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 percent of their teeming 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 offer assistance and information to prospective oyster producers, business owners, commercial harvesters, resource managers, students, and educators.

Increasing the Chesapeake’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, benefitting the entire ecosystem.

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 the remaining 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.

There are no easy fixes to these challenges. Maryland Sea Grant Extension plays an important role in promoting progress in collaboration with federal and state agencies, other university programs, and nongovernmental organizations. Our key efforts are listed below.

Oyster Hatchery

Our Maryland Sea Grant Extension aquaculture specialist, works in cooperation with many partners to operate the Horn Point Oyster Hatchery, which cultivates young oysters for aquaculture and restoration projects. In 2017, the hatchery produced more than 1.7 billion oyster spat (young oysters that are attached to a larger oyster shell), a record. The hatchery works with its 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 to 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.

Maryland Sea Grant Extension also offers oyster hatchery short courses for those interested in working in a hatchery or in starting their own hatchery. In addition, Extension sponsors day-long shellfish conferences with other partners to provide detailed up-to-date information about starting and running an aquaculture business. Brochures and highlights from past conferences are included below. To find out about future courses and conferences, contact Eastern Shore Agent Don Webster.

Advising Policy Makers about Aquaculture

Maryland Sea Grant Extension Eastern Shore Agent 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.

Oyster Gardening

Read about local programs in oyster gardening. That’s where volunteers grow young oysters in cages suspended off docks and later donate them for use in oyster-reef restoration. Jackie Takacs, an Extension watershed specialist, assists with oyster gardening projects in Southern Maryland.

Events

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. 

For More Information

• Maryland Oyster Aquaculture Industry: 2021 at a Glance. This report gives an overview of Maryland’s oyster aquaculture industry as of 2021, including context, cumulative harvest data, monthly harvest data, lease totals and leased acreage, with historic data provided to indicate change over time. 
• Maryland Oyster Aquaculture Industry in 2020 at a Glance. This report gives an overview of Maryland’s oyster aquaculture industry as of 2020, including context, cumulative harvest data, monthly harvest data, lease totals and leased acreage, with historic data provided to indicate change over time. (Maryland Sea Grant assisted with design and production of this report)
• 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
  • Purchasing Seed Oysters
  • Stabilizing Oyster Ground
  • Producing Oyster Seed by Remote Setting

• Northeastern Regional Aquaculture Center aquaculture fact sheets (Maryland Sea Grant assisted with design and production of these publications)

  • Planning for Success in Your Aquaculture Business

  • Freshwater Aquaculture Species for the Northeast

  • Marine Aquaculture Species for the Northeast

  • Aquaculture Systems for the Northeast

  • Environmental Effects of Shellfish Aquaculture in the Northeast

  • Aquaculture Risk Management

• 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 Videos About Oysters

Original productions by Maryland Sea Grant:

• Who Killed Crassostrea virginica—The Fall & Rise of Chesapeake Bay Oysters. (One-hour documentary.) 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. Watch the trailer for the film here:

• Rebuilding the Bay’s Reefs. (Video short.) 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.  Watch the video here: