Knauss legislative fellowships in Congress help build careers — and they're fun and educational. See our video and fact sheet for details.
Oyster Aquaculture and Restoration
Disease, habitat loss, overharvesting, and poor water quality have left the Chesapeake Bay’s iconic wild oysters in a dismal state, at just 0.3% of their abundant population in the early 1800s, according to a 2011 research study by the University of Maryland Center for Environmental Science.
Maryland Sea Grant Extension works with partners to bring oysters back to the Bay by using aquaculture to grow oysters for food and restoration. Our programs:
- Provide seed for oyster aquaculture and restoration of wild oysters
- Offer technical advice about aquaculture methods, business financing, and public policy
- Support public education
We work with prospective oyster producers, business owners, commercial harvesters, resource managers, students, and educators.
Increasing the Chesapeake Bay’s oyster populations is a high priority in Maryland. Oysters' ability to filter vast amounts of water improves water quality. Oyster reefs also provide habitat for a variety of fish. However, restoring self-sustaining populations of wild oysters to a significant level may prove difficult because of ecological, economic, and cultural hurdles. For example, generations of Chesapeake watermen have harvested wild oysters from grounds scattered around the Bay. Encouraging watermen to embrace aquaculture—oyster farming at fixed locations—is a challenging proposition, because this business requires a different set of skills and substantial start-up costs.
Maryland Sea Grant Extension plays an important role in promoting progress in collaboration with federal and state agencies, other university programs, and nongovernmental organizations. Learn more about our key efforts below.
Oyster Hatchery
Our aquaculture specialist works with many partners to operate the Horn Point Oyster Hatchery, which cultivates young oysters for aquaculture and restoration projects. In 2017, the hatchery produced a record of more than 1.7 billion oyster spat (young oysters that are attached to a larger oyster shell). The hatchery works with partners to distribute oysters for commercial aquaculture and to build up oyster reefs in the Bay. Learn more about these projects on the hatchery's website.
Assistance for Aquaculture Businesses
Maryland Sea Grant Extension helps individuals and companies obtain financing and technical know-how to start aquaculture businesses in the Bay. An Extension specialist helps entrepreneurs to apply for low-interest loans from the state of Maryland. This program is targeted for watermen who want to transition from harvesting wild oysters to growing them through aquaculture; the money helps them buy equipment.
Our resources include a spreadsheet and instruction booklet about remote setting, a technique for producing oyster seed from larvae. These materials help operators to evaluate costs and feasibility. Learn more about resources from Extension personnel, including aquaculture business specialist Matt Parker.
We also offer oyster hatchery short courses for those interested in working in a hatchery or starting their own hatchery. In addition, Extension sponsors day-long shellfish conferences with partners to provide up-to-date information about starting and running an aquaculture business. To find out about future courses and conferences, contact eastern shore specialist Don Webster.
Communicating with Policymakers
Research Brief: Oyster Aquaculture and Submerged Aquatic Vegetation
Bay grasses, or submerged aquatic vegetation (SAV), play a key role in the Chesapeake Bay—providing habitat, improving water quality, and serving as an indicator of Bay health. Because SAV is a protected resource, its presence can influence how and where aquaculture operations are conducted.
In a new research brief, we explore findings from recent studies on two bottom-cage oyster farms in Southern Maryland. The publication examines the effects of oyster aquaculture on SAV and includes considerations for policymakers and oyster growers.
Shellfish Aquaculture Expansion
Eastern shore specialist Don Webster has played a vital role in working to promote major changes in state policies that allowed significant expansion of shellfish aquaculture throughout the Chesapeake Bay. The legislation expanded the area of the Chesapeake Bay that can be leased for oyster harvesting and the categories of eligible lease holders. Learn more about oyster aquaculture policy.
Oyster Gardening
Read about local programs in oyster gardening, where volunteers grow young oysters in cages suspended off docks and later donate them for use in oyster reef restoration.
For More Information
- Maryland Oyster Aquaculture Industry: 2023 at a Glance. This report gives an overview of Maryland’s oyster aquaculture industry as of 2023, including context, cumulative harvest data, monthly harvest data, lease totals and leased acreage, with historic data provided to indicate change over time.
- Oyster Production Equipment Comparison 2016–2018. This report shares findings from a two-year study comparing available oyster aquaculture equipment, which collected data on oyster production and equipment cost. Information from this project will allow farmers to make informed decisions regarding purchases, operation, and lease management. (Maryland Sea Grant assisted with design and production of this report)
- Biofouling Control Strategies: A Field Guide for Maryland Oyster Growers. A field guide of plants and animals that can colonize oysters for identifying common biofouling organisms in the Chesapeake Bay. Produced by our Extension agents, it includes images of each species, along with where it's found, how it influences oysters and/or gear, and effective treatments.
- Shellfish Aquaculture Lease Transfer Fact Sheet. This fact sheet answers the frequently asked questions about the process of transferring a commercial shellfish lease. It was developed in collaboration with the Maryland Department of Natural Resources and Maryland's Agriculture Law Education Initiative. (Maryland Sea Grant Law & Policy Fellow Elissa Torres-Soto prepared this document and the communications team provided copyediting and design)
- Fact sheets and reprints about oyster aquaculture
- Northeastern Regional Aquaculture Center aquaculture fact sheets (Maryland Sea Grant assisted with design and production of these publications)
- University of Maryland Extension Oyster Aquaculture and Education Program
- Shellfish aquaculture conference materials
- Reprints from the Maryland Sea Grant Store
- Shellfish Aquaculture Development in Maryland and Virginia: Economy, Employment, Environment. This 2009 report produced by the Sea Grant programs of Maryland and Virginia and commissioned by the NOAA Chesapeake Bay Office details the history of shellfish aquaculture in the Bay and sets out current opportunities and challenges.
- Maryland Oyster Aquaculture History & Policy: Background Documents Prepared for the Maryland Oyster Advisory Commission. These are a series of documents prepared by Extension agent Don Webster for the Maryland Oyster Advisory Commission about the past and future of oyster aquaculture in Maryland. The reports identify problems facing the industry during the past three decades as well as potential solutions for rebuilding a profitable and ecologically beneficial oyster industry.
- Native Oyster Restoration in Maryland and Virginia: An Evaluation of Lessons Learned 1990-2007—A Preliminary Report. Insufficient data exist to show whether oyster-restoration efforts in the Bay have resulted in increasing numbers of oysters, according to a review by a scientific panel and summarized in this report. Their summary recommends improvements in data collection and the coordination of restoration efforts.
- Oyster Restoration Workgroup. This group studies how to promote and measure the success of shellfish restoration projects. How to measure success or failure is a key question about which little consensus exists among experts. The group’s website promotes a forum for these discussions, professional networking, and a repository of links to the latest literature, including suggested approaches for measuring restoration success based on a suite of agreed upon goals and associated metrics. The workgroup’s focus includes intertidal and subtidal oyster reefs. Sponsors include several academic and nonprofit organizations.
- A Future for Oyster Farming, an entire issue of Chesapeake Quarterly, Maryland Sea Grant’s magazine.
- Maryland Aquafarmer archive. This newsletter about aquaculture was produced from 1995 to 2005 by the Cooperative Extension Service, University of Maryland at College Park, in cooperation with Maryland Sea Grant.
- See links to more information from Maryland Sea Grant about oysters—scholarly publications, educational curricula, news articles, and videos.
Featured Oyster Videos
Oyster Aquaculture Education Series
Learn about setting up and maintaining a remote setting system for oyster aquaculture from Maryland Sea Grant Extension. View the oyster aquaculture video series.
Who Killed Crassostrea virginica—The Fall & Rise of Chesapeake Bay Oysters
The Chesapeake was once home to the richest oyster grounds in the world. Who killed the Bay's native oysters? This award-winning, hour-long documentary sets out to answer that question. The film details both the poignant destruction of a fabled fishery and the prolonged scientific inquiry into the origins of a killer parasite. Purchase the DVD from our Bookstore.
Rebuilding the Bay’s Reefs
At the University of Maryland's Horn Point Hatchery, Don Meritt turns out seed oysters full of oyster spat (baby oysters), and Charlie Frentz of the Oyster Recovery Partnership plants them in the Chesapeake Bay.
Past Workshops
Maryland Sea Grant has held several workshops to engage with and support the aquaculture industry.
- 2017 Maryland Shellfish Aquaculture Industry Roundtable Workshop. Local Maryland shellfish growers were invited to participate in a two-part workshop series as part of Maryland Sea Grant's continuing efforts to engage with and support the aquaculture industry.
- 2018 Maryland Sea Grant Aquaculture Researcher Roundtable. As a complement to the Maryland Sea Grant 2017 Maryland Shellfish Aquaculture Industry Roundtable, participants were invited from the fields of research, extension, and industry to further discuss ongoing issues for Maryland aquaculture farmers.
Program Announcements
News and Blogs
Featured Fellow
Nina Santos
Nina Santos is a Ph.D. student at the Chesapeake Biological Laboratory at the University of Maryland Center for Environmental Science. For her dissertation, she is focused on small shrimp-like crustaceans called mysids – an understudied yet important part of many estuarine and coastal food webs.
Featured Research Project
Developing a habitat model for mysids, an important link in Chesapeake Bay food webs
Mysids are important mesozooplankton prey for many species of fish in Chesapeake Bay and are an important link in transferring energy from lower to upper trophic levels. Mysids also serve as biological vectors for benthic-pelagic coupling due to their diel vertical migration and omnivorous prey-switching behavior, which makes mysids important regulators of food web architecture. Despite their central role in coastal food webs, surprisingly little is known about mysid ecology and dynamics in Chesapeake Bay.
