Ecological Restoration - Sanctuaries & Reserves

The 2004 Chesapeake Bay Oyster Management Plan adopted pursuant to Natural Resources Article, 4-215, Annotated Code of Maryland and Code of Maryland Regulations (COMAR) 08.02.01A directs the Department to establish oyster sanctuaries under Strategy 4.2. The authority of the Department to establish and regulate opening and closing of Harvest Reserves as a fisheries management tool exists under Natural Resources Article 4-1009.1 of the Maryland Annotated Code and COMAR

Current Maryland Oyster Sanctuaries

Following recommendations put forth in the Oyster Advisory Commission's 2008 Legislative Report and a comprehensive Federal/State Programmatic Environmental Impact Statement for Oyster Restoration in Chesapeake Bay completed in June 2009, Governor O'Malley announced Maryland's Oyster Restoration and Aquaculture Development Plan in December of 2009. One objective of this plan was to expand the oyster sanctuary network from 9% to 25% (~9,000 acres) of remaining oyster bar habitat over a broad geographical distribution. Within this enlarged sanctuary network, a number of large areas were selected (up to entire river systems) in strategically located areas for targeted restoration.

Prior to 2009, Maryland's oyster sanctuaries covered only 1,475 acres of bottom habitat. Individually, the sanctuaries were sparsely distributed and small making them difficult to enforce against illegal poaching and relatively ineffective as restoration tools. In 2009, the Department added three new oyster sanctuaries that more than doubled the percentage of protected area yet still protected only 2,581 acres (9%) of geographically dispersed oyster habitat. The remainder of Maryland's portion of the Bay, exclusive of private lease areas, was left open to public shellfish harvesting.

The newest sanctuary areas established in September 2010 were specifically targeted to:

  • Facilitate development of natural disease resistance the long-term strategy for restoring oysters;
  • Protect about half of the Bay's most productive oyster grounds ("best bars") as determined by an analysis of Fall Survey data compiled from 1996 to 2007 (see more detail in FAQ section);
  • Have high restoration potential based on water quality and other factors;
  • Provide essential natural ecological functions that can not be obtained on a harvest bar;
  • Serve as reservoirs of reproductive capacity, generating larvae to populate other areas, including public shellfish fishery areas;
  • Provide a broad geographic distribution across all salinity zones;
  • Increase our ability to protect these important areas from poaching.

It is anticipated that both recreational and commercial fishing will benefit from improved oyster bar habitat in sanctuaries because oyster bar habitat provides critical habitat to blue crabs, striped bass, white perch and other important finfish species. Oysters within sanctuaries are also expected to increase the abundance of adult oysters whose larvae are expected to settle not only within the sanctuary, but also on public shellfish fishery areas in the vicinity of the sanctuaries. A complete list of Maryland's current oyster sanctuaries, listed by region and inclusive of coordinates, can be found here and are shown on the map at right.

Clamming and Leasing in Sanctuaries

As a result of the dramatically expanded sanctuary network, sanctuaries no longer solely consist of natural oyster bars. Instead, the expanded sanctuary network includes additional non-oyster bottom that surrounds the larger areas of interconnected natural oyster bars. The 2010 legislation also modified Strategy 4.2 of the Oyster Management Plan to allow clamming from within the new sanctuary boundaries. The plan limits clamming to existing clamming areas, and maintains the existing 150 foot buffer from any natural oyster bar and leased area. The prohibition of all wild shellfish harvest, including clamming, is maintained for previously established sanctuaries.

Current law prohibits the Department from issuing new aquaculture leases in designated sanctuaries. The Department is however, supportive of this concept under certain conditions, and is pursuing legislative change during the 2011 General Assembly. Aquaculture in sanctuaries under specified conditions can be compatible to restoration by adding to localized water quality improvements, providing ecosystem functions through oyster shell habitat creation, and enhancing natural recruitment of baby oysters within the sanctuary when reproductive oysters are used. If aquaculture leasing were allowed in sanctuaries, the Department is interested in establishing initial limits on the amount of allowed leased area, prohibiting leases on and within 150 feet of natural oyster bars described in the survey of 1906 1912, and implementing stringent penalties for poaching on a natural oyster bar within a sanctuary. Aquaculture leases existing at the time of the enactment of the 2010 legislative changes are excluded from the sanctuary until terminated or surrendered.

Sanctuaries vs. Reserves

Sanctuaries are areas where the wild harvest of oysters, and both oysters and clams in previously established sanctuaries, is prohibited (see above). They often contain oyster restoration projects to help enhance native oyster populations for their environmental benefits. Reserves are areas periodically seeded with oysters or otherwise restored by the Department, then later opened for commercial harvest when the shellfish meet certain criteria, such as a minimum size limit of not less than 3 inches, low disease prevalence and intensity, and other biological reference points. Harvesters are responsible for culling oysters on the Reserve from which they are caught and returning every shell to the bar to serve as settlement substrate for oyster larvae. The Department opens and closes Reserve bars through an established public notice process. To date, Maryland has designated nearly 2 dozen areas as reserves; however, there are a limited number of resources (shell and funding) to support the continued maintenance of reserves.

Note: Other portions of Maryland's oyster harvesting waters may be periodically closed to harvest due to contamination, or high potential for contamination, by fecal coliform bacteria in accordance with the Maryland Department of the Environment (MDE) classification status of oyster and clam harvesting waters. The MDE Shellfish Harvesting and Closure Area Maps can be viewed here.

Frequently Asked Questions (FAQs) About Sanctuaries

Q. Why are you creating more sanctuaries when we need more fishable areas?
A. Sanctuaries are needed to protect the broodstock of the oyster population. The spat these oysters produce will re-seed nearby oyster grounds and will be the source of the harvest of the future. Oyster sanctuaries also provide critical ecosystem services, increasing water quality and clarity and providing habitat. Furthermore, oyster reefs provide habitat for juvenile and adult stages of other commercially and recreationally important fishery species, including blue crabs, striped bass, tautog, drum, sea trout, flounder, sea bass, and of course, more oysters!


Q. Bars need to be power dredged or they'll get smothered with silt and die. How are sanctuaries going to help?
A. Oyster bars do not need to be worked to be healthy. Many bars that have not been power dredged for decades have oyster populations as high as or higher than areas that have been power dredged.


Q. Disease and pollution are the reason oyster populations are low. Why are you only targeting watermen?
A. It is true that disease has devastated oyster populations. It is also true that the pollution is harmful to oysters, particularly those in deeper water. Given the threat of disease and pollution, it is the Department's responsibility to take sensible steps to protect what remains of the oyster population.


Q. These sanctuaries are big. Will there be anywhere left for a waterman to catch oysters?
A. While the acreage of sanctuaries is proposed to increase from 4% of viable oyster bars in 2008 to 24% in 2010, that will still leave 76% of bars accessible to the fishery.


Q. Next year will there be even more sanctuaries and fewer places to catch oysters?
A. No. The Department values the economic and cultural benefits of having a wild oyster fishery. While small sanctuaries may be added for specific reasons, we do not anticipate another large-scale expansion of the sanctuary network in the near future.


Q. Oysters in sanctuaries now just get poached. What good will more sanctuaries do if the oysters are stolen out of them?
A. Oyster theft is a serious problem. The existing sanctuaries, with small closed areas surrounded by fishable waters, were very difficult to enforce. Having large intact closures will allow enforcement to be more effective.


Q. I have heard that most sanctuaries don't even have any oysters in them. If this is the case, why make more?
A. Prior to 2009, very few sanctuaries had been established in areas with productive oyster bars. Areas were chosen to minimize impact to the fishery rather than to protect viable reefs. The sanctuaries proposed for 2010 include some of the Bay's best oyster reefs. With no fishing pressure, we expect to see a jump in oyster populations in these areas.


Q. How were the sanctuary network areas chosen?
A. In order to help set criteria for selecting new sanctuary areas for the Spatial Management Plan, data from the Fall Survey for 1996 - 2007 were analyzed to identify Maryland's most productive oyster bars. The Fall Survey records the number of live and dead oysters in 3 size classes for 25 regions in the Maryland portion of the Chesapeake Bay. Any oyster bar having 4 or more years of high market oyster counts (top 10% relative to the other bars) received a "best bar" designation (see map below). Some characteristics of these 17 "best bars" are that they are:
  • Primarily located north of the Patuxent River;
  • Primarily located on the Eastern Shore;
  • Typically associated with more low and medium salinities and some type of recent rehabilitative treatment (application of dredged shell, fresh shell, and/or seed oysters);
  • Concentrated most highly in the regions of Broad Creek, Little Choptank River, and Eastern Bay.


"Best Bars" Map (view larger version)