Over 41 percent of U.S. marine waters are protected to some degree

Elkhorn Slough

MPAs are areas where natural or cultural resources are given greater protection than the surrounding waters. In the United States, MPAs span a range of habitats including the open ocean, coastal areas, inter-tidal zones, estuaries, and the Great Lakes.

There are over 1,700 marine protected areas (MPAs) in the United States established by federal, state, and territorial governments. These areas cover 41 percent of U.S. marine waters and vary widely in their purpose, legal authorities, managing agencies, and level of protection. MPAs that are focused on the protection of ecosystem, biodiversity, and cultural resources cover about eight percent of marine waters.

Although MPAs are found in every region of the United States, the West Coast, including California, Oregon, and Washington, has the highest number of MPAs.  However, the region with the largest area of MPAs is the Pacific Islands. This is because of the designation of the Papahānaumokuākea Marine National Monument, which is one of the largest marine conservation areas in the world.

For more information:
MPAs: Evolving Efforts to Manage Marine Resources, NOAA 200th Anniversary Web Site
Marine Protected Areas Center
Marine Protected Areas Virtual Library
Office of Ocean and Coastal Resource Management
MPA Case Studies
Diving Deeper: Marine Protected Areas