Governor Wes Moore announced on August 26, 2025, that Maryland has fulfilled its commitment under the 2014 Chesapeake Bay Watershed Agreement by completing oyster restoration in five tributaries, culminating with the Manokin River Sanctuary on the Lower Eastern Shore. The projects, among the largest oyster restoration efforts worldwide, have boosted oyster populations, enhanced habitat and supported economic growth in the Chesapeake Bay.
“This restoration supports our commitment to bringing the oyster population back in five rivers by 2025 and the larger effort to support the repopulation of oysters in the Chesapeake Bay, which has more than tripled in the past 20 years,” said Gov. Moore. “Our success represents the best of government collaboration to systematically address a complex environmental issue with real economic impact.”
Oysters drive Maryland’s commercial fishing industry, with average dockside value rising more than 300 percent since restoration began. Watermen harvested an average of 475,000 bushels annually over the past five years, yielding over $18 million in dockside value, compared to 116,000 bushels and $3.5 million annually from 2005 to 2010.
As a keystone species, oysters filter water and provide habitat for fish and other aquatic life. The sanctuaries remain closed to harvest except for aquaculture leases, allowing undisturbed growth for ecological benefits. Scientists aim to expand the Bay’s spawning stock and foster natural disease resistance through these protected areas.
Maryland Department of Natural Resources Secretary Josh Kurtz joined federal, university and nonprofit partners for a final oyster deployment in the Manokin River, adding thousands of spat-on-shell to mark the end of 14 years of large-scale oyster restoration. Virginia also completed its five tributaries under the agreement.
“The Manokin River sanctuary is the last phase of a decade-plus investment in oyster restoration,” said Maryland Department of Natural Resources Secretary Josh Kurtz. “Now, as we wrap up restoration here, we can see how far we’ve come. We’ve been so impressed by the success in these restoration sanctuaries. These productive oyster reefs are a testament to the hard work our staff and partners have dedicated to this effort, and they show us how oysters can thrive when we support them.”
Partnerships fueled the initiative. The National Oceanic and Atmospheric Administration supplied funds, expertise and monitoring. The U.S. Army Corps of Engineers built reef foundations using stone, shell and substrates. The University of Maryland Center for Environmental Science’s Horn Point Laboratory produced billions of spat-set shells. Nonprofits like the Oyster Recovery Partnership and Chesapeake Bay Foundation distributed juvenile oysters.
In 2019, the Maryland General Assembly protected these sanctuaries permanently from harvest. Total investment exceeded $92 million from state and federal sources, restoring 1,300 acres of reefs.
“The Oyster Recovery Partnership is proud of the strong partnership with the Maryland Department of Natural Resources and our shared vision to revitalize Maryland’s oyster populations,” said Oyster Recovery Partnership Executive Director Ward Slacum. “The completion of the Manokin River oyster sanctuary represents a historic achievement for Maryland and for oyster restoration globally. This significant milestone was made possible by the collaborative efforts of all involved partners, who have demonstrated an unwavering commitment to a healthier Chesapeake Bay.”
Other completed sanctuaries include the Little Choptank River in Dorchester County, the St. Mary’s River in St. Mary’s County, Harris Creek and the Tred Avon River in Talbot County. Monitoring shows dense three-dimensional reefs, multiple oyster age classes, increased biomass and natural reproduction. The 2025 stock assessment reported Maryland’s Bay oysters rose from 2.4 billion to 7.6 billion in 20 years, with 700 million added in the first three sanctuaries.
The Manokin sanctuary spans 455 acres, exceeding the 441-acre plan, with 1.39 billion hatchery-set oysters planted. Designated in 2010 and selected for large-scale oyster restoration in 2019, work started in 2022 under Department of Natural Resources oversight.
“We are proud of our key position in the partnership, producing juveniles to restore the Chesapeake Bay oyster populations,” said University of Maryland Center for Environmental Science Horn Point Laboratory Director Michael Sieracki.
Funding included Maryland capital funds and a NOAA grant for larvae production, totaling $21.6 million by 2024. The Army Corps aided planning and construction, while NOAA handles post-restoration monitoring.
“The Baltimore District is proud to be part of the team that has contributed to large-scale oyster reef restoration efforts in Maryland and toward the Chesapeake Bay Program’s goal to restore oyster reefs in 10 Chesapeake Bay tributaries by 2025,” said USACE Baltimore District Commander Col. Francis Pera. “Preservation of our Bay contributes to national security by ensuring both economic and ecological vitality for those who live and work in its watershed for generations to come.”
Early Manokin results encouraged, with 2024 natural spat set obviating hatchery planting on 90 acres, saving $1.8 million.
“Large-scale oyster restoration is working,” said Chesapeake Bay Foundation Maryland Executive Director Allison Colden. “In Maryland, the oyster population has tripled since 2005. And we’re excited that Maryland DNR has already committed to restore three additional oyster sanctuaries in the state. This event marks a momentous achievement, but also the beginning of the next phase of oyster restoration. We’re eager to keep up the momentum and continue our collaborative work towards a restored oyster population in Chesapeake Bay.”
Maryland advances next, selecting Herring Bay, Nanticoke River and Hoopers Strait sanctuaries. The department plants in Eastern Bay, supporting sanctuaries, aquaculture and harvest areas.
In Southern Maryland, the St. Mary’s River sanctuary, completed in 2022, restored 60.2 acres starting in 2021. Efforts included rebuilding three-dimensional habitat, aiding water filtration and species like blue crabs. Local groups, scouts and volunteers planted over 30,000 juvenile oysters in June 2025 via the Marylanders Grow Oysters program.
Oyster restoration yields economic benefits. A NOAA report examined Choptank River effects, noting habitat gains for fisheries and regional jobs. Maryland’s shellfish aquaculture contributes over $13 million annually. In St. Mary’s County, restoration supports watermen and tourism tied to the Bay.
The Chesapeake Bay Watershed Agreement, marking its 10th year in 2024, targeted 10 tributaries Bay-wide. As of July 2025, partners restored 2,294 acres, meeting goals. Veterans aided 2025 efforts, planting in sanctuaries for ecosystem and therapeutic benefits.
Historically, overharvesting, pollution and disease decimated oysters to 1 percent of peaks. Restoration counters this, with Harris Creek fully successful. Future sites build on this, with planning underway. These efforts ensure sustained ecological and economic vitality for Maryland communities, including Southern Maryland’s waterfront areas.
