Shellfish experts from across Europe have come together and agreed on a series of conservation strategies aimed at protecting at-risk stocks of native flat oysters (Ostrea edulis).
While the European flat oyster represents a key species with important ecological functions in the marine ecosystem, stocks are classified as highly endangered all over Europe. Indeed it is considered to be extinct in large parts of Europe and the German North Sea.
Initiated by the German Federal Agency for Nature Conservation (BfN), the new Native Oyster Restoration Alliance (NORA) was established during the recent first international workshop on oyster restoration that was held in Berlin. The alliance’s long-term goals are to re-establish the European flat oyster as a former key species in the North Sea and adjacent European seas as well as to extensively restore species-rich oyster reef structures.
If successful, the alliance believes it could contribute to greatly improved water quality and biodiversity in these waters.
European scientists at universities, nature conservation agencies and organizations – also within BfN – have been active in research, restoration and protection of the European flat oyster for many years. At present, restoration projects are being conducted in the United Kingdom, Ireland, the Netherlands and Germany.
Among these, University of Portsmouth marine biologist and a founder member of NORA Dr. Joanne Preston is leading a project in partnership with the Blue Marine Foundation and MDL marinas that aims to restore the native oyster population in the Solent, off the south coast of England, which once supported the biggest oyster fishery in Europe.
"Oyster beds are considered to be biodiversity hot spots. By filtering large volumes of water, oysters also improve water quality on local scales. A single oyster can filter up to 200 liters of sea water per day – multiply this by millions of oysters, which historic records suggest populated the North Sea in the past, this could provide a significant eco-service which acts in a manner similar to giant biological water treatment plant," she said.
