This story was originally published by Honolulu Civil Beat.

Limu kohu is most traditionally destined for poke bowls, but the distinctive-tasting seaweed is now increasingly in demand for cattle to reduce the amount of methane they burp into the atmosphere. 

Parker Ranch cattle are among the first of Hawai’i’s livestock to be fed farmed red algae. In previous trials, the seaweed has been found to reduce the amount of methane the animals belch by an average of 77 percent, according to Kona-based business Symbrosia. 

The algae’s ability to mitigate cattle’s greenhouse gas emissions has elevated Symbrosia and Blue Ocean Barns, another limu kohu farm based in Kona, in the growing international seaweed farming industry.

Fueled by its litany of potential applications and climate change-mitigating properties, the World Bank predicts the industry could be worth almost $12 billion by 2030. And that is attracting immense public and private investment interest across the globe, including in Hawai’i. 

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The federal government awarded Symbrosia more than $2.2 million in grant funding this year, including a U.S. Department of Agriculture organic market development grant for $1.2 million late last month. 

That catalytic funding will increase the five-year-old operation’s production by 1,600 percent, Symbrosia CEO Alexia Akbay said. That means just over 6,000 cattle could be eating Seagraze, the red algae product, as part of their diet. The cap is currently 250 cattle. 

Cattle on Parker Ranch have been among the first of Hawai’i’s cattle to consume limu kohu as part of their diets. Nathan Eagle/Civil Beat/2023

With a $1 million grant from the National Science Foundation, awarded in January, it plans to streamline its currently labor-intensive production process, one that involves three stages of finicky cultivation and drying.

Blue Ocean Barns signed on with two major mainland dairies, as well as ice cream producer Ben & Jerry’s, raising $20 million. Symbrosia last year signed on with Organic Valley, the nation’s largest farmers cooperative, and Danone, the country’s largest yogurt producer. 

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The recent injection is “really the next step for us to start expanding commercially for our products, for both local producers like Parker Ranch and then some larger companies like Organic Valley,” Akbay said.

But the company does not appear to be leaving any time soon, given the growing conditions and Hawai’i’s unique climate. Symbrosia is expanding its footprint from a quarter of an acre to 15 acres and looking to increase its staff by 70 positions, Akbay said.

That’s partly because of the year-round growing climate for the seaweed farm.

“We probably harvest a little bit more frequently, ship out product more frequently, just because the seaweed grows so quickly,” Akbay said.

But now the race is on to commercialize and scale the product across the world, given how high demand might be in the future, says Jim Wyban, who developed pathogen-free shrimp which underpins the global shrimp industry.

Jim Wyban is a proponent of strengthening the local food system, particularly through fish and algae farming. David Croxford/Civil Beat/2023

Going global

Major dairy and beef producers worldwide have started expressing serious interest in methane-reducing seaweed since researchers in Australia discovered its potential. The country’s first commercial harvest was in 2022. 

Meanwhile, the Global Methane Pledge, with 155 signatory nations, specifically targets livestock because they contribute the bulk of agriculture’s emissions. And agriculture accounts for 37 percent of the world’s total methane discharged by humans.

A single cow produces between 154 to 264 pounds of methane per year. The U.S., which commands a 20 percent share of the international beef industry, has a cattle population of more than 87 million.

“They’re going after a really big problem,” Wyban, a leader in Hawai’i’s aquaculture industry, said of the seaweed companies. 

The global market for seaweed-based animal feed supplements could be worth $1.1 billion by 2030, according to the World Bank. 

There has been local interest beyond Parker Ranch, Hawai’i Cattlemen’s Council managing director Nicole Galase said. But many ranchers want to see results first, Galase said.

Symbrosia’s research with Parker Ranch is slated to last nine more months. The red seaweed has been associated with faster weight gain in cattle, more milk production, and even faster wool production in sheep. 

“We want this research and ingenuity coming up because we do want options. Ranchers are always looking for a way to improve,” Galase said. “That takes research, that takes people trying things.” 

But having a locally-grown and produced product is not going to keep more livestock in Hawai’i, where a large proportion of cattle are shipped to the mainland. The number of cattle shipped to the continental U.S. is mainly determined by how much grass Hawai’i has at any given time, a factor largely dictated by drought, Galase said. 

A valuable crop

There are several other algae-based markets, including construction materials, fertilizers, and other agricultural inputs, bioplastics, biofuels, and fabric.

Each represents an opportunity for greater environmental and economic sustainability, said Todd Low of the state Department of Agriculture.

“There’s three kinds of value to seaweed: There’s the ecosystem services, the filtering of water and benefits to the environment. There’s carbon sequestration, … then there’s this value-added processing,” Low said.

Algae already sits just behind cattle as Hawai’i’s fifth most valuable agricultural crop. It was worth $45 million in 2022. Hawai’i’s entire aquaculture sector is anticipated to reach $600 million by 2034, according to the Department of Agriculture. 

“There’s a whole world of different value-added things,” Low said. “For us, the focus on macroalgae or seaweed is the vehicle into that world.”

State lawmakers have expressed interest in aquaculture recently, though Hawaii has largely ignored fish and algae farming in the past, instead favoring land-based farming. Little has materialized from legislation introduced in recent years.

But algae has still grown as an industry, with little help.

What Symbrosia and Blue Ocean Barns have shown is that Hawai’i can compete in the aquaculture space, Low said. 

Hawaii Grown” is funded in part by grants from the Stupski Foundation, Ulupono Fund at the Hawaii Community Foundation, and the Frost Family Foundation.

Civil Beat’s coverage of climate change is supported by the Environmental Funders Group of the Hawaii Community Foundation, Marisla Fund of the Hawaii Community Foundation, and the Frost Family Foundation.