| Sanctuary |
Designated |
Boundary Expansion? (year) |
Notes |
| Monitor |
Feb 1975 |
No |
- Designation by NOAA to protect one of the most important Civil War ironclad shipwrecks from potential salvage. |
| Key Largo |
Jan 1976 |
No |
- Designation by NOAA to protect the portion of barrier reef beyond state waters of John Pennekamp Coral Reef State Park.
- The Florida Keys National Marine Sanctuary subsumed this marine sanctuary in 1990. |
| Channel Islands |
Oct 1980 |
Yes (2007) |
- Designation by NOAA to protect a confluence of warm and cold water currents with a great abundance and variety of marine life.
- Expansion by NOAA: Very minor increase in the area associated with the addition of marine reserves. |
| Gulf of the Farallones |
Jan 1981 |
No |
- Designation by NOAA to protect an extensive marine habitat and bird colonies. |
| Looe Key |
Jan 1981 |
No |
- Designation by NOAA to protect the unusual and highly important spur and groove reef system.
- The Florida Keys National Marine Sanctuary subsumed this marine sanctuary in 1990. |
| Gray's Reef |
Jan 1981 |
No |
- Designation by NOAA to protect a prime example of South Atlantic hard/live bottom coral habitat. |
| Fagatele Bay |
Apr 1986 |
Yes (2012) |
- Designation by NOAA to protect an example of a South Pacific, tropical, fringing coral reef ecosystem.
- Expansion by NOAA: Addition of five units, including the Rose Atoll Marine National Monument, and renaming of the sanctuary as the National Marine Sanctuary of American Samoa. |
| Cordell Bank |
May 1989 |
No |
- Designation by NOAA to protect an area of bank where upwelling of nutrient-rich deep water supports a flourishing ecosystem. |
| Florida Keys |
Nov 1990 |
Yes (2001) |
- Designated by Congress in response to a series of large vessel groundings in 1989, it protects the largest coral barrier reef ecosystem in the US.
- Expansion by NOAA: Addition of valuable coral reef habitat added to the west of the original boundary (Tortugas Bank and Sherwood Forest Tortugas Ecological Preserve).
|
| Flower Garden Banks |
Jan 1992 |
Yes (1996) |
- Designation by NOAA to protect important coral reefs on the salt domes of the northwestern Gulf of Mexico.
- Expansion by Congress: Addition of Stetson Bank. |
| Monterey Bay |
Sep 1992 |
Yes (2008) |
- Designation by NOAA to protect a variety of habitats including shores, kelp forests, and an underwater canyon.
- Expansion by NOAA: Davidson Seamount was added as an example of offshore seamount with special geological and ecological value. |
| Stellwagen Bank |
Nov 1992 |
No |
- Designation by Congress to protect the primary summer feeding grounds of the endangered North Atlantic right whale, and other important marine features. |
| Hawaiian Islands Humpback Whale |
Nov 1992 |
No |
- Designation by Congress to protect calving and breeding grounds of the endangered North Pacific humpback whale. |
| Olympic Coast |
May 1994 |
No |
- Designation by NOAA as a representative marine and near-shore habitat of the Pacific Northwest, adjacent to the protected Olympic National Park. |
| Thunder Bay |
Jun 2000 |
No |
- Designation by NOAA to protect the collection of nationally significant historic shipwrecks in an area of Lake Huron known as Shipwreck Alley. |
| Papahānaumokuākea
Marine National Monument |
Jun 2006 |
No |
- Papahānaumokuākea was established by Presidential Proclamation 8031 on June 15, 2006 under the authority of the Antiquities Act (16 U.S.C. 431-433) to protect an exceptional array of natural and cultural resources. |