Region
United States
11
North America
4
Caribbean Area
3
Latin America
3
Mexico, Gulf of
3
Blackwater National Wildlife Refuge (Md.)
2
California
2
Colorado
2
Maryland
2
Pacific Coast (North America)
2
Alaska
1
Alcona County
1
America
1
Antarctica
1
Arctic National Wildlife Refuge
1
Arctic National Wildlife Refuge (Alaska)
1
Atlantic Coast (North America)
1
Cambridge
1
Cambridge Region
1
Colorado River Valley (Colo.-Mexico)
1
Eastern Hemisphere
1
Huron, Lake (Mich. and Ont.)
1
Loma, Point
1
Long Island
1
Louisiana
1
Mexico
1
Michigan
1
Mississippi River Watershed
1
Naval Base Coronado
1
New Mexico
1
New York (State)
1
Ontario, Lake (N.Y. and Ont.)
1
Presque Isle County
1
Rio Grande (Colo.-Mexico and Tex.)
1
South America
1
Southern States
1
Southwest, New
1
Western Hemisphere
1