When Michael Doall was a teenager, he hated seaweed, and so did everybody else he knew on Long Island. It was an icky nuisance that brushed against your legs at the beach, fouled your fishing hook and got tangled around the propeller of your boat. Only later, as a marine scientist and oyster farmer, did he develop a love for sugar kelp, a disappearing native species that is one of the most useful seaweeds. Now he is on a mission to bring it back to the waters of New York.
He grew up on, and in the waters of, the South Shore of Long Island with a mother who considered a beautiful day a fine excuse to take him to the beach instead of school. He helped his family with an ambitious home garden in Massapequa Park and got a master’s degree in marine environmental science before becoming a shellfish specialist at the School of Marine and Atmospheric Sciences at Stony Brook University.
From there, his passions steered him into sustainable aquaculture and oyster farming, which began as a side gig to his academic pursuits. Seaweed farming is a kind of happy accident. “I love being on the water, and I like to grow things that help the environment,” he said. “Kelp farming lets me do both.”
Sugar kelp has become the seaweed of choice for New York aquaculture, though it is still in an experimental phase. In addition to being a native plant and a tasty vegetable, it cleans the oceans, capturing carbon and nitrogen from the water and helping to prevent ocean acidification and harmful algae blooms. Every acre of kelp planted removes nitrogen (a pollutant from human waste) from the water at 10 times the rate of the nitrogen-reducing septic systems now mandated for new homes in all of Suffolk County. Farming kelp doesn’t interfere with recreation because its growing season begins in December and ends with a dramatic burst of growth in May, just in time for it to be harvested and out of the water ahead of boating season.
Last December, Gov. Kathy Hochul signed legislation permitting kelp farming in Suffolk County. The measure opened 110,000 acres of Peconic Estuary shellfish leases for seaweed farming. Proponents called it the Kelp Bill.
“New York has used this new law to make real progress toward cleaning our waterways and creating economic opportunities for local farmers,” Leo Rosales, a spokesman for the governor, wrote in an email. He added that the state was working with research groups, local governments and the industry to develop infrastructure for harvesting and transporting kelp for the good of the market, the environment and area economies.
Mr. Doall unloading kelp harvested from the Great Gun oyster farm in East Moriches, N.Y.Credit…Johnny Milano for The New York Times
The big problem: Few farmers have figured out how to raise kelp successfully in New York. As of the end of this year’s growing season in May, with fall planting time around the corner, the New York Department of Environmental Conservation had not issued a single kelp aquaculture permit. So far, only two commercial farmers have even applied.
But Mr. Doall is confident he can adapt his techniques to almost any farm. “Every farm has its own personality,” he said. “Some are in deep water, some in shallow; some farmers think things out, some power it out. They all work.”
Despite the aspirations behind the Kelp Bill, New York coastal waters are not an ideal fit for traditional kelp-growing practices. Mr. Doall first got interested in kelp as a way to diversify his oyster farming; he needed a winter crop that would grow alongside his oysters, as farmers in Maine and Connecticut had discovered. But he learned that all kelp aquaculture in the United States takes place in deep water and involves 10-foot-long tendrils that hang from lines suspended underwater, swaying freely in the ocean. These conditions do not exist in the knee-deep waters of a Long Island oyster farm.
But Mr. Doall had an idea. “No one had really tried to grow in shallow water,” he said. “I like a challenge.”
In 2018, working with a grant from the New York Farm Viability Institute, Mr. Doall devised a simple staked line method to grow kelp in a few feet of water without the expensive anchors traditionally required for seaweed. He didn’t even need a boat. He tested the new method at Paul McCormick’s Great Gun oyster farm in Moriches Bay, off the Hamptons.
Mr. McCormick and Mr. Doall attended Massapequa High School in the 1980s, unaware of each other’s existence; it was oyster farming that brought them together years later. The two defied the experts, who said it was impossible to grow kelp in shallow water. They ended up producing between four and nine pounds of kelp for every foot of line they planted four years in a row — more than any other farm in New York, Mr. Doall claims, a real seaweed haul.
“Mike Doall invented shallow-water kelp farming,” said Bren Smith, a founder of GreenWave, a Connecticut-based organization that first trained Mr. Doall to farm kelp. Now Mr. Doall is a master farmer, advising, troubleshooting and willing to get wet, eager to help fledgling kelp farmers.
Word of the kelp guru spread. Buoy coming loose? He can tie a truck-hitch or a bowline and knows which knot will work. Seed thread unraveling? He’ll whip out a fid and splice it back into position — barehanded, in fact, as he did setting a new kelp line for an oyster farm in Noyack Bay one cold morning last winter.
In the four years since Mr. Doall started growing kelp, he has devised techniques for every sort of New York aquatic environment: from the fast-flowing, murky East River to the shallow, sandy bottom of Moriches Bay to the deep, pristine waters of the Peconic Estuary. He has offered advice and planted on more than 15 commercial sites — all considered experimental, as state regulators are still working out health and safety regulations for farming seaweed.
If New York seaweed aquaculture takes off, it will be in large part thanks to Mr. Doall’s ability to show other farmers how to grow where no one has grown before.
Seaweed aquaculture is barely a blip in the U.S. economy, compared with Asia, where most of the world’s kelp is grown. In the United States, seaweed is cultivated mostly in Alaska and New England, but in spite of New York’s extensive coastline and proximity to a city with enthusiastic kelp eaters, the state has been slow to develop the industry.
Harvests at the Peconic Estuary sites opened by the Kelp Bill have been a bust so far: The kelp was anemic, with pale, stunted leaves or no growth at all. The planting may have occurred too late, Mr. Doall said, but he suspects another possible explanation: Maybe the waters are too clean. Pollutants like nitrogen tend to be low in those sites, leaving kelp with few nutrients to fuel its growth.
Karen Rivara, who had kelp lines on her Peconic Bay oyster farm for the first time this year, pointed out that kelp’s ability to remove toxins from the water was a big part of why she planted. “I am not sure how commercially viable kelp is,” she said, “but I am more interested in the environmental benefits anyway.”
Fertilizer, cosmetics and fuel are all established uses for kelp, but kelp for food brings the best price, and also the best chance to make seaweed economically viable in New York. One of the newest kelp converts banking on its commercial future is Sue Wicks, the former W.N.B.A. Hall of Fame basketball player. She raises oysters in a shallow-water farm a short wade away from Mr. McCormick’s and is in her second year of raising kelp.
The first harvest was a bust, but last month Ms. Wicks harvested hundreds of pounds of sugar kelp. Her yield is being turned into kelp purées, pickles and seasonings produced by the East End Food Institute and Cornell College of Agriculture and Life Sciences, which are meant to inspire chefs and food manufacturers to find new ways to use kelp. As part of a project supported by the Moore Family Charitable Foundation, which backs conservation causes, they are not yet for sale.
“In a few years. we are all going to be considered an overnight success,” Ms. Wicks said. “I want to be part of the future and what sort of food we will eat. And I get to do it in the bay I grew up on, where my father grew up and my grandfather and my grandmother. Even if I’m just tying knots on a line with sugar kelp, I’m doing something positive.”
Shanjana Mahmud, who grows kelp with the Newtown Creek Alliance in Brooklyn, is ready to join the community. Her interest in kelp sprang from her enthusiasm for eating it, along with her interest in kelp’s environmental benefits.
Mr. Doall advised her to start by learning oyster farming, which she did on a shallow-water farm. Then she followed Mr. Doall’s example by planting kelp where no one thought it would grow: in Newtown Creek, a Superfund site and one of the most toxic waterways in the United States. Of course, the kelp from Newtown Creek would not be edible; like all New York seaweed at the moment, the kelp she grew there was experimental.
But she is now applying for an aquaculture lease near Moriches Bay, where she hopes to raise kelp for food. “I’m not from the water, or boat life,” Ms. Mahmud said. “Kelp farming seemed doable.”