The European Oyster (ostrea edulis) tends to live in deeper water than the Eastern Oyster that we are working to restore.
The European oyster was imported to Maine in the 1950s for aquaculture. We have heard that they were accidentally released from a Massachusetts North Shore aquaculture facility when the wrong valve was mistakenly opened. A 1997 survey revealed dense concentrations of O. edulis in Salem Harbor, Danvers River, and Manchester Bay (Salem Sound). Lower densities were observed north to Cape Ann and south to Boston Harbor. They continue to be harvested in Casco Bay, Maine. In the Northeast, O. edulis appears to occupy a different niche than the native oyster population, and it is yet to be determined if there are ecological impacts.
We have seen O. edulis shells throughout the harbor and our divers had even found one at the mouth of the Charles River. Below is a picture of one Mat has found on a May dive.