Sanctuaries
Four national marine sanctuaries contain coral reef ecosystems and one a tropical/temperate reef community. The sites range in size from 0.25 square miles to 3,674 square miles and are located in the Atlantic Ocean, Central and South Pacific Ocean, and the Gulf of Mexico. The diversity of locations and reef types makes this system unique and allows for valuable comparisons of reefs from differing biogeographic regions and of differing levels of use.
- Fagatele Bay: located 12 km southwest of Pago Pago Harbor on the southern most point of Tutuila, American Samoa, was formed by a collapsed volcanic crater and is surrounded by steep cliffs and volcanic rocks. Approximately 172 coral species have been recorded for the area.
- Florida Keys: Florida's coral reef tract extends from Fowey Rocks near Miami to the Dry Tortugas. The Florida reef tract is the most extensive living coral barrier reef system in North American waters and the third largest system in the world.
- Flower Garden Banks: located in the Northwestern Gulf of Mexico; over 200 km SSW of Galveston, Texas. Surficial hard substratum at the Flower Gardens is exclusively carbonate rock, constructed primarily by contemporary populations of coralline algae and corals. The surrounding water is clear, with visibility generally greater than 30 m and light penetrating well to 85 m.
- Gray's Reef: located approximately 34.2 km east of Sapelo Island, Georgia. Gray's Reef is one of the largest nearshore sandstone reefs in the southeast United States and, in terms of relief and marine life, is characteristic of live bottom reefs found offshore. It was likely formed 20,000 to 40,000 years ago during a period of dry climate when seawater in shallow areas evaporated.
- Hawaiian Islands: Atolls, barrier reefs, fringing reefs, patch reefs, and reef communities all occur in the Hawaiian Islands. A total of 47 coral species are found in Hawaiian waters. Common species include: Porities lobata, P. compressa, Pavona varians, Montipora capitata, and Pocillopora meandrina. P. compressa and M. capitata are endemic.