Recent technological discoveries give us hope for a green future. We have affordable, relatively cheap and efficient solar energy, and even robots that might be able to remove plastic from the oceans. You might then think that it shouldn’t be too hard to do something to make cows spew methane into our atmosphere. The livestock industry, its allies in the scientific community and its partner companies like Burger King aspire to carbon neutral cows. And recently a lot of them are hanging on to seaweed like the hamburger saving grace.
This year the farms of the world will come out about 72 million tonnes of beef. Beef production accounts for around 6 percent of all greenhouse gas emissions, which is inconsistent with sustaining global warming within reasonable limits of 1.5 or 2 C. Our global appetite is rapidly turning into a huge environmental problem. But could a quick fix feed the cattle in the form Asparagopsis taxiformis, a red algae from the tropical oceans, does it really offer redemption to climate-conscious burger lovers?
In recent studies, adding algae to livestock feed has shown promise in removing bovine methane. Some tests have resulted in reductions of 80% apparently revolutionary. Maybe instead of going vegan or adopting plant-based burgers, we can just feed the cows seaweed and keep going. Or so the thought goes. This glimmer of hope has enabled algae the headlines, startups to win million dollars in funding, and fast food chains to say that their beef turns green. But do all of these claims really stand up to scrutiny? Unfortunately no.
The truth is, the benefits of seaweed are probably much more limited, both in their ability to reduce cows’ methane emissions and in their potential to scale up the problem. Many claims of the technology’s promise are based on small-scale testing – to have a significant impact, we’ll need to find a way to supply algae to most of the 1.5 billion cows in the world, including 100 million. in the United States alone. .
Plus, feeding livestock algae is only really practical where it’s least needed: on feedlots. This is where most of the cattle are found crowded in the last months of their life from 1.5 to 2 years to gain weight rapidly before slaughter. There, algae feed additives can be mixed with grain and soybeans from cows. But on the feedlots, the cattle already burp less methane—Only 11 percent of their lifetime production. This is because most of their methane comes from their gut microbes breaking down the non-digestible grass, leaves and forage that they pre-eat in pastures, not corn and soybeans from feedlots. . This means that even if the algae diets on the feedlots worked perfectly, it wouldn’t help the 89% of cow belching that occurs earlier in their life.
Unfortunately, adding algae to pasture diets where it is most needed is also not a feasible option. On pastures, it is difficult to get the cows to eat additives because they don’t like the taste red algae unless diluted in animal feed. And even if we do find ways to sneak algae somehow, there’s a good chance their gut microbes adapt and adjust, bringing the methane from their belching to high levels.
All in all, if we accept the most promising claims of algae boosters, we’re talking about an 80% reduction in methane from just 11% of all burps, or about 8.8% total reduction. Maybe a little more if we can incorporate algae into the diet of cows on pasture. And this Would only really count as a serious climate change mitigation strategy if we could find a way to change the diets of hundreds of millions of cows. This is not only a major logistical and economic challenge, it could also pose its own problems, as we would have to face the potential ecological impact large-scale seaweed farming, whether in the wild or in aquaculture operations.
And there is another problem. Although cow belching is the largest source of agricultural methane, the production of beef and dairy products involves many other climate emissions, from their manure to the fertilizer sprayed on their crops and grasses, to the transport of cattle. animals and later meat. While there may be technological solutions to all of these different emissions in a cow’s life cycle, algae is far from the silver bullet that can solve them all.