Choose an Oyster Po’boy for the Planet
If every American swapped out 1 out of every 10 burgers they ate for one oyster po’boy, the greenhouse gas savings would be equivalent to having 10.8 million fewer cars on the road. This is according to a study by researchers at Boston University and the University of Wales (Canada), which was published by the American Chemical Society in 2019¹. These scientists monitored every aspect of an oyster farm over the course of seven years to determine its impact on climate change. The result is shocking: it takes over a hundred times more greenhouse gases to produce a pound of beef than a pound of oyster meat.
Aside from the shells and the horns, what makes cattle and oysters so different? We can liken the cattle to my toddler: much energy is put into preparing her food… and also in dealing with her waste. On the other hand, oysters are low-maintenance like the ultimate house guest, and actually leave the environment in better shape than they found it.
Most cattle are not raised in idyllic pastures. Instead, they are raised in cramped factory farms on diets of corn, causing immense greenhouse gas emissions.
One large advantage of farming oysters is that they don’t need to be fed by humans. The farming process consists of leaving oysters in coastal waters where they can ‘graze’ on algae that naturally grow there. Most coastlines actually suffer from an overabundance of algae, largely caused by nutrient pollution coming from farms on land (such as cow manure).
During the 2–3 years that it takes to grow oysters to a marketable size, farmers tend these ‘crops’ occasionally to keep the oyster cages clear of debris. Unlike other farm-raised foods, oysters are biologically designed to thrive in crowded conditions. The presence of farmed oysters can also benefit the wild populations of oysters and other fish that grow near the farms.
Chances are that you live closer to a potential source for oysters than to a cattle farm. Most of the world’s population lives along the coasts, and oysters have historically grown along almost every coastline. Pandemic-driven supply chain disruptions have underscored the importance of locally-sourced products.
You can feel good about the decision to order a platter of oysters for environmental reasons, as well as the myriad of health benefits they offer. However, your wallet may not share these good feelings. Despite being an oyster scientist who is well acquainted with their benefits, I still mostly reserve oysters for special occasions. This is especially true in the current era of skyrocketing food prices, when it is hard enough to afford basic groceries.
Once, oysters were enjoyed by the rich and poor alike. While food costs have gone down for most Americans in recent history, foods like oysters have become prohibitively expensive. To get oysters back on the dinner table of the average American, we must address an economic problem: why are oysters so expensive?
The better question may be: why are other sources of meat so cheap? Federal subsidies — in the form of direct handouts to producers of dairy, beef, and other meats — keep prices artificially low². In preparation for the next big farm bill on the horizon for 2023, legislators have already begun shaping the agenda for U.S. agriculture. Instead of the usual “pork” that gets packed into the farm bill, let’s consider underwriting food production that is better for the planet. The current moment of supply chain disruption and price inflation may provide an opportunity to re-think our spending priorities.
Must we swear off cheeseburgers forever? Substituting seaweed for corn as just 2% of the diet for cattle can reduce greenhouse gasses from cattle flatulence by up to 99%³. This method is already being used on farms in Ireland⁴. American companies such as Greenwave have demonstrated that seaweed and oysters can be happily raised together. You might even enjoy adding seaweed to your own diet: “dulse” — a seaweed that I like to describe as the ‘bacon-of-the-sea’ — makes for a great burger topping.
Rather than keeping the prices of unsustainable foods artificially low, the federal government should redirect agricultural subsidies to make highly sustainable options — like oysters — accessible to all Americans.
References:
1. Ray, N. E., Maguire, T. J., Al-Haj, A. N., Henning, M. C. & Fulweiler, R. W. Low Greenhouse Gas Emissions from Oyster Aquaculture. Environ. Sci. Technol. 53, 9118–9127 (2019).
2. Simon, D. R. Meatonomics: How the Rigged Economics of Meat and Dairy Make You Consume Too Much — and How to Eat Better, Live Longer, and Spend Smarter. (Conari Press, 2013).
3. Machado, L. et al. Dose-response effects of Asparagopsis taxiformis and Oedogonium sp. on in vitro fermentation and methane production. J. Appl. Phycol. 28, 1443–1452 (2016).
4. O’Brien, T. Seaweed shown to reduce 99% methane from cattle. The Irish Times https://www.irishtimes.com/news/ireland/irish-news/seaweed-shown-to-reduce-99-methane-from-cattle-1.3156975.
Heidi Yeh is a doctoral candidate in Oceanography at Rutgers University. She studies the oyster microbiome using molecular methods and strives to communicate science through food.
