work, using estuarine salinity zones based on the 

 National Estuarine Inventory (NEI), was adopted 

 (NOAA 1985). Figure 2 summarizes the major steps 

 taken to collect and organize this information. The 

 initial steps were to select the estuaries and species for 

 study. 



Selection of estuaries. Estuaries in each region were 

 selected from the National Estuarine Inventory (NED 

 Data Atlas-Volume I (NOAA 1985a). Additional estu- 

 aries were added after discussions with regional re- 

 searchers. The 122 selected estuaries are listed in 

 Table 2 (their locations within each region are shown 

 in Figures 6, 8, 10, 13, and 16). 



Data on the spatial and temporal distributions of 

 species were compiled for the tidal fresh (0.0-0.5 parts 

 per thousand (ppt)), mixing (0.5-25.0 ppt), and seawa- 

 ter (> 25 ppt) zones delineated for each estuary in the 

 NEI. Many of the estuaries within each region contain 

 all three salinity zones, but for the purposes of this 

 study, some zones are considered to be absent. For 

 example, the tidal Potomac River in Maryland has no 

 seawater zone, and Morro Bay in California has no 

 tidal fresh zone. Salinity zones that are only season- 

 ally present or are extremely small (<1 km 2 ) were 

 generally omitted from this large-scale assessment 

 (NOAA 1985a). 



The NEI is now being superceded by NOAA's Na- 

 tional Coastal Assessment and Data Synthesis Frame- 

 work (CA&DS), which integrates national data sets 

 for 138 estuaries within a spatial framework with 



analytical capabilities (Orlando 1999). CA&DS is a 

 national and regional-scale data base and mapping 

 analysis system that provides a capability to access, 

 synthesize, assess and apply nationwide data sets to 

 priority coastal issues, such as estuarine eutrophica- 

 tion, habitat loss, coastal monitoring, and sustainable 

 coastal communities. The spatial framework includes: 



• Spatial geographies for 150 estuaries, major rivers, 

 and coastal offshore areas. 



• National data sets for coastal resources (including 

 ELMR), environmental quality, and socio-economic 



activities. 



• An interactive web-based data access and mapping 

 system that allows users to view, conduct compara- 

 tive analyses, and download information. 



Selection of species. ELMR staff biologists used the 

 following four criteria, together with data availabil- 

 ity, to select species for inclusion in each regional 

 ELMR data base: 



• Commercial value — determined by review of catch 

 data and value statistics from NMFS and state agen- 

 cies (NOAA 1992a, NOAA 1992b). 



• Recreational value — determined by relative im- 

 portance in recreational fisheries that may or may not 

 be commercially exploited. Recreational species were 

 determined by consulting regional experts and NMFS 

 reports (Essig et al. 1991, VanVoorhees et al. 1992). 



National 



Estuarine 



Inventory 



Data 



122 



Estuaries 



Compile 



Estuary 



Information 



Prepare 



Species/Estuary 



Data Sheets 







Peer Review: 

 Data Verification 



Microcomputer 

 Data Base 



Develop 

 Life History 

 Summaries 



Outputs 



Spatial 

 Distribution 



Temporal 

 Distribution 



Relative 

 Abundance 



Data 

 Reliability 



Figure 2. Major steps to complete the National ELMR study, 1985-1994. 



