Región
United States
17
Great Britain
10
Africa
5
China
4
Developing countries
4
Ireland
4
Asia
3
India
3
Africa, Southern
2
Finland
2
Japan
2
Arizona
1
Canada
1
East Asia
1
Egypt
1
England
1
Foreign countries
1
Former communist countries
1
Israel
1
Italy
1
Latin America
1
Mekong River Region
1
Middle East
1
Monumento Natural Marino Archipiélago Cayos Cochinos (Honduras)
1
Nile River Watershed
1
Pacific Area
1
Southwestern States
1
Turkey
1
Vietnam
1
Wales
1