Marianas Trench Marine National Monument
Photograph by Paul Chesley
The United States' nearly 1,800 marine protected areas contain some of the country's most spectacular reefs, underwater archaeological sites, and most valuable commercial fisheries and tourist diving sites.
Ranging in size from less than one square mile (2.6 square kilometers) to over 139,797 square miles (362,073 square kilometers), the sites are located from the Arctic to the South Pacific, from Maine to the Caribbean, and as far west as the Philippine Sea.
The Marianas Trench Marine National Monument, established in 2009, and covering 95,216 square miles (246,608 square kilometers) of submerged lands, is one of the largest marine protected areas in the world. Within and adjacent to the Mariana Archipelago, the monument includes three areas of undersea mud volcanoes, more than 1,000 miles (1,609 kilometers) of the Mariana Trench, and the waters and submerged lands around some of the northern Mariana Islands.
Explorers and scientists are discovering strange and fantastic new species and habitats as they bridge this final frontier on Earth into the deep-sea. Advances in technology and engineering are opening up parts of the world once only dreamed of, while spotlighting the importance of conserving them as found, for future generations.
Photograph by Enric Sala
The snapper is one of the most abundant predators at the reef, second only to sharks. The large fish is a consummate hunter, eating everything from giant clams to sea urchins.
The waters here "are completely dominated by their predators," says National Geographic Fellow and marine ecologist Enric Sala. "Imagine the Serengeti with five lions per wildebeest. This is Kingman Reef."
Photograph by Claire Fackler
In the United States, 14 national marine sanctuaries, or underwater national parks, are part of the country's marine protected areas inventory and encompass 150,000 square miles (390,000 square kilometers).
The 1,470-square-mile (3,870-square-kilometer) sanctuary was designated in 1980.
Papahānaumokuākea Marine National Monument
Photograph by Tane Casserley/NOAA National Marine Sanctuaries
Underwater archaeologists search for sunken ships, airplanes, and other clues from the past in the Papahānaumokuākea Marine National Monument in Hawai'i.
Nearly 140,000 square miles (360,000 square kilometers)—100 times the size of Yosemite National Park—the Papahānaumokuākea sanctuary was designated in 2006.
The park stretches 1,200 miles (1,900 kilometers) through the Pacific Ocean along Hawai'i's northwestern islands. It is home to the endangered Hawaiian monk seal and several species found nowhere else on Earth.
Photograph by Medford Taylor
An icebreaker carves a path through Lake Superior's Thunder Bay, in Ontario, Canada.
The Thunder Bay area is home to more than a hundred shipwrecks and a rich shipping history. The 448-square-mile (1,160-square-kilometer) sanctuary was designated as federally protected because of its cultural resources.
humpback whale massachusetts
Photograph by Flip Nicklin/Minden Pictures
The 842-square-mile (2,180-square-kilometer) protected area is a productive fishing ground for cod, haddock, and flounder, as well as a popular whale-watching post.
A sanctuary designation prohibits activities such as sand and gravel mining, transferring petroleum products, and taking or harming marine mammals, birds, and turtles.
Olympic Coast National Marine Sanctuary
Photograph by Anne Keiser
Flattery Point juts into the waters of the Olympic Coast National Marine Sanctuary in Washington state.
The sanctuary—the size of Puerto Rico—hosts 29 species of marine mammals, including gray whales. It is one of the 14 U.S. national marine sanctuaries and 1,800 marine protected areas.
"Less than 5 percent [of the ocean] is explored, and a fraction of 1 percent is protected," says oceanographer and National Geographic Explorer-in-Residence Sylvia Earle. "The whole idea is to embrace protection for the ocean and not to kill the creatures that are there. You need to have real [sanctuary] in these areas, like in national parks."
Monterey Bay National Marine Sanctuary
Photograph by Chad King
A fish-eating anemone vacillates in Monterey Bay National Marine Sanctuary, California.
Designated in 1992 as a federally protected marine resource, the park has 276 miles (444 kilometers) of shoreline and 5,322 square miles (13,784 square kilometers) of ocean.
Park managers try to minimize the impacts of four major harbors plus urbanization and coastal development, as well as the impact of low frequency military testing. Testing may cause marine mammals, such as whales, to change their migratory routes and could disrupt feeding and mating.
Gray's Reef National Marine Sanctuary
Photograph by Flip Nicklin/Minden Pictures
A school of fish cruises by red coral in Gray's Reef National Marine Sanctuary, Georgia.
Covering 23 square miles (59 square kilometers) in the Atlantic Ocean, Gray's Reef is an unusual combination of rocky ledges and sandy flats that alternate to create a series of caves and cliffs. These features provide a platform for sponges, barnacles, sea fans, hard coral, sea stars, crabs, lobsters, snails, and shrimp.
Florida Keys National Marine Sanctuary
Photograph by Emory Kristoff
The islands in the Florida Keys span 126 miles (200 kilometers) and are home to the most extensive living coral reef in the United States, and the third largest on Earth.
Just south of the Florida peninsula, the Florida Keys National Marine Sanctuary covers 3,708 square miles (9,600 square kilometers).
The region receives more than four million visitors a year who come to dive, explore coral reefs and shipwrecks, and fish.
Beyond tourism, the Keys support a nearly 20-million-pound (9-million-kilogram) harvest of seafood and marine products annually. In an effort to protect the ecological and commercial resources in the park, the area was designated a national sanctuary in 1990.
- Ballard, Robert
- Bowermaster, Jon
- De Rothschild, David
- Doubilet, David
- Earle, Sylvia
- Frozen Seafood Benefits
- Goodman, Beverly
- Habitat Destruction
- Invasive Species
- Kristof, Emory
- Marine Food Chain
- Marine Pollution
- Nicklen, Paul
- Norman, Brad
- Ocean Overview
- Pristine Seas Expeditions
- Sala, Enric
- Seafood Decision Guide
- Seafood Substitutions
- Sea Level Rise
- Sea Temperature Rise
- Seaver, Barton
- Sustainable Seafood
- Thys, Tierney
- Tips to Save the Ocean
From the Channel
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