Region
United States
2,551
California
479
North Carolina
220
New York (State)
200
Great Lakes (North America)
159
Massachusetts
142
Great Lakes
125
Florida
118
India
106
Canada
85
Chesapeake Bay (Md. and Va.)
83
New Jersey
80
Europe
75
Atlantic Ocean
68
Chesapeake Bay Watershed
62
North America
61
China
59
Great Lakes Region
59
Great Lakes Region (North America)
59
Texas
55
Rhode Island
54
European Union countries
51
Illinois
48
Long Island Sound (N.Y. and Conn.)
48
Delta Region
45
Mexico
43
New York
41
Pennsylvania
40
Wisconsin
40
San Francisco Bay Area
38
Chesapeake Bay
37
Connecticut
37
Great Britain
37
New Hampshire
37
Michigan
36
West (U.S.)
36
Colorado
35
Maryland
35
Oregon
34
Minnesota
33
Australia
32
Developing countries
32
San Francisco Bay
32
Ohio
31
Asia
30
Colorado River Watershed (Colo.-Mexico)
30
Everglades
30
Idaho
30
Washington (D.C.)
30
Arizona
27
more ...