||Oak Ridge National Lab., TN. Environmental Sciences Div.;Environmental Protection Agency, Washington, DC. Office of Marine and Estuarine Protection.;Department of Energy, Washington, DC.;Martin Marietta Energy Systems, Inc., Oak Ridge, TN.
The project seeks to develop strategies and priorities for arresting habitat deterioration and restoring lost habitats in estuaries through identification of critical zones for maintaining living resources. It uses as an example one representative and important estuarine species, the striped bass (Morone saxatilis). Data on summer water temperatures, dissolved oxygen concentrations, and striped bass distribution in Chesapeake Bay and Albemarle Sound, North Carolina, were evaluated to determine/establish if critical zones existed for maintenance of populations. Criteria for habitat suitability for adults and subadults were those identified in freshwater reservoirs (<25C and >2 mg/l dissolved oxygen). In Chesapeake Bay, two key areas were identified: (1) a zone of residual cool water (<25C) in the vicinity of the William Preston Lane, Jr. Memorial Bridge (Bay Bridge) near Annapolis, where striped bass subadults and adults congregate in summer, and (2) a shallow sill near the mouth of the Rappahannock River, where warm surface waters (>25C) in summer impinge on the bottom and may block egress of striped bass subadults and adults from the bay. Increasing anoxia in the bay in recent years, especially in the residual cool water, has reduced the amount of suitable habitat available. The Bay Bridge and sill areas are suggested as high-priority zones for pollution monitoring and control.