Region
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Nevada
4
New Mexico
2
Nez Perce National Historical Park
1
Noatak National Preserve (Alaska)
1
North America
2
North Cascades (B.C. and Wash.)
2
North Cascades National Park
1
North Cascades National Park (Wash.)
1
Northwest, Pacific
4
Oceania
1
Ohio
1
Olympic National Park
1
Olympic National Park (Wash.)
1
Oman
1
Ontario, Lake (N.Y. and Ont.)
1
Oregon
9
Ouachita National Forest (Ark. and Okla.)
1
Ozark National Forest (Ark.)
1
Pacific Islands (Trust Territory)
1
Pacific Ocean
1
Pea Ridge National Military Park
1
Pea Ridge National Military Park (Ark.)
1
Pennsylvania
2
Persian Gulf Region
2
Phoenix
1
Piceance Creek Basin
1
Pima County
1
Polar regions
1
Prince William Sound
2
Puget Sound
1
Puget Sound (Wash.)
1
Qatar
1
Quivira National Wildlife Refuge
1
Quivira National Wildlife Refuge (Kan.)
1
Racine County
1
Reserva de Biosfera Seaflower (Colombia)
2
Rocky Mountain National Park
1
Rocky Mountain National Park (Colo.)
1
Rocky Mountains
8
Rocky Mountains Region
1
Sacramento Mountains
1
Salt River (Gila County and Maricopa County, Ariz.)
1
Salton Sea
8
Salton Sea (Calif.)
6
San Francisco Bay Area
6
San Francisco Bay Area (Calif.)
6
Santa Cruz River (Ariz. and Mexico)
1
Selenga River Watershed (Mongolia and Russia)
1
Serengeti National Park (Tanzania)
1
Serengeti National Park Region
2
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