Good News for Kelp

Pictured Above: Project co-leader Michael Doall (left) and Stony Brook University boat captain Brian Gagliardi harvesting a kelp line out of Southold Bay. | Gobler Lab photo

There’s great news this summer about a winter crop that could play a big role in boosting the health of our estuaries.

Researchers at the Gobler Laboratory at Stony Brook University’s School of Marine and Atmospheric Sciences (SoMAS) spent this past winter working with five local oyster farmers on a pilot project to learn whether sugar kelp will grow in local waters in the off-season, in anticipation of state enabling legislation that will allow kelp to be grown on Suffolk County aquaculture lease sites throughout Peconic Bay and Gardiners Bay. 

The results have proven promising, building on stellar success in the winter of 2019 growing sugar kelp at oyster farm sites in Moriches Bay and the Great South Bay.

To the researchers’ surprise, sugar kelp has proven to grow best in shallow waters, sometimes just a couple feet in depth, where they’ve seen 12-foot strands of kelp grow in just one to two feet of water, said Dr. Christopher Gobler at a May 27 press conference announcing the findings.

Dr. Gobler added that researchers have found growing sugar kelp is an excellent way to extract nitrogen from surface waters, and that the greater the nitrogen content in the water where it is grown, the more nitrogen it will remove.

“This means you can put it exactly where you want it,” said Dr. Gobler, whose work has long centered on harmful algae blooms that are fueled by excess nitrogen in local bays.

While there’s been much recent work being done to upgrade septic systems surrounding East End estuaries — those septic systems have proven to be the culprit for much of the excess nitrogen here — Dr. Gobler said this new research proves there’s another tool at our disposal to remove nitrogen from the water more quickly than upgrading all the septic systems surrounding bays.

“In January through May, on a one-acre oyster farm, you can grown 70,000 pounds of kelp, which represents hundreds of pounds of nitrogen,” said Dr. Gobler. “That’s the equivalent of 20 septic systems.”

Dr. Gobler also announced the beginning of a new state Nitrogen Credit Program, which is designed to offer oyster farmers $100 for every pound of nitrogen they remove from the water by growing kelp.

He said he envisions the program will, in the future, allow residents and businesses that want to become “nitrogen-neutral” a chance to pay for these credits, much the same way carbon credits are now sold to people who want to play a role in removing carbon dioxide from the atmosphere to protect the planet from climate change.

While there is currently a small market for kelp as a food source, American palates have not yet quite warmed up to kelp as a food. But the tougher parts of a kelp plant, toward the beginning of the strand, can also be turned into a fertilizer that Dr. Gobler says has the same nitrogen and phosphorous content as MiracleGro.

“We need to scale this up and make it commercially viable and available,” said Dr. Gobler. “We won’t need to be importing synthetic fertilizers onto Long Island.”

Another new finding in Dr. Gobler’s lab came this spring from research being done by Ph.D. student Peter Sylvers, who found that, when kelp is grown in the same location as the toxic algae alexandrium, the kelp helps keep alexandrium blooms in check. Alexandrium produces a neurotoxin that can be fatal to humans and is responsible for paralytic shellfish poisoning. 

“Kelp produces natural products, tannins and phenolic compounds, that are harmful to alexandrium,” said Dr. Gobler. He added that Mr. Sylvers’ research has also show that growing kelp alongside mussels in waters with alexandrium reduces the toxicity in the mussels by 50 percent.

“Now, we have a new tool for fighting harmful algae blooms,” said Dr. Gobler. “Kelp can create a halo effect on oyster farms, protecting oysters and public health.”

Now all that’s left is for New York Governor Andrew Cuomo to sign enabling legislation that has already passed both houses of the state legislature on June 8.

“I can do the science, but if it sits in a box, it’s totally useless,” said Dr. Gobler. “Kelp is affective at removing nitrogen, fighting harmful algal blooms, fighting ocean acidification and pumping oxygen into sometimes oxygen-deprived environments.”

“But kelp is only effective on a mass scale,” he said. “What we really need to move the needle and tip the balance is larger scale.”

“I think it’s very exciting,” said State Assemblyman Steve Englebright, who helped shepherd legislation drafted by South Fork State Assemblyman Fred Thiele through the State Assembly. “It gives us a sense of optimism for cleaning up our harbors and maintaining a healthful coastline. We need to employ nature.”

“Kelp will naturally remove nitrogen and protect water quality,” said Mr. Thiele. “This is a viable economic product, and the agriculture industry on the East End is just dying to get involved with this product. This bill gives us the opportunity to make our traditional industries of farming and fishing that much more viable. But it all has to be driven by science. We know we have something here that is going to promote our economy and clean up our waters. The environment and the economy here are the same thing.”

Beth Young

Beth Young built her first boat out of driftwood tied together with phragmites behind her family’s apartment above the old Mill Creek Inn in Southold. Nowadays, she spends most of her time kayaking, learning about shellfish, writing newspaper stories, trying to sail a Sunfish, and watching the way the bay changes from day to day. You can send her a message at

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