Evaluating Methods to Enhance Oyster Production with Alternative Substrates, Retrofits, and Hatchery Holding Times
A Report to the Maryland General Assembly, Governor, and Secretary of Natural Resources in Response to Senate Bill 830 (2022)
This report is in response to Senate Bill 830 (2022) that instructed the University of Maryland Center
for Environmental Science (UMCES) to evaluate the following topics in collaboration with Smithsonian
Environmental Research Center, Virginia Institute of Marine Science, appropriate State and federal
agencies, and industry and other stakeholders:
1. The types of substrate, including fresh shell, fossilized shell, combinations of shell, and
alternative substrates, that are most appropriate for use in oyster harvest areas;
2. The benefits, including habitat–related benefits, of using stones of various sizes in oyster
restoration areas;
3. Alternative substrates used for oyster restoration or repletion in other regions, including the
success of efforts to use alternative substrates;
4. The potential for retrofitting existing structures, such as riprap revetments, that are unrelated to
oyster restoration but that use materials similar to artificial reefs, to include oyster plantings,
5. The effect of spat size upon deployment on oyster abundance.
The five chapters of this report correspond to these five topics.
Keywords: Oysters, Oyster Hatchery, Retrofits, Alternative Substrate for Oysters, Oyster harvest, Oyster Habitat, Spat, Shell
