Study Finds Seaweed Could Reduce Methane Emissions from Livestock 

By: Sydney Sheffield 

With the 2021 United Nations Climate Change Conference (COP26) ending last month, scientists and politicians are looking for ways to achieve the promised reduction of agricultural methane outputs from ruminant livestock by 30% by 2030. Promising research is being performed at the Institute for Global Food Security (IGFS) at Queen’s University Belfast, feeding seaweed to farm animals. The technique is said to reduce methane by at least 30%.

“The science is there. It’s simply a matter of providing the necessary data and then implementing it,” said Sharon Huws, IGFS study lead. “Using seaweed is a natural, sustainable way of reducing emissions and has great potential to be scaled up. There is no reason why we can’t be farming seaweed – this would also protect the biodiversity of our shorelines. If UK farmers are to meet a zero-carbon model, we really need to start putting this kind of research into practice. I hope IGFS and AFBI (Agrifood and Biosciences Institute in Northern Ireland) research can soon provide the necessary data and reassurance for governments to take forward.” 

As Huws mentioned, IGFS has partnered with AFBI on a three-year project with UK-based supermarket Morrisons and its network of beef farmers. Morrisons has funded the project to find out how effective feeding cows seaweed from the Irish and British coasts will be in cutting emissions of greenhouse gases. Previous research in the United States found that replacing 3% of a cow’s diet with seaweed reduced methane emissions by 82%. Unfortunately, the type of seaweed used in these studies, Asparagopsis Taxiformis, contains bromoform, said to damage the ozone. The seaweed used in the IGFS studies does not contain bromoform and is rich in antibacterial compounds that could benefit overall animal health as well. 

To supply the seaweed for the study, Morrisons supermarket plans to work with its fisherman. The seaweed would then be turned into a supplement fed to the cattle. As well as assessing methane emissions of the beef and dairy cattle, these projects will measure the nutritional value of an assortment of homegrown seaweeds, their effects on animal productivity, and meat quality.

Morrisons plans to be supplied by net-zero carbon British farms by 2030. Sophie Throup, Head of Agriculture at Morrisons said “As British farming's biggest customer, we’re very mindful of our role in supporting and inspiring the farmers we work with to help them achieve goals in sustainable farming. By supporting this research at Queen’s and AFBI, we are trialing this natural approach to reducing environmental emissions and improving the quality of beef products.”