Place
- Iceland10
- Israel10
- Jackson Demonstration State Forest (Calif.)10
- Lake County (Calif.)10
- Liberia10
- Machias Bay (Me.)10
- Madagascar10
- Malawi10
- Mauritania10
- Mexico City (Mexico)10
- Mono County (Calif.)10
- Narragansett Bay (R.I.)10
- Polar regions10
- Angola9
- Beijing (China)9
- Block Island Sound (R.I.)9
- Blue Hill Bay (Me.)9
- Central America9
- Chicago (Ill.)9
- Congo9