Gulf Sturgeon (line)

This data set was created using ArcView 3.2a

The process steps for creating the final Gulf sturgeon riverine critical habitat units were:

1. NHD arc and route.reach files were brought into the view for each basin covered by the final critical habitat.

2. Records in the route.reach files were selected by querying on the name field. Additional unnamed records (mainly distributaries) were selected within the view using the selector tool.

3. Records in the arc files were selected using the "Select by theme..." command, choosing all records that were completely within the route.reach files. The selected records were visually checked to ensure that only river centerlines were included.

4. Using the X-Tools extension "merge themes" command, all selected records from the NHD arc files were combined into the stg_ch_final.shp file.

5. Distributaries that were not included in the NHD arc files but were included in the Federal Register maps or DeLorme state gazetteers were added to the shapefile with on-screen digitizing.

6. Using the narrative unit descriptions from the Federal Register, some arcs were spilt and parts were removed. This only occurred in units where the highest river reach included stopped at a road crossing. The roads layer used to determine this stopping point is from the ESRI Sample Data and Maps, CD Volume 5, Southern U.S., August 1999.