By Emmi Palenbaum, S.C. Sea Grant Consortium
The miles and miles of beautiful, green salt marsh along the South Carolina coast are no secret. But the impressive creatures that live within are sometimes less well-known. Introducing the Eastern Oyster, Crassostrea virginica: a magnificent symbol of Lowcountry culture and heritage, a vital foundation for ecosystem health, and a signature treat on menus across the state.
Wild oyster harvest season opens annually around the beginning of October, but we are lucky enough to enjoy delicious single oysters year-round thanks to shellfish mariculture, a practice that uses gear within leased estuarine areas to craft perfectly shaped and uniquely briny oysters. Shellfish mariculture operations harness the nutrients and tidal motion of salt marshes to feed and shape the oysters. Importantly, these farmed oysters are grown using techniques that enable them to remain submerged until harvest, lessening the chance of bacteria formation that can pose human health risks during the warmer summer months.
A beautiful aerial view of Barrier Island Oyster Company’s farm in the South Carolina lowcountry sets the scene and highlights the critical role of oysters in the salt marsh ecosystem. Photo courtesy of Will Fontaine.
South Carolina’s coastline is home to intricate waterways, including 20% of salt marshes on the East Coast. When salt and fresh water come together in the estuaries, they create an optimal natural environment for the growth of oysters, the foundation of a complex ecosystem. Check along the marsh edge: you’ll find clusters of oysters forming reefs, which stabilize the marsh from erosion and provide habitat and food to crabs, fish, and many other species. In the midst of an ever-growing tourism industry and a rising demand for fresh and local seafood, shellfish mariculture benefits the natural oyster resource, and ultimately the overall ecosystem in a variety of ways. Farmed oysters reduce reliance on the wild oyster harvest, provide shell to be planted back onto reefs for oyster recruitment, and increase water filtration.
S.C. Sea Grant has long provided technical expertise to the mariculture industry in South Carolina. Collaborative efforts among the Consortium, partnering institutions, and industry members have broadened the abilities of the industry. Julie Davis, farm manager of Lady’s Island Oyster, studied oyster mariculture, and in combination with her two decades of unique experience, brought expertise and new knowledge to South Carolina. With her background as a scientist, Davis emphasizes that, at its core, “aquaculture business is the practical application of science to improve seafood production.” This translation of science has prompted the healthy expansion of the industry through advancements of gear technology and regulation, with many South Carolina operations opening their business less than a decade ago.
Similarly, when Tom Bierce of Charleston Oyster Farm first arrived in the Charleston area to study marine science, he realized the opportunity for expansion of mariculture business. Prior to becoming a student, Bierce had an interest in sailing, and while on a voyage he had an unexpected stop in the Northeast U.S. This is where he got a firsthand look at an oyster farm. Bierce began to study oysters more in-depth and quickly became fascinated by the engineering ability of the oyster to shape and stabilize a shoreline. And so, like many other business owners entering the aquaculture industry, Bierce and Davis began to explore the possibilities of growing oysters, and the biggest question was where would be the optimal location?
Lady’s Island Oyster retrieves floating cages from their farm in Beaufort, S.C. in preparation for the grading process. Photo courtesy of Julie Davis.
A lot goes into establishing a mariculture operation, including where you will farm. In choosing a suitable location for a lease, a number of factors are considered. Mainly, water quality of the area and susceptibility to harvest closures guide the siting process from a human health perspective. Consistency of salinity, water depth, tidal fluctuation, and access to the lease also are critical aspects of selecting an area that would both support the optimal growth of oysters and be economically feasible. In addition, both recognizing and understanding other uses of public waterways and gaining community support by enhancing awareness of the operation’s goals are key in getting started. Lady’s Island Oyster, Barrier Island Oyster Company, and Charleston Oyster Farm all service local restaurants, and point out the importance of being within a close proximity of customers to help reduce their carbon footprint.
Like wild oysters, farmed oysters are very distinct in flavor and are unlike any other food of the sea. However, farmed oysters are carefully shaped and monitored, producing the deep-cupped, teardrop-shaped delicacy displayed on raw bars rather than the blade-like bushels of oysters found along grassy marsh shorelines that are typically served at local roasts. Each individual oyster spends 12-18 months on the farm, growing from seed that is only a few millimeters to a market-sized product delivered fresh to restaurants and seafood businesses, often just hours after it is harvested. “Every day is different out on the farm,” say oyster mariculture farmers when asked about their daily routine. Depending on the season, a mariculture operation cycles and prioritizes a range of tasks. In the peak summer, harvests require closer monitoring to abide by temperature regulations and distribution guidelines to ensure consumption safety. Alternatively, cooler months require focusing on farm maintenance, cleaning gear, and shoreline restoration efforts. Farms constantly grade, tumble, and assess oyster growth.
A view of oysters inside a grader, one important step in the farm-to-table process at Barrier Island Oyster Company. Photo courtesy of Will Fontaine.
This attentive process begins by retrieving oysters from the leased area, and then grading them using a tumbler, at which point they are sorted by size and chipped to direct growth into a desirable shape. Once any fouling organisms are removed from the shell, the oyster is processed by hand to chip off overgrowth, tending to each individual oyster to ensure quality. Finally, oysters are either taken back to the farm to grow a bit larger or bagged and prepared for sale. “At any given time, we might have about a million individual oysters on the farm, but each one goes through this meticulous process several times to make sure we get the quality just right every time,” Maddi Piascik of Barrier Island Oyster Company says.
Oyster farmers, star stewards of the environment, feel rewarded by their time on the water and witnessing the wildlife flourish in response to the productive farm processes. Piascik says, “Save the earth, eat farmed oysters,” her face lighting up as she hints towards the bigger picture and value of farm-raised shellfish. “As a keystone species, oysters’ presence positively affects the health of the environment, ecosystem services and benefits, and by extension, people.” As traditional working waterfronts fade due to development, overall salt marsh health and abundance decline, which have larger effects on the coastline. “Being a steward of these ecosystems is of high importance, especially as these waterfronts change and disappear. Oysters, both wild and farmed, help continue a positive loop of preservation,” Piascik asserts.
This is as fresh as it gets! Bierce of Charleston Oyster Farm holds a harvested single oyster. Next stop: a local Charleston restaurant. Photo courtesy of Tom Bierce.
In addition to being tasty, the list of benefits oysters provide is a long one. As Bierce puts it, “The important relationship between oysters and their environment is quite simple, yet scientifically complex. Without clean water oysters can’t survive, and without oysters, our water quality suffers.” In fact, one oyster alone filters dozens of gallons of water per day, improving the waterway and fighting the buildup of excess nutrients that can lead to harmful algal blooms, therefore protecting human health in a number of ways. The presence of oyster reefs equips the shoreline with an extra layer of defense against storm damage and shoreline erosion, produces additional habitat for significant juvenile fish species in the estuary, and are a highly nutritious seafood to enjoy. Davis says, “The more shellfish we have in the water, the better off we all are, whether that is a wild oyster reef, restored oyster reef, or on a farm. They are all performing the same remarkable services, helping people to enjoy their community and contributing to their quality of life on the coast.”
The Barrier Island Oyster Company farmers highlight the team effort of oyster mariculture, shown here bringing cages back to the dock. Photo courtesy of Will Fontaine.
“With new techniques and technology for growing oysters, comes new opportunities for eating oysters,” Davis shares. “As people gain appreciation for these oysters, with that comes their support of what we do on the farms.” While the mariculture industry gains momentum and popularity in South Carolina, operations aim to boost awareness of the value oysters bring to the environment and communities – now and for a sustainable future.
For more information on oyster mariculture or operational and technical support to shellfish growers, contact Sarah Pedigo, the S.C. Sea Grant Consortium’s Shellfish Aquaculture Program Specialist.
Coastal Heritage, Summer 2018—Tank to Table: How Single Oyster Mariculture Works