For More Information

Office Information

Office of National Marine Sanctuaries

Complete list of ONMS websites

Fiscal Year Annual Reports

Background Information

podcast icon Diving Deeper: National Marine Sanctuaries (audio podcast)

Explore: National Marine Sanctuaries

Explore: Maritime Heritage

Office of National Marine Sanctuaries

whale tail

Did you know that around the U.S., there is a network of marine sanctuaries designed to preserve and protect some of our nation’s most valuable underwater places?

Managed by the Office of National Marine Sanctuaries, the National Marine Sanctuary System includes 13 sanctuaries and one national monument. Similar to the national parks on land, these underwater protected areas range in size from less than one square mile to more than 137,000 square miles. In total, the sanctuary system encompasses more than 150,000 square miles of U.S. ocean and Great Lakes waters.

You’ll find sanctuaries along the Pacific and Atlantic coasts of the continental U.S., as well as around the Hawaiian Islands, in American Samoa, and in the Great Lakes.

Sanctuaries protect thriving ecosystems like coral reefs and kelp forests, along with important breeding and feeding areas for marine life like whales, seabirds, sharks, and sea turtles. Within sanctuary boundaries lie countless links to our heritage, from historic shipwrecks to traditional Native American fishing grounds. Each sanctuary site is unique, with its own distinct collection of resources and management challenges.

Marine sanctuaries are natural classrooms, cherished recreational spots, valuable commercial industry sites, and places of significant maritime heritage. Research, monitoring, resource protection, and educational activities across the sanctuary system help us better understand and protect these special areas, so that we can enjoy them now and for years to come.

leaf