Oyster Restoration in Virginia
Restoring a vital natural and economic resource to Virginia waters.
Oysters are an iconic species in Virginia. Sailing up the Chesapeake Bay from Jamestown, Captain John Smith wrote that they “lay as thick as stones” in the water. For generations, oysters have played an important role in the Bay’s economy as a food that locals, tourists and the global market love.
In fact, it’s possible they have been loved to death.
Overharvest, pollution and disease have decimated oyster populations over the last hundred years. But The Nature Conservancy and its partners are working to turn the tide in an aggressive and concerted effort to restore oyster reefs in 10 Chesapeake Bay tributaries by 2025.
And we’re just getting started.
Oyster restoration has long been a priority for TNC. Oysters filter sediment and algae and remove nitrogen and phosphorus—harmful pollutants in excess—from the water, while their reefs provide nurseries and feeding grounds for rockfish, crabs and other commercially and recreationally important species.
Recent and dramatic changes in the public policy arena, coupled with emerging scientific understanding and the creation of large-scale oyster sanctuaries, are providing a clear path forward to restore this keystone species.
In 2020, TNC contributed to the construction of 40 acres of reef in Virginia’s Piankatank River, bringing the total to 146 acres planted on more than 15 reefs since 2014. In 2021, the Virginia Marine Resources Commission (VMRC) constructed over 60 acres of new reef, with the Army Corps of Engineers slated to add 50 acres in 2022—expanding the world-record reefs in the Piankatank to almost 500 acres.
TNC has invested nearly $1 million into this decade-long effort, leveraging nearly five times that amount from our partners and surpassing the shared goals we set out to achieve for oyster restoration in this key tributary of the Chesapeake Bay. Working with partners, including the Army Corps of Engineers, VMRC and NOAA, we’re building on success and on pace to exceed the goal of 438 acres of oyster restoration in the Piankatank by 2025.
What does that number represent? An area bigger than the National Mall in Washington, D.C., and representing the largest oyster restoration project in the world.
Reefs have been constructed using clean, crushed concrete or granite. High pressure water hoses are used to deposit the smaller sized substrate; floating cranes and barges are used to precisely place the granite in rows along the reef sites.
The Piankatank River was selected in part because of its unique flow and strong natural retention of oyster larvae. Considered a trap estuary, the circulatory pattern of water in the river helps to retain oyster larvae that will eventually attach to the hard substrate in the system (like the concrete and granite being placed by TNC) where the spat will grow. With the high productivity of the system, there is a high probability that restoration efforts will result in self-sustaining oyster populations.
With an economic return of $7 for every dollar invested, oyster reef restoration in the Piankatank River is an important step towards bringing a vital natural—and economic—resource back to the Chesapeake Bay.
By restoring and repopulating large oyster reefs in key parts of the bay, we hope to reach a tipping point where oyster populations become sustainable, expanding their numbers and the benefits they and their reefs provide.
Oyster reef restoration also offers a nature-based solution for adapting to climate change. Reefs can take the punch out of storm waves and help slow the rate of erosion along marsh edges. As they grow, oyster reefs accrete vertically, keeping pace with sea level rise and increasing their capacity for storm protection.
The Eastern Shore's unique expanse of Atlantic coastal wilderness offers unparalleled opportunities to study how local communities can benefit from intact natural systems, and the advantages of restoring coastal habitat.
TNC worked with VMRC in 2015 to build two oyster reefs at Man and Boy Marsh. Three additional reefs were constructed in 2016 at two sites at Chincoteague National Wildlife Refuge that suffered serious damage from Hurricane Sandy. These projects were funded by both the U.S. Department of Interior and the National Fish and Wildlife Foundation through funds established to support Hurricane Sandy recovery efforts.
We worked closely with partners on these projects, including the U.S. Fish and Wildlife Service, National Park Service, U.S. Department of the Interior, Virginia Department of Game and Inland Fisheries, and VMRC.
In 2017 we launched a new project with the University of Virginia to build eight experimental reefs at Short Prong Marsh. The goal is to measure how different designs affect wave energy, and to determine which designs are most effective at slowing the rate of erosion along the marsh edge.
All of these reefs are constructed from concrete castle blocks. Fitting the interlocking blocks together may look like child’s play, but each piece weighs 30 pounds! The castle blocks are placed in uniform arrays that will provide a foundation on which juvenile oysters can attach and build.
Oysters Down Under: Collaborating with Colleagues
Restoring native oyster populations is a global concern. In Australia, as in the Chesapeake Bay and its tributaries, shellfish suffered dramatic declines during the first half of the 20th century. By 1948, South Australia’s once-abundant wild oyster fishery had closed. The area’s shellfish reefs, along with all the other marine life they supported, had become functionally extinct.
In 2018, Andy Lacatell, Virginia's Chesapeake Bay program director, and VVCR Coastal Scientist Bo Lusk traveled to Australia to present the keynote at the 19th International Conference on Shellfish Restoration in Adelaide. The trip provided an opportunity for both inspiration and collaboration with TNC colleagues down under.
TNC is partnering with the South Australian Government, Yorke Peninsula Council, and the University of Adelaide to rebuild a $4.2-million shellfish reef across 50 acres in the Gulf St. Vincent. The Windara Reef will be the largest such restoration effort ever undertaken in Australia.
Restoration efforts are also underway in Port Phillip Bay near Melbourne with partners including the University of Melbourne, Fisheries Victoria, and the century-old Albert Park Yachting and Angling Club. Club members are helping to identify potential reef bottom based on their expertise and knowledge of the bay's waters.
Integral to these partnership and decisions to invest significant resources is the demonstrated success of oyster restoration in the United States, including projects in the Piankatank River and at the Volgenau Virginia Coast Reserve.
Chesapeake Bay: Aquaculture by Design
Our efforts in the Chesapeake Bay and at the Volgenau Virginia Coast Reserve have primarily focused on supporting wild oyster populations, but the Bay’s oyster aquaculture industry is the largest on the East Coast. There is some evidence that it can have positive impacts on the ecosystem - but the impacts have never been fully quantified.
To develop a better understanding of the specific connections between oyster aquaculture and water quality, TNC partnered with the Virginia Institute of Marine Science and four oyster growers—Big Island Aquaculture, Chapel Creek Oyster Company, Lynnhaven Oyster Company and White Stone Oyster Company—to answer the question: can oyster aquaculture make the bay cleaner, faster?
After sampling and studying environmental variables at each of the four oyster farms including water currents, water clarity and chemistry, and sediment type (and the creatures that live in it), our research indicates that oyster aquaculture is a low impact way of producing animal protein.
The data indicate that the oyster aquaculture industry can help to restore water quality in our rivers and bays. For every 100,000 oysters grown and harvested annually, six pounds of nitrogen and phosphorus pollution are removed from the Bay. Oyster farms may also reduce wave energy and help protect vulnerable shorelines.
As oyster aquaculture grows, so will the food and water quality benefits to the Chesapeake Bay.