Seaweed farming supporters envision commercial, environmental benefits
April 26, 2023
To optimists, the plants that grow in the sea promise to diversify Alaska’s economy, revitalize small coastal towns struggling with undependable fisheries and help communities adapt to climate change — and even mitigate it by absorbing atmospheric carbon.
Cultivation of seaweed, largely varieties of kelp, promises to buffer against ocean acidification and coastal pollution, promoters say. Seaweed farms can produce ultra-nutritious crops to boost food security in Alaska and combat hunger everywhere, and not just for human beings.
“Kelp is good for everybody. It’s good for people. It’s good for animals,” Kirk Sparks, with Pacific Northwest Organics, a California company that sells agricultural products, said in a panel discussion at a mariculture conference held in February in Juneau, sponsored by the Alaska Sea Grant program.
But before it achieves these broad benefits, Alaska’s mariculture industry must first address significant practical issues, including an American consumer market that has yet to broadly embrace seaweed.
Seaweed farming is part of an expanding mariculture industry in Alaska that, until recently, was almost exclusively about oyster farming. Commercial seaweed production in the state has grown in volume from virtually zero in 2016 to about 650,000 wet pounds in 2022, according to the Alaska Fisheries Development Foundation.
Ambitions for seaweed cultivation and other forms of mariculture are high.
A task force established by Gov. Bill Walker and continued by Gov. Dunleavy set a goal for an Alaska industry generating $100 million a year in revenue. In contrast, the Alaska industry was worth only about $1.5 million as of last year, according to the National Oceanic and Atmospheric Administration.
Along with the lofty ambitions, there are high levels of new investment. Through the American Rescue Plan Act of 2021, the U.S. Department of Commerce last year awarded $49 million to a “mariculture cluster” of Southeast Alaska organizations for projects that include seaweed farming.
The Exxon Valdez Oil Spill Trustee Council, the federal-state panel that administers money paid by Exxon to settle government claims over the massive 1989 oil spill, has devoted nearly $32 million to mariculture research and development, focusing on the spill-affected Prince William Sound.
Other investments range from $500,000 from the U.S. Department of Agriculture for a mariculture incubator and processing facility to several million dollars appropriated by the state Legislature to the University of Alaska for mariculture research and training.
Alaska is currently a long way from being the world’s seaweed-producing capital. The global commercial industry, with an estimated value of $14 billion in 2020, is heavily dominated by Asian countries. Harvested seaweed from Asia goes into a variety of products — for industrial and agricultural use as well as well as for food.
Within the United States, producers in Maine dominate the seaweed-cultivation industry, holding 80% of the market, according to Liz MacDonald, of Maine-based Atlantic Sea Farms, who spoke at the Juneau conference.
Products coming from Maine include kelp flakes, kelp seasoning and kelp burgers. A Maine company called Rootless sells bite-sized kelp squares made in five fruity or nutty flavors and marketed as nutrient-packed superfood snacks.
While Alaska seaweed farmers are looking to Maine for practical lessons, they are also pointing to potential environmental benefits at home.
There is encouraging scientific evidence that seaweed cultivation buffers ocean acidification locally, as described in studies from various projects, including some from China, California and New York. Seaweed farming “could serve as a low-cost adaptation strategy to ocean acidification and deoxygenation and provide important refugia from ocean acidification,” said the study from China, published in 2021 in the journal Science of the Total Environment.
But does seaweed farming result in absorption of atmospheric carbon and prevention of it streaming back into the atmosphere? The answer is complicated, according to scientists. It depends on what happens to the kelp. If dead and decomposing bits are on land or in shallow waters, they would likely release carbon back into the atmosphere, scientists say.
Another environmental consideration involves wild stocks of bull kelp, one of the prime commercial species.
Stocks are so depleted in U.S. West Coast waters that an environmental group, the Center for Biological Diversity, has petitioned for an Endangered Species Act listing, which would be a first for any marine plant.
Abundance trends for wild bull kelp vary a lot by location, with numerous problems documented in California, but Alaska’s Aleutian Islands region is another trouble spot for wild bull kelp. There, a population crash among sea otters is linked to the kelp decline. Sea otters normally eat sea urchins, and without being held in check by otters, the kelp-eating urchins have been mowing down the underwater forests, according to several scientists.
While climate change, pollution and other problems are considered bigger threats, overharvesting also puts wild kelp at risk, according to the listing petition, currently under review by NOAA’s National Marine Fisheries Service.
Kelp farming, however, might help restore wild populations, according to some experts. A project in Puget Sound is investigating that possibility.
Several potential environmental downsides to seaweed farming are described in a report published in 2021 in Scotland — another part of the world where seaweed aquaculture is seen as a promising new industry. Among them, according to the report: shading that reduces sunlight needed by other organisms within the water column, possible introduction of invasive species, underwater entanglements of marine mammals and obstructions to travel in the water.
For businesses, there are plenty of economic challenges.
One is logistics. Unless companies are manufacturing specialty products, like the kelp-based salsas sold by Juneau’s Barnacle Foods, the project has to be dried. Wet plants in bulk are too heavy and too expensive to ship from Alaska.
Kelp is “a wonderful differentiating ingredient” and “really wonderful for grabbing the attention,” but not everyone is open to eating it, said Matt Kern, co-founder and co-owner of Barnacle Foods, which sells a variety of kelp sauces, condiments and other products.
“We can tell you that there’s not a tidal wave of customers knocking on doors for kelp products,” he said at the Juneau conference.
The Alaska Seafood Marketing Institute, the state agency that promotes Alaska fish, is unable to help, at least for now. State law prohibits it.
In Alaska Native culture, seaweed is a traditional food, with no such marketing outreach needed. That leads to some wariness in Indigenous communities about the proliferation of kelp farms.
Jim Smith, restoration manager for the Cordova-based Native Conservancy, expressed some of those concerns at last month’s conference.
“Be mindful of what you’re asking kelp to do for you. Be mindful of the water you’re asking your permits to occupy before you ask Indigenous people to share their knowledge,” he told the conference audience.
“It’s a lot of pressure on kelp,” he said.
The Alaska Beacon is an independent, donor-funded news organization. Alaskabeacon.com.