Green Sturgeon (Southern DPS) polygon

Marine polygons were created using data from NOAA Office of Coast Survey for the shoreline along with Terra Logic bathymetry lines at the 110 meter depth contour. The final rule states that the 60 fathom depth line should be considered the most westerly boundary but the GIS producers were not aware of the availability of a reliable Pacific Coast continous 60 fathom bathymetry line at the time these data were created. Because the difference between the 110 meter depth and the 60 fathom depth is a minimal .1487 fathoms or .272 meters, the GIS producers along with the NMFS Critical Habitat Review Team (CHRT) decided for GIS purposes only to use the 110 meter bathymetric contour line.

The eastern boundary was created using the NOAA Electronic Nautical Charts (ENC) Shoreline Feature Class which represent the Mean Lower Low Water (MLLW) for the Pacific Coast. One continuous MLLW shoreline was created by merging the individual charts shoreline data. ENCs used to create the MLLW are listed below:

US3CA14M

US3CA15M

US3CA52M

US3CA69M

US3CA70M

US3CA85M

US3OR01M

US3OR02M

US3OR03M

US3WA01M

US3WA02M

US3WA03M

Only the mainland shoreline was used; islands were removed. The marine zone was clipped at numerous west coast estuary mouths to create a marine zone-only layer. Estuaries considered for critical habitat designation were clipped out based on COLREG lines as found on NOAA nautical charts.

The coastal bathymetry polygons did not extend to Strait of Juan de Fuca. To create a polygon for that area, a 10m DEM was used to create the 110m bathymetry line. Using the RasterToPolygon tool, a polygon was created for the area between the coastline and the 110m-depth bathymetry line.

The coastline to 110m marine zone for the Strait of Juan de Fuca was merged with the 110m marine zone for the rest of the Pacific Coast to create a single polygon describing marine waters within 110m depth from Monterey Bay, California, north to Cape Flattery, Washington, and east to include areas in the Strait of Juan de Fuca, Washington, to the U.S.-Canada boundary.

Edited the resulting polygon by dividing it into specific areas as defined by NMFS biologists developing the critical habitat designation.

Yolo and Sutter Bypass boundaries were modified according to where members of the NMFS critical habitat review team determined green sturgeon to be present.

Marsh areas were created using aerial imagery as a basemap and performing on-screen digitizing of polygons.

Navy areas excluded from designation were created through the input of coordinates, that were provided by the Department of Defense, and clipped out. Polygon filename: GreenSturgeonCHDepartmentofDefense.shp

(1) Mare Island U.S. Army Reserve Center, San Pablo Bay, CA;

(2) Strait of Juan de Fuca naval air-to-surface weapon range, restricted area, WA;

(3) Strait of Juan de Fuca and Whidbey Island naval restricted area, WA;

(4) Admiralty Inlet naval restricted area, Strait of Juan de Fuca, WA; and

(5) Navy 3 operating area, Strait of Juan de Fuca, WA.

Estuary polygons were selected and exported from NOAA's Medium resolution digital Vector Pacific Coast Shoreline. They represent the best available information to depict the specific estuarine areas occupied by the Southern DPS of green sturgeon. Estuary polygons were modified to depict areas downstream from the head of tide (where determinable). In the case where green sturgeon presence extended further upstream than where the estuary boundary was depicted, polyline data were used to depict head of tide and stream lines to the extent of tidal influence. The original estuary polygons were modified as needed to align the estuary-ocean boundary consistent with the Pacific Coast COLREG Demarcation lines.

Head of tide extents in estuaries were compiled (originally as point data - GreenSturgeonCHHeadofTide.shp) from visual inspection of 1:24,000 USGS topographic maps, aerial photographs, as well as various sources. For a listing of these sources and additional information regarding each of the head of tide locations and the sources or rationale for each point, see Appendix A in the final biological report for the final green sturgeon critical habitat rule (NMFS. 2009. Designation of Critical Habitat for the Threatened Southern Distinct Population Segment of North American Green Sturgeon: Final Biological Report, prepared by the National Marine Fisheries Service, Southwest Region, Long Beach, CA).

2009 source data converted to NMFS ESA critical habitat national standard 2020. Geometry was merged but boundaries were not edited. Attributes were edited. Metadata was compiled from 7 source files:

5 polygon files

GreenSturgeonCHBypassAreas.shp

GreenSturgeonCHEstuaries.shp

GreenSturgeonCHMarineCoastalZones.shp

GreenSturgeonCHMarshAreas.shp

GreenSturgeonCHDepartmentofDefense.shp

1 point file

GreenSturgeonCHHeadofTide.shp

1 line file

GreenSturgeonCHTribalExclusions.shp