In 2020, as part of the Foundation’s research into improving coastal resilience at impacted salt marshes, we began preliminary research to see if the intertidal shore of Medouie Creek would make good habitat for an oyster reef. Oyster reefs have the potential to serve as natural shoreline erosion buffers that also have important ecological benefits. Theoretically, an appropriately placed oyster reef can slow down wave and tide impacts, protecting an impacted shoreline from erosion and even allowing a salt marsh to naturally expand towards the reef.
At the Medouie Creek salt marsh, we have been experiencing salt marsh dieback and have exposed soil that can be easily eroded away and while we are working actively to restore the marsh, it is still susceptible to erosion during that time.
The process of building an oyster reef and getting permission to build an oyster reef is extensive. The Foundation worked closely with the Town of Nantucket’s Natural Resources Department and their Shellfish Hatchery to conduct preliminary site monitoring. Once we determined the shoreline of Medouie Creek would be good oyster habitat, we designed a reef that would buffer the shoreline.
We decided to build the reef out of Oyster Castles, interlocking concrete blocks that provide a surface for oysters to attach too. A third of the reef’s castle blocks were taken to the TON NRD’s Shellfish Hatchery to grow baby oyster spat on, prior to building the reef.
In November 2021, all permits were approved for the project and Foundation staff with volunteers from many island conservation groups came together over three days to build the linear oyster reefs to project Medouie Creek. We will spend the next five years monitoring many aspects of this project from erosion of the marsh shoreline to the health and growth of the oysters on the reef. This project is the first of its kind in Massachusetts and will provide examples of another way to increase shoreline resilience. This project was funded primarily by the MA In-Lieu Fee Program with additional funding from the Nantucket Shellfish Association.