Based on data from 2008, there are an estimated 3 billion grams of oyster biomass in the Chesapeake Bay and its tidal tributaries.
Oysters are one of the most famous and recognizable species in the Chesapeake Bay. Learn why oysters are so important to the Bay’s ecosystem and how scientists are helping to restore their population.
Produced by Steve Droter
Stock Footage: University of Maryland Center for Environmental Science, Horn Point Oyster Hatchery
Music: “A Moment of Jazz” by Ancelin
Oysters are a valuable species because they improve water quality, provide habitat for aquatic life and contribute to the region’s economy.
Oysters filter water as they feed, which increases water clarity. It is estimated that at their historic population peak, oysters filtered all of the Bay’s water in less than one week. It takes about one year for the current population to do so.
Oysters have also constituted one of the Bay’s most valuable commercial fisheries for more than a century. Pollution, historic overharvesting, and the diseases MSX and Dermo have caused the oyster population to decline severely.
The goal is to achieve an oyster biomass of 31.6 billion grams. This would represent a tenfold increase in native oysters based on 1994 levels.
*Note: The historic data featured in this indicator changed from that reported in the 2008 assessment. Revised data from Virginia replaced the previously reported provisional data.
There is no statistically discernable trend away from the 1994 baseline. Oyster abundance remains at a very low level.
Between 1994 and 2008, goal achievement has averaged 9.61 percent and has ranged from 12.3 percent to 5.72 percent.
Short-term trend (10-year trend)
There is no statistically discernable trend. Oyster abundance remains at a very low level.
Between 1999 and 2008:
Change from previous year (2007-2008)
The information reported in this indicator:
Learn more about the Chesapeake Bay Oyster Population Estimation project, which provides the data used in this indicator.
The 2008 data are the most current data available. 2009 oyster abundance data will be available in 2011.
National Oceanic and Atmospheric Administration (NOAA)
Virginia Institute of Marine Science