Sentinel sites have been established in Maryland tributaries of the Chesapeake Bay to facilitate monitoring of oyster populations at specific locations over time. The term "sentinel site" is used to describe a monitoring station for which long-term monitoring data are available. Monitoring at the sentinel sites is being performed by the Maryland Department of Natural Resources. The monitoring program was established to track oyster population and disease levels baywide. Replenishment and restoration activities are in progress near many of the existing sentinel sites.
Sentinel sites in Chesapeake Bay tributaries in Maryland waters were assigned to the following basin categories: the Chester River, Eastern Bay, Choptank River, Little Choptank River, Tangier Sound, the Potomac River, Patuxent River, and the Maryland portion of the Chesapeake Bay mainstem. These basins are shown on the map below.
Oyster populations at sentinel sites are evaluated using annual dredge survey data. All of the sentinel site locations are sampled annually by scientists from the Maryland Department of Natural Resources. Two half-bushel samples are collected. Data for these stations is reported using oyster counts and individual oyster shell measurements..
Annual estimates of oyster populations at sentinel sites within Maryland's basins made with these data categories are available for:
Annual estimates of oyster population numbers and biomass are useful for describing trends in at selected Maryland sentinel sites over time. Graphs of estimated oyster numbers and oyster biomass in the period 1994-2002 are available for: