U.S. Fish and Wildlife Service

Data Element: ECOSYSTEM UNIT NUMBER

Name of Standard:  Ecosystem Unit Number

Description: One- and two-digit numbers that represent the ecosystem
unit boundaries of the United States, which are drawn primarily along
watershed boundaries.

Revision Date: October 18, 2005

Reason for Revision:  Ecosystems 30 and 32 have been renamed to coincide
with FWS Ecoregion names in the Southeast (Region 4)
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                                                                  LEAD
ECOSYSTEM                                         ECONUM          REGION
___________________________________________________________________________

NOT APPLICABLE                                      00               0
NORTH PACIFIC COAST                                 01               1          
KLAMATH/CENTRAL PACIFIC COAST                       02               1          
CENTRAL VALLEY OF CALIFORNIA/SAN FRANCISCO BAY      03               1          
SOUTHERN CALIFORNIA                                 04               1          
COLUMBIA BASIN                                      05               1          
INTERIOR BASIN                                      06               1          
LOWER COLORADO RIVER                                07               2          
GILA/SALT/VERDE RIVER                               08               2          
MIDDLE AND UPPER RIO GRANDE                         09               2          
LOWER RIO GRANDE                                    10               2          
PECOS RIVER                                         11               2          
EDWARDS PLATEAU                                     12               2          
EAST TEXAS                                          13               2          
TEXAS GULF COAST                                    14               2          
ARKANSAS/RED RIVERS                                 15               2          
SOUTHERN APPALACHIANS                               16               4          
UPPER COLORADO RIVER                                17               6          
PLATTE/KANSAS RIVERS                                18               6          
UPPER MISSOURI, YELLOWSTONE AND 		    19               6
 UPPER COLUMBIA RIVER         
MISSOURI MAIN STEM                                  20               6          
LOWER MISSOURI RIVER                                21               3          
MISSISSIPPI HEADWATERS/TALLGRASS PRAIRIE            22               3          
UPPER MISSISSIPPI RIVER/TALLGRASS PRAIRIE           23               3          
GREAT LAKES                                         24               3          
OZARK WATERSHEDS                                    25               3          
OHIO RIVER VALLEY                                   26               5          
LOWER MISSISSIPPI RIVER                             27               4          
TENNESSEE/CUMBERLAND RIVER                          28               4          
CENTRAL GULF WATERSHEDS                             29               4          
NORTHEAST GULF WATERSHEDS                           30               4          
ALTAMAHA WATERSHEDS                                 31               4          
NORTH FLORIDA                                       32               4          
SAVANNAH/SANTEE/PEE DEE RIVERS                      33               4          
ROANOKE/TAR/NEUSE/CAPE FEAR RIVERS                  34               4          
CARRIBEAN                                           35               4          
DELAWARE RIVER/DELMARVA COASTAL AREA                36               5          
HUDSON RIVER/NEW YORK BIGHT                         37               5          
CONNECTICUT RIVER/LONG ISLAND SOUND                 38               5          
GULF OF MAINE RIVERS                                39               5          
LAKE CHAMPLAIN                                      40               5          
CHESAPEAKE BAY/SUSQUEHANNA RIVER                    41               5          
PACIFIC ISLANDS                                     42               1          
ARCTIC ALASKA                                       43               7          
NORTHWEST ALASKA                                    44               7          
INTERIOR ALASKA                                     45               7          
SOUTHEAST ALASKA                                    46               7          
SOUTH CENTRAL ALASKA                                47               7          
BRISTOL BAY/KODIAK                                  48               7          
YUKON-KUSKOKWIM DELTA                               49               7          
BERING SEA/ALEUTIAN ISLANDS                         50               7          
BEAUFORT/CHUKCHI SEAS                               51               7          
NORTH PACIFIC/GULF OF ALASKA                        52               7          
SOUTH FLORIDA                                       53               4