Joanna Foster 4 minute read

Searching for a seaweed to combat cow burps

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Visitors to Wolfe's Neck Center for Agriculture and the Environment in Freeport, Maine are greeted by a nearly life-sized cardboard cut-out of a cow.  

A man standing in front of a cardboard diagram of a cow
Wolfe's Neck uses teaching tools, like the Moo-na Lisa, to help educate people about agriculture. (Wolfe's Neck Center)

Fondly dubbed the Moo-na Lisa, the cow-shaped sign details all the inner workings of a dairy cow. It’s just a small part of the farm’s mission to educate the public about food systems and the impact of agriculture on the environment.  

In addition to being a working dairy farm with 40 milking cows that supply fresh milk to Stonyfield Organic, Wolfe’s Neck is a living laboratory trialing innovative farming practices that put the health of people and the planet first.  

One of these experiments tackles one of the thorniest issues surrounding dairy cows and a warming world — how to make cows burp less. Why? Cow burps contain methane, a powerful greenhouse gas with 80 times the warming power of carbon dioxide in the first twenty years after it enters the atmosphere. And the world’s roughly 1.5 billion cows burp a lot of methane.  

In collaboration with Bigelow Laboratory for Ocean Sciences, the University of New Hampshire and many other partners, Wolfe’s Neck is testing whether feeding cows local seaweeds can reduce the amount of methane they release from their stomachs.  

A farmer standing in a field with some cows giving a lecture to people surrounding
Much of the methane produced by humans comes from livestock, including cows. (Wolfe's Neck Center)

Agriculture represents nearly 40% of human-caused methane emissions, the majority of which comes from livestock including dairy cows.  

Cows produce methane in two ways: from the decomposition of their manure under certain conditions, and by what is politely known as enteric emissions — cow burps, by far the largest source. Methane emissions from manure can be drastically reduced by changing how manure is stored and treated, while changing a cow’s diet and supplementing it with feed additives that interrupt the microbial processes in a cow’s gut can dramatically slash enteric emissions.  

One such feed additive, Bovaer, recently became the first such product to be cleared for market use in the U.S. by the FDA. In studies, Bovaer can reduce methane by around 30%. Also promising are certain species of seaweed. Feed additives made with the red tropical seaweed (Asparagopsis), for example, which grows off the coast of Australia, may cut methane from belching as much as 80%. Although much more research still needs to be done to prove that it is effective and safe for both cows and people. 

A large batch of seaweed being pulled onto a boat by fishers
Seaweed could help reduce methane emissions by decreasing the BPC (belches per cow). (Atlantic Sea Farms)

Researchers at Bigelow are screening seaweed varieties native to the Gulf of Maine for methane-reducing compounds with similar efficacy. Nicole Price, who leads the research, says that so far, her team has identified about a dozen local varieties of seaweed — and dozens more single-celled microalgae — that could hold promise.   

Wolfe’s Neck and others are running field trials to measure just how effective different seaweed supplements are at reducing methane from belching bovines, while also keeping close tabs on whether the additive affects milk yield, composition or quality.  

“Feed additives could be game-changers,” explains Ben Thomas, senior policy director for climate-smart agriculture at Environmental Defense Fund. “For years, people just shook their heads and asked, ‘How do you want us to keep cows from burping?’ But now, there’s something that could really make a dent in these emissions.” 

The next trial of a promising seaweed species will take place at Wolfe’s Neck next year. While it will still probably be years before seaweed additives from Maine can be used commercially, some important progress has been made. In February, the FDA moved to modernize the review and approval process for these types of feed additives to help bring innovative solutions to market more quickly while maintaining safeguards for animal health, human health and the environment.  In addition, both the Senate and House have introduced bipartisan legislation to help farmers use enteric methane solutions, and this legislation may be included in the next farm bill. 

“Many dairy farmers already feed their herds kelp supplements as a kind of nutritional boost,” explains Alex Gulachenski, farm network manager at Wolfe’s Neck. “If we could help them switch to different seaweed species supplement with all the same health benefits, plus methane reducing properties, it would be a win-win for everyone.” 

“Farming has always involved experimentation,” Gulachenski adds. “And in a warming world, we’ll have to be more creative than ever, not just to adapt to new conditions, but to be part of the solution.” 

Hope for a warming planet

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