Wetlands on the Manokin River are seen on Maryland's Eastern Shore. The Manokin River was recently chosen as the tenth and final tributary for oyster restoration under the 2014 Chesapeake Bay Watershed Agreement. (Image by Will Parson/Chesapeake Bay Program)

The Manokin River, located in Tangier Sound off the Eastern Shore of Maryland, is the final tributary to be selected for large-scale oyster restoration by the Chesapeake Bay Program. The Chesapeake Bay Watershed Agreement calls for the restoration of the native oyster population in 10 tributaries by 2025.

Although designating Manokin River as the tenth and final tributary is a major milestone, the outcome is not considered complete. The partnership must develop a tributary restoration plan for each site, construct and seed reefs, and then monitor and evaluate the reefs for progress. Only two sites—Harris Creek in Maryland and the Lafayette River in Virginia—are considered complete.

Both Maryland and Virginia have identified five sites each for large-scale oyster restoration. In Maryland, in addition to the Manokin River, are Harris Creek and the Little Choptank, Ted Avon and the Upper St. Mary’s rivers. In Virginia, the sites selected for oyster restoration are the Great Wicomico, Lafayette, Lower York, Lynnhaven and Piankatank rivers.

The most recent Maryland Oyster Restoration Update notes that 773.58 acres of oyster reefs have been restored in Harris Creek, and the Little Choptank and Tred Avon rivers. St. Mary’s River was approved for oyster restoration in December 2018 and partners are working on its restoration plan.

The 2018 Virginia Oyster Restoration Update states that 510 acres of oyster reefs have been restored by either constructing reefs, seeding or are otherwise already considered healthy. Two hundred and twenty-one acres of reefs remain to be restored in the Lynnhaven and Piankatank rivers. The Great Wicomico and the Lower York rivers were approved as restoration sites in December 2017 and restoration plans are under development.

Large-scale oyster restoration is truly an example of what can happen when many partners work together. Funding comes from a variety of sources, including federal, state and local governments, as well as non-profit organizations. The Maryland and Virginia Oyster Restoration Interagency Team is made up of representatives from the National Oceanic and Atmospheric Administration (NOAA), U.S. Army Corps of Engineers, Oyster Recovery Partnership, Virginia Marine Resources Commission and Maryland Department of Natural Resources, among others.

Oysters are ecologically valuable as filter-feeders that clean the waters of the Chesapeake Bay and its tidal tributaries by pumping water through their gills and trapping food particles, nutrients, suspended sediments and chemical contaminants. Oysters also play an important role in the Bay’s resilience to climate change. They help protect shorelines from strong waves, reducing the extent of property damage caused by extreme weather.

However, disease, historical overharvesting, poor water quality and habitat loss have led to a severe drop in oyster populations over the last century. Excess nutrients in the water fuel the growth of algae blooms that create low-oxygen “dead zones” that can kill oysters or hinder their development. Stress related to poor water quality can make oysters more susceptible to disease and impacts reproduction. Additionally, as clean shell is vital habitat for oysters, any sediment that covers it has the potential to cause suffocation. As a result, native oyster populations in the Chesapeake Bay are at less than one percent of historic levels, which is why these large-scale oyster restoration projects are so important.

“Oyster reefs provide needed fish habitat benefiting both the ecology of the Chesapeake Bay and the economy of the region,” says Sean Corson, acting director of NOAA’s Chesapeake Bay Office. “At NOAA, we’re delighted to have our science, technical planning and financial support make this effort possible.”

Learn more about our goal to restore 10 native oyster reefs on www.ChesapeakeProgress.com.



David Baker

It is a great cycle. Oysters are restoring the bay while the bay is restoring the oyster.

Global Oyster Restoration Network


We are working to boost recognition of Oyster restoration globally. Could you please add your restoration sites to our map?


Sonia Koetting

We hear about coral reef restoration, but much less about oysters. It's discouraging that the population has dropped to 1 percent. But encouraging that so much work is not being done! Oysters, too, play their part in stabilizing climate events.

Thanks for defending and restoring beautiful Chesapeake Bay!!

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