What is Oyster Maricutlure?
When most people think of aquaculture, they imagine an industry focused on raising salmon, tilapia, and other finfish species in ponds or cages. As a result, many people perceive aquaculture to be environmentally harmful given the reputation of these fish farming methods to pollute and to produce nutritionally inferior fish.1 What many consumers may not know, however, is that oyster marine aquaculture, or “mariculture,” is a sustainable practice that produces healthy seafood and provides a variety of ecosystem benefits. Whereas finfish aquaculture requires large amounts of feed and produces waist, oysters obtain all the food they need from the surrounding water and clean, rather than pollute, water. Additionally, oyster farms provide habitat for many important fish species.2
Mariculture in North Carolina
North Carolina has the second longest Atlantic coastline in the United States and has waters that provide the ideal physical and biological conditions for oyster growth. This has led some to proclaim that North Carolina can become the “Napa Valley of Oysters”. 3 Even with these resources, however, mariculture remains a small, growing industry and faces many challenges.
Currently, there is a need for ecological restoration and coastal economic development in North Carolina. Oyster mariculture provides a win-win solution to these coastal needs. As a result, consumers should purchase, encourage local vendors to sell, and take pride in North Carolina oysters while encouraging the General Assembly to act on recommendations provided in the Strategic Plan for Shellfish Mariculture.
Economic Need
Coastal North Carolina has long relied on marine resources to spur economic growth.4 Recently, however, both local economies and marine ecosystems have struggled. Finfish landings in the state have declined significantly from a peak value of 110 million dollars in 1981 to 31 million dollars in 2012.5 As such, limited commercial fishing opportunities and above average unemployment and poverty rates in coastal communities have sparked a pattern of migration from rural to urban areas that threatens community structure and coastal cultures.6
Ecological Need
Beyond economic need, the decline of wild oysters has had significant environmental consequences. Oyster harvests in North Carolina have declined 50-90% in the last century due to overfishing, shellfish diseases, and unsuitable water quality.7 The NC Division of Marine Fisheries reported that the 119,186 bushels landed in 2015 accounted for just a mere 15% of the 800,000 bushels landed in 1889.8 This enormous collapse is important because oysters play an essential role in maintaining water quality and providing important habitat for commercially and recreationally important fish.9
Mariculture as an Economic Remedy
Oyster mariculture can provide sustained economic growth where it is needed the most. Expanding the industry in North Carolina will create jobs, including those for displaced commercial fishermen, and could produce upwards of $100 million in economic activity annually and 1,000 coastal jobs by 2030 according to predictions based on trends in other states.10 Such hope for the industry is founded on continued, increasing demand for oysters in the United States which is currently around 33 million pounds.11 This demand has in part grown from the favorable public perception of oysters propagated by media and vendors. Accelerated press coverage has praised oysters as healthy, environmentally friendly foods, and restaurants continue to portray oysters as a unique and trendy luxury item.12
Mariculture as an Ecological Remedy
Oyster mariculture can also help compensate for the ecosystem functions wild oyster stocks formally provided. As filter feeders, oysters eat by pumping water through their bodies. This feeding process removes nutrients and suspended sediments from the water. It has been estimated that a single oyster can filter more than 50 gallons of water in a day.13 As a result, oyster farms can provide the significant filtering services formally carried out by wild populations. In addition to helping water quality, oyster farms also increase habitat for juvenile fishes and other aquatic species that helps preserve biodiversity and fill the hole left by the destruction of wild oyster reefs.14
What the State Can Do
At the beginning of this year, the North Carolina Policy Collaboratory, a research and policy center at UNC-Chapel Hill, submitted the “North Carolina Strategic Plan for Shellfish Mariculture” to the General Assembly that features a list of 21 recommendations for the state to overcome barriers to the expansion of the industry. These recommendations include statutory changes that the committee has asked the North Carolina Legislature to consider. It is important that the legislature prioritize these changes and that the recommendations are considered without being shut down by the commercial fishing lobby which has been resistant to change.
What You Can Do
On an individual consumer basis, it is important that North Carolina citizens continue to demand in-state oysters and support local farms. States such as Virginia and Connecticut continue to dominate the markets around the United States and in North Carolina even though superior growing waters exist within the state. Consumers need to recognize that instate oyster production can bring financial returns, jobs, cleaner water, and healthier ecosystems to North Carolina so that they eat instate oysters and encourage the General Assembly to act on the proposed plan.
[1] Bacher, K. (2015). Perceptions and misconceptions of aquaculture: a global overview. GLOBEFISH Research Programme; Rome, 120, I,1-35. Retrieved from https://search.proquest.com/docview/1753266986/citation/968E9E8D455B4D12PQ/1
[2] North Carolina Strategic Plan for Shellfish Mariculture. (2019, December 30). NC Policy Collaboratory. Retrieved from https://www.nccoast.org/wp-content/uploads/2019/01/NC-Strategic-Plan-for-Shellfish-Mariculture-Final-20181230.pdf
[3] North Carolina Oysters Are Local, Sustainable. (2018, August 18). Retrieved February 19, 2019, from https://www.ncfieldfamily.org/farm/north-carolina-oyster-farmers-are-shelling-it-out/
[4] North Carolina’s Ocean Economy: A First Assessment and Transitioning to a Blue Economy. (2017, January). Sea Grant North Carolina and Duke Nicholas Institute. Retrieved from https://ncseagrant.ncsu.edu/ncseagrant_docs/products/2010s/NC_Ocean_Economy_White_Paper.pdf
[5] Mclnerny, S., & Hadley, J. (2014, March). An Economic Profile Analysis of Coastal Commercial Fishing Counties in North Carolina. North Carolina Department of Environment and Natural Resources, North Carolina Division of Marine Fisheries. Retrieved from http://portal.ncdenr.org/c/document_library/get_file?p_l_id=1169848&folderId=32492807&name=DLFE-139617.pdf
[6] Lawrence, S., Beaulieu, T., Green, A., Kanabrocki, A., O’Connor, A., & Oliver, Z. (2015, January). Coastal Restoration and Community Economic Development in North Carolina. RTI International.
[7] History of Oysters in NC | North Carolina Oyster Blueprint. (n.d.). Retrieved February 19, 2019, from https://ncoysters.org/oysters/history/
[8] State of the Oyster: 2015 Progress Report. (2015). North Carolina Coastal Federation. Retrieved from https://www.nccoast.org/wp-content/uploads/2014/12/8912-NCCF-Membership-Publication.pdf
[9] Momentum Grows for Aquaculture in the United States | NOAA Fisheries. (2017, October 2). Retrieved February 19, 2019, from /leadership-message/momentum-grows-aquaculture-united-states
[10] North Carolina Strategic Plan for Shellfish Mariculture. (2019, December 30). NC Policy Collaboratory. Retrieved from https://www.nccoast.org/wp-content/uploads/2019/01/NC-Strategic-Plan-for-Shellfish-Mariculture-Final-20181230.pdf
[11] Momentum Grows for Aquaculture in the United States | NOAA Fisheries. (2017, October 2). Retrieved February 19, 2019, from /leadership-message/momentum-grows-aquaculture-united-states
[12] Sackton, J. (2018, February). Outlook for Oysters in the US Market and Beyond. Powerpoint presented at the Seafood Datasearch, Summerside, PEI. Retrieved from https://www.aquaculturepei.com/media/news_industry/news_industry31.pdf
[13] Strong, A. (2018, October 10). Oysters On The Half Shell Are Actually Saving New York’s Eroding Harbor. Retrieved February 21, 2019, from https://www.npr.org/sections/thesalt/2018/10/10/654781446/oysters-on-the-half-shell-are-actually- saving-new-yorks-eroding-harbor
[14] North Carolina Strategic Plan for Shellfish Mariculture. (2019, December 30). NC Policy Collaboratory. Retrieved from https://www.nccoast.org/wp-content/uploads/2019/01/NC-Strategic-Plan-for-Shellfish-Mariculture-Final-20181230.pdf
I agree that mariculture should be a significant focus for future economic development in coastal North Carolina, and more specifically any marine spatial planning processes that occur should examine aquaculture and its various sub-industries including oyster mariculture. The decline of the fishing industry is a complex issue with multiple roots, as you identified in your post, and any attempts to address this problem will need to consider a wide range of options. The future of offshore energy technology, the state of coastal vegetated habitats (mangroves, salt marshes, and seagrasses), the several private industries including fishing and tourism–all of these topics and several more are interconnected and present a difficult management dilemma for our government. Oyster mariculture also deserves to be in this conversation for the reasons you identified. Wild oysters are important for our coastal ecosystem and our coastal economy. I’m interested in whether it would be better to present the Strategic Plan for Shellfish Mariculture to Government Cooper or the NC General Assembly to incorporate in any long-term marine spatial planning processes.
Hey Max! I thought your blog was very topical, especially the call to action at the end for NC citizens to demand more in-state oysters. I too am hopeful that consumer demand will be able to support a growing oyster industry.
It’ll be interesting to see how support of the oyster industry shakes out on the coast. Commercial fishers may feel threatened by the growing industry, or they may be glad for the increase in nursery habitat. Waterfront property owners and recreational boaters may have complaints regarding the aesthetic and navigable value of the near-shore aquaculture facilities, or they may be excited about the prospect of more local oysters. Those dichotomies may dictate the future of the industry and the state policy that governs it.
I found this article really intriguing, especially because I previously thought that all marine agriculture was damaging,rather than restorative to the environment in many ways. It would be interesting to see whether a flourishing filter feeder population could buffer the effects of eutrophication in coastal North Carolina, especially after flood events that we have seen with increasing frequency in the past few years. I recall a lecture my professor for Enviro 101 gave last semester about algal blooms in Lake Erie that were devastating for its ecological systems. When zebra mussels, an invasive species, found their way into Lake Erie, their population exploded because there was not a significant amount of natural predators. The water, she said, cleared up very quickly and all of the sludgy green algae disappeared as the mussels filtered the water. That said, they were a rapidly proliferating invasive species and they outcompeted other species that occupied the same niche, until a native fish population (whose numbers declined as a result of the algal bloom) bounced back and controlled the mussels population. I wonder if this same issue of filter feeders outcompeting other species could happen if we cultivated oysters in North Carolina. Are the oysters invasive and do they have natural predators that can keep them in check if their population grows significantly?