Region
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Puget Sound Region
1
Quivira National Wildlife Refuge
1
Quivira National Wildlife Refuge (Kan.)
1
Red River of the North
3
Rio Grande (Colo.-Mexico and Tex.)
1
Rio Grande Valley (Colo.-Mexico and Tex.)
1
Rio Hondo Watershed
1
Rotterdam
1
Sacramento River (Calif.)
2
San Bernardino County
1
Sandy Hook
1
Santa Barbara County
2
Santa Cruz River Watershed
1
Santa Cruz River Watershed (Ariz. and Mexico)
1
Santa Fe Group
1
Savannah River Site
3
Schuylkill River Watershed
1
Seattle
1
Selway-Bitterroot Wilderness
1
Selway-Bitterroot Wilderness (Idaho and Mont.)
1
Shell Lake (Lake)
1
Shenandoah River (Va. and W. Va.)
1
Sheyenne River
2
Sierra Nevada
1
Sierra Nevada (Calif. and Nev.)
1
Sinclair Inlet
1
Skagit County
1
Skagit River Watershed
1
Skagit River Watershed (B.C. and Wash.)
1
Skunk Creek (S.D.)
1
Slovenia
2
Snake River, South Fork
1
Snohomish County
1
Solar system
1
Souris River
1
Souris River Valley
1
South Carolina
6
South Dakota
4
Southern States
2
Spain
15
Spirit Lake
1
Suffolk County
1
Tahoe, Lake, Watershed (Calif. and Nev.)
1
Taiwan
6
Tarrant County
1
Tennessee
3
Texas
4
Thurston County
1
Trinity River, West Fork
1
Trout Lake (Vilas County)
1
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