Is oyster aquaculture the future of sustainable food production?

November is “oyster month” in my home state of Virginia and I would be extremely remiss if I didn’t get at least one public piece in on how critical this creature can be for our global environment and coastal communities.

It struck me last week as I was enjoying a wonderful Thanksgiving dinner with my family and friends that this grungy looking bivalve may have a much larger role to play in our planetary sustainability than we might imagine. In fact, it is amazing to consider that oyster aquaculture may be the most viable form of Sustainable Food Production.

Before I get too deep into this, it may be helpful to take a step back and consider exactly what it means to be “sustainably produced” from a food perspective. There are numerous definitions floating around and I have some thoughts on the pro’s and con’s of each (I’ll save that for another post). However, for the purposes of this discussion, we can use the definition of “Sustainable Agriculture” found in the United States Code, 2006 Edition, Supplement 4, Title 7, Section 3013 from 2010. It reads:

(19) The term “sustainable agriculture” means an integrated system of plant and animal production practices having a site-specific application that will, over the long-term—

(A) satisfy human food and fiber needs;

(B) enhance environmental quality and the natural resource base upon which the agriculture economy depends;

(C) make the most efficient use of nonrenewable resources and on-farm resources and integrate, where appropriate, natural biological cycles and controls;

(D) sustain the economic viability of farm operations; and

(E) enhance the quality of life for farmers and society as a whole.

Let’s break this down a bit and see just how well oyster aquaculture fits this definition.

The definition begins by laying the ground rules that any operation claiming to be considered as “Sustainable Agriculture” must be “an integrated system of plant and animal production practices having a site-specific application”. By their very nature, oysters are sedentary animals. They certainly aren’t going to walk away and when cultivated in cages (as in most oyster aquaculture operations) we can be fairly certain that the benefits and detriments caused by their husbandry will be “site specific”. I think we have this one covered.

Section 19(A) says that we have to “satisfy human food and fiber needs” to be considered sustainable. Oysters have been consumed as human food for thousands of years as evidenced by the proliferation of ancient shell middens that can be found around the world and throughout the archeological record. In fact, as a species we’ve come up with very few uses for oysters OTHER than human food. (There has been some historical use of their shells to make building products, but that has long since ceased). With modern oyster aquaculture, the sole use is for humans consumption and so I believe we can definitively consider Section 19(A) as satisfied.

Now we get into the meat of the matter (pun intended…). Section 19(B) requires that any sustainable practice “enhance environmental quality and the natural resource base upon which the agriculture economy depends”. Oysters (wild and cultured) play a very important positive role in improving the surrounding environmental quality and aiding the natural resources upon which they depend by acting as a beneficial filter for the waters they inhabit.

As a filter feeder, the oyster will actually remove and process nitrogen, phosphorus, carbon and other contaminants from the surrounding waters. To the oyster, these are vital nutrients necessary for growth and sustenance. A large part of these nutrients are sequestered in the meat and shell of the organism, with the balance falling to the seafloor as feces and pseudofeces. As these discarded nutrients reach the benthic zone they become the nutritional inputs ~food~ for a wide variety of bottom dwelling animals and microorganism that further process up to an additional 20% the nutrients. In addition to processing additional nutrients, these organism go on to play an integral role in the marine food web, supporting a wide range of biodiversity.

If you are familiar at all with the ecological pressures that our estuaries and waterways are facing, you will recognize that nitrogen and phosphorus are considered major pollutants to our waters and need to be addressed. They enter our water ecosystems through agricultural and urban runoff (primarily) and contribute to algal blooms that ultimately lead to uninhabitable deoxygenated “dead zones” and fish kills. Not good stuff! The mighty oyster, however, remains hard at work day and night removing the nitrogen and phosphorus and using it for the production of shell and meat that is ultimately harvested and removed from the environmental system. While they are not a complete solution to the pollution issues from land based sources, they certainly play an important role and have the potential to play an even larger role (stay tuned…). In any case, their value to the environment is unquestionable and 19(B) seems to be adequately addressed.

Section 19(C) is the most subjective of the bunch and requires that a sustainable operation, “make the most efficient use of nonrenewable resources and on-farm resources and integrate, where appropriate, natural biological cycles and controls”. One of the unique things that distinguishes oyster (and shellfish) aquaculture from other forms of aquaculture is that the growers do not actively feed the organisms, a process which may introduce foreign or non-sustainably produced feed into the ecosystem. Instead, the oysters feed on the naturally occurring phytoplankton that are already present in the water column. It is only during the early stages of their life, when they are raised in a hatchery, that they are “fed”. Even then, the algae that is provided is sustainably grown onsite, in a controlled environment, with little to no waste products or pollution introduced back into the ecosystem. With that, I believe we can considered Section 19(C) satisfied.

In Section 19(D), a sustainable agricultural operation is required to “sustain the economic viability of farm operations”. Numerous studies and case studies (as well as our own internal research and client experiences) have shown that oyster aquaculture can be executed in a financially profitable manner, which will serve to support the economic vitality of the farm operations. Of course, there will always be some that struggle within the industry, but that is frequently the result of internal operational issues rather than broader market fundamentals. Currently, there is a large (and growing) market for oyster meat, both shucked and on the half shell. Section 19(D) – done!

Our last criteria, Section 19(E) necessitates that a sustainable farming operation serves to “enhance the quality of life for farmers and society as a whole”. This is an often overlooked area where oyster aquaculture really shines. There is a rich and vibrant coastal culture that has fallen under significant threat from development, environmental and economic pressures. As pollution, regulation and overfishing have reduced catch volumes, a tremendous number of waterman have found it necessary to move on to other professions, devastating the social fabric of their seaside communities. When their presence and prominence in the coastal communities has faded, the economies of these areas have become depressed and the social cohesion has suffered.

Oyster aquaculture has the opportunity to provide a significant family wage and help to bring back and create rewarding jobs for the waterman. Aquaculture related activities occur on the land and water and bring a wealth of positive economic impacts and opportunities to the coastal communities. In addition to preserving their charm and character, oyster aquaculture can provide an avenue for seaside communities to remain economically and culturally tied to the marine environment. The importance of this cannot be understated.

While the definition of “sustainable agriculture” provided in the United States Code is but one of the myriad definitions that is out there, it is one of the better ones. As we have shown, the practice of growing the mighty oyster in a controlled manner goes well beyond the stated definition and could quite possibly be the penultimate source of sustainable food production. Some might argue that’s taking it a little too far, but I have yet to see another form of food production that checks the requirements as completely and thoroughly as the practice of oyster aquaculture.

I am not alone in this. In fact, cultured shellfish are one of the few forms of marine aquaculture that have been recognized by the Monterey Bay Aquarium’s Seafood Watch, the Audubon Society and Eco-Fish for their ecological stewardship. In most cases, the practice of oyster aquaculture meets the National Organic Standard’s Board criteria for “organic” aquaculture. Maybe we’ll examine these criteria in more detail in a future post.

In the meantime, go support your local waterman, coastal community and planet by eating more oysters!

Moreland Advisors, Inc. is always looking for new tools, practices and capital strategies to accelerate the sustainable production of our global food supply. If you have any ideas you’d like to discuss or pursue, please don’t hesitate to contact Brad Rodgers at