now for local and sustainable food sources.”
Permits are being sought for a startup commercial seaweed farm in central Long Island Sound, and she also has had inquiries from potential growers in Rhode Island and Massachusetts.
From the Bronx to the Cape
At the Stamford UConn campus, business professor Tim Dowling is assigning his students to develop plans to maximize the economic viability of seaweed farming.
“I tell my students, ‘You’ve got one ton of seaweed, what are you going to do with it?’” Dowling, who specializes in sustainable industries, said. “We’re working on optimizing the revenue streams, so there’s no waste.”
Possibilities include selling the premium parts of the harvest for human food, and scraps for products ranging from animal feed to nutrition supplements.
Deriving income for seaweed farmers through the state’s nitrogen trading program, which would assign a dollar value to the amount of nitrogen a seaweed plot absorbs from the waters, is also being explored, Dowling said.
Yarish, who has been involved in seaweed research for decades, is eager to do what he can to ensure that this budding interest in seaweed farming blossoms both locally and beyond. He readily shares his expertise as well as seed stock from his lab. In addition to the work in his own plots and lab and with Ocean Approved, he also has worked in the Bronx River on a project that pairs shellfish farming with seaweed-growing as a means of cleaning an urban waterway.
He also is supplying seaweed stock for a project in Waquoit Bay in Cape Cod and has made overtures to two culinary institutes about preparing dishes with locally grown seaweed. In addition, he has partnered with the Bridgeport Regional Aquaculture School and Technology Education Center on Long Island Sound to involve high school students in seaweed cultivation.
Easy to grow
Grown in buoyed plots off anchored lines that can extend a mile or more and are hauled out at harvest time, the seaweed grown in the Sound, Yarish said, must be fast growing and adaptable to wide ranges in water temperatures and other conditions.
“In Long Island Sound,” Yarish explained, “we’re doing very precise work, studying the best depth and density (for the plants) and frequency of harvest.”
The plants are analyzed periodically to assess their nutrient uptake, growth rates and other properties. After harvest, the seaweed is dried and packaged. Most of the world’s edible seaweed is sold as a dried product.
As a crop, seaweed is relatively easy to grow, said Dobbins, the Ocean Approved president. It doesn’t require weeding or watering, so isn’t as labor intensive as some land crops, and grows in relatively shallow, near-shore waters where sunlight can penetrate to the plants. One of the main issues that faces seaweed farmers, he said, is working out the bureaucratic issues involving use of marine property and permitting with regulators from the state and the U.S. Army Corps of Engineers.
Yarish’s plot is the only permitted seaweed farming site in Long Island Sound. But Kristen Bellantuono, environmental analyst with the state Department of Environmental Protection’s Office of Long Island Sound Programs, said her office is reviewing one permit application from a new grower, and is prepared for more. The key issues considered in granting a new permit, she said, are whether the lines and buoys cordoning off the seaweed plot would interfere with established lanes for recreational and commercial boating and fishing.
“We don’t want to create any user or navigational conflicts,” she said.
Yarish believes Connecticut may need to establish policies to work these issues out systematically rather than on a case-by-case basis, such as by enacting marine spatial planning — something like zoning for the sea — that would designate particular areas as suitable for specific uses such as seaweed farming. He also noted that some types of commercially valuable seaweed, such as kelp, are grown and harvested from late fall through early spring, when recreational boating and fishing traffic is at its ebb.
“Because I’ve been around the Sound for 35 years, I know all the sites from the far east to the far west,” he said. “We have a huge number of sites that have potential (for seaweed cultivation). It’s as far as the coastal managers would like to see it. The idea is to do this in Long Island Sound in a way that makes sense for Connecticut and New York.”

© 2012 The Day (New London, Conn.)
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