Restoring What Was Lost: How Science and Community Are Bringing Back Bay Scallops
After nearly a century of extinction, seagrass restoration and other conservation work could lead to a scallop resurgence in Virginia’s coastal bays.
Through decades of conservation and seagrass restoration work by The Nature Conservancy and our partners, Virginia’s bay scallops are returning to the Eastern Shore after almost a century of extinction. These results show what is possible when scientists and communities work together to restore our marine habitats.
Sea Changes
Marine Habitat Restoration
A century ago, Virginia was a leading producer of bay scallops in the country. The scallops fueled the local economy and became a favorite food enjoyed by the region. About 91 million scallops—or 1.8 million pounds of seafood—were harvested in 1930, according to research led by the University of Virginia’s Matt Oreska. Within a few short years, a disease wiped out the local seagrass, a critical habitat for bay scallops, who hide from predators and currents within the blades. Then the scallops completely disappeared.
This was the story TNC Coastal Scientist Bo Lusk heard from his grandmother, who grew up along the Eastern Shore. She witnessed watermen lose their livelihoods as the scallop population dwindled. Today, as part of TNC’s Volgenau Virginia Coast Reserve (VVCR), Lusk has been able to continue writing his grandmother’s story toward a happier ending.
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SubscribeIn the late 1990s, after researchers from the Virginia Institute for Marine Science (VIMS) discovered a stray patch of eelgrass in a bay off the Eastern Shore, they had a eureka moment. According to Dr. Robert “JJ” Orth from VIMS, “That’s when the light went on that conditions there might be ripe for recovery, as long as there was a source of seeds.” Over the next few years, TNC began working closely with VIMS to accelerate the spread of eelgrass (Zostera marina). Seeds are harvested from eelgrass in the late spring, then cast into selected zones in the early fall. In the span of 25 years, these seagrass beds have spread from near zero to nearly 12,000 acres through our conservation work. The effort has grown so large that now, every spring, dozens of TNC volunteers suit up to snorkel and collect the underwater plants for seed curing.
The reintroduction of bay scallops could not have been possible without seagrass restoration, as well as more than 50 years of TNC’s land protection efforts at VVCR, which now encompass 14 barrier and marsh islands. These undeveloped islands—the longest expanse of coastal wilderness remaining on the East Coast—maintain the water quality needed to restore this marine habitat.
A Tale of Two Species
Bay Scallop Restoration
By 2009, we had recovered enough seagrass to try to support our first population of bay scallops (Argopecten irradians) in the wild. For the trial run, VIMS released 5,500 hatchery-raised scallops into the coastal waters.
Barry Truitt—TNC’s VCR chief conservation scientist at the time—secured American Recovery and Reinvestment Act (ARRA) funds through the National Oceanic and Atmospheric Administration that year, and part of that grant paid for VIMS to launch our bay scallop restoration efforts.
VIMS has spawned adult scallops at the Eastern Shore Laboratory every spring since. To start the process, scientists gently warm scallops to induce spawning, which produces larvae so small they can only be seen under a microscope. Once the larvae grow into tiny scallops in tanks, they are relocated to the lab’s nursery. After about two months, VIMS rehomes the scallops into bayside cages, similar or identical to those used in oyster farming. Located in South Bay and Burton’s Bay, these cages safeguard the young scallops from predators and keep them close enough to each other to breed. Their microscopic offspring float around the bays for about 10 days until they settle on blades of eelgrass. Eventually, these will grow into the wild scallops we now find throughout the water.
Monitoring the population is another essential and demanding stage in the scallop restoration process. In just three days every July, teams of TNC and VIMS scientists, staff and volunteers boat to nearly 240 stations throughout the southern coastal bays. Once submerged in up to four feet of water, they feel for the scallops’ hard shells tucked within the soft grass to count and measure them. Each team combs through nearly 12,000 square meters, or a little over two football fields, of seagrass meadow at every station.
Within 17 years of our efforts, there have been periods of exponential population growth over several consecutive years, which is unusual for the species. Because bay scallops only live up to two years and are highly sensitive to environmental changes, population growth is difficult to sustain. This makes our coastal conservation work even more critical moving forward.
“The scallop restoration has been amplified by the continued success of the eelgrass restoration to create a stable habitat, in addition to favorable weather conditions and water quality,” explains Darian Kelley, VIMS scallop nursery manager.
“To see TNC’s land protection work potentially lead to the return of a species that generations of my family saw disappear is incredible,” Lusk says.
Ripple Effect
Climate Mitigation
The loss of eelgrass had a profound ripple effect on our coastal ecosystem and so has its restoration. Other popular seafood species, like red drum and speckled trout, are returning to the underwater meadows. On a broader scale, the return of eelgrass and scallops mitigate the increasingly severe effects of climate change. Scallops are efficient water filters, which improve water quality for all species, while eelgrass acts like a massive carbon sponge.
Five acres of eelgrass can soak up enough carbon dioxide to offset driving a car 15,000 miles a year.
Today eelgrass covers the coastal bays around South, Spider Crab, Hog Island and Cobb Island. This work is the largest successful seagrass restoration project in the world and has been used as a model for restoration work across the globe.
Learn About Conservation
Volgenau Virginia Coast Reserve
Empowering resilient coastal communities on Virginia's Eastern Shore.
Restoring Eelgrass on Virginia’s Eastern Shore
Go into the water and behind the scenes at the Volgenau Virginia Coast Reserve for the largest successful seagrass restoration project in the world!
Marine Habitat Restoration
From building oyster reefs to establishing the largest successful eelgrass restoration effort in the world, we're putting science to work in Virginia's coastal bays.