The interactive map below depicts shellfish harvest areas, state-owned oyster reefs, and permitted areas for on-bottom and off-bottom oyster culture.

The on-bottom oyster harvest season on state-owned reefs is closely tied to the population of oysters present. If the population is determined to be too low to sustain a harvest without causing significant harm to the population, the harvest will remain closed as part of our commitment to biological management. Additionally, there are other circumstances that may lead to the closure of the harvest.

Oysters play a vital role in filtering the surrounding water for nutrients. However, certain substances present in the water column can be harmful to human health if consumed. To safeguard public safety and ensure the well-being of the oyster population, the MDMR issues opening and closing orders based on careful monitoring of water quality.

To facilitate effective management, shellfish growing areas are classified based on ongoing assessments of water quality in those specific locations. These assessments involve regular testing to ensure that the water meets the required standards for safe oyster growth and consumption.

At the MDMR, we prioritize the protection of both public health and the sustainability of oyster populations. We continuously monitor and manage the on-bottom oyster harvest season to strike a balance between harvest opportunities and the long-term well-being of the oyster population.

The classifications are:

  • Approved – Molluscan shellfish growing waters classification used to identify a growing are where harvest of shellfish for direct marketing is allowed.
  • Conditionally Approved – Molluscan shellfish growing waters classification that meets the criteria for approved classification except under certain environmental conditions such as rainfall and river stage. Conditions specific to each area are described in the MDMR Shellfish Bureau management plan
  • Restricted – Molluscan shellfish growing waters classification used to identify a growing area where harvesting shall be by special license and the shellstock, following harvest, is subject to a suitable and effective treatment process through relaying or depuration
  • Prohibited – Molluscan shellfish growing waters classification where the harvest of shellstock for any purpose is not permitted, except depletion, gathering of seed or nursery culture for aquaculture.
  • Unclassified – Waters that are not classified as molluscan shellfish growing waters and from which the harvest of shellfish is prohibited pending classification by the MDMR based on a sanitary survey of the area.