General Information About Oysters
Fast Facts 
- A 3-inch or larger adult oyster can filter up to 60 gallons of water a day.
- The pre-colonial population of native oysters was able to filter the entire volume of the Chesapeake Bay in approximately 3 days. Today’s population (estimated to be at 0.2 % of the pre-colonial population) takes several years to do so.
- Estimates of the extent of historic reefs in the Chesapeake Bay vary, and it is likely that the original extent will never be known. The best estimates indicate that there were at least 200,000 acres of natural oyster reefs throughout the Chesapeake Bay.
- There are no natural oyster reefs left in the Chesapeake Bay today. What remains are the footprints of reefs. Every reef in the Chesapeake Bay has been either flattened or removed entirely by destructive fishing practices coupled with sedimentation.
- The “fossil” shells used in many oyster reef restoration projects are the bases of historic oyster reefs that are covered by sediments and no longer serve as oyster habitat. They are a limited resource and should be used wisely.