Environment Planet Earth Where Are Earth's Largest Nature Reserves? By Angela Nelson Angela Nelson Twitter Writer Boston University Angela Nelson is a Pulitzer Prize-winning digital editor and storyteller who covered a variety of general interest stories on MNN (now part of Treehugger) from 2014-2019. Learn about our editorial process Updated November 27, 2020 Photo: National Park Service, Alaska Region/Wikimedia Commons Share Twitter Pinterest Email Planet Earth Outdoors Weather Conservation The United States has some massive nature reserves. The Wrangell-St. Elias National Park in Alaska, for example, is the biggest in the country at more than 20,587 square miles — an area so large that six Yellowstone Parks could fit in there. Death Valley National Park — the largest national park in the Lower 48 — straddles California and Nevada, covering more than 5,000 square miles. It could take days or weeks to see everything in either one of those sprawling parks. But on a global scale, they pale in comparison to other nature reserves. You could fit 29 Wrangell-St. Elias National Parks within the largest marine reserve in the world, for example. Read on for more mind-blowing facts and figures about the world's eight largest nature reserves. 1 of 8 Ross Sea Marine Reserve Photo: AndreAnita/Shutterstock.com The Ross Sea in Antarctica is home to the world's largest marine reserve, covering 598,000 square miles — an area twice the size of Texas — in the Southern Ocean. It's also one of the newest nature reserves, established in October 2016 by the Commission for the Conservation of Antarctic Marine Living Resources, a group of 24 countries that oversees the water around the continent. The Ross Sea is also known as the "Last Ocean" because it's one of the last remaining stretches of ocean that has not been harmed by humans or damaged extensively by overfishing, pollution or invasive species, according to the Antarctic and Southern Ocean Coalition. The extremely remote area is inaccessible by boat most of the year, which helps preserve it, though the rising demand (and price) for seafood and the low cost of fuel may tempt some fishermen to brave the journey. National Geographic reports: "Its nutrient-rich waters are the most productive in the Antarctic, leading to huge plankton and krill blooms that support vast numbers of fish, seals, penguins, and whales. Some 16,000 species are thought to call the Ross Sea home, many of them uniquely adapted to the cold environment." 2 of 8 Natural Park of the Coral Sea Photo: Seaphotoart/Shutterstock A close second in size to the Ross Sea Marine Reserve is the Natural Park of the Coral Sea, which protects 501,930 square miles of marine ecosystems around New Caledonia, a French territory off the coast of Australia. It was established in 2014 by the government of New Caldonia, even though some of the lagoons and coral reefs were already protected as a UNESCO World Heritage site. The waters are a sanctuary for sharks, whales and turtles, according to Conservation International, and the circular reefs extend for more than 600 miles. The IUCN says the Coral Sea is home to 25 species of marine mammals, 48 shark species, 19 species of nesting birds and five species of marine turtles. Though environmentalists laud the sanctuary, questions remain about the semiautonomous nation's ability to police the area. As Time magazine reports, "New Caledonia, however, has no navy of its own and relies on a handful of French ships to patrol an area twice the size of Texas and three times the size of Germany. What, in the end, is the meaning of its marine sanctuary if it cannot police it?" 3 of 8 Pacific Remote Islands Marine National Monument Photo: U.S. Fish and Wildlife Service/flickr The Pacific Remote Islands Marine National Monument, which is southwest of Hawaii, was first established in 2009 under President George W. Bush, and in 2014 President Barack Obama expanded it to 490,000 square miles — an area six times its original size. The monument includes three islands (Howland, Baker and Jarvis), three atolls (Johnston, Wake and Palmyra) and Kingman Reef. Many threatened and endangered species call these waters home, including the green and hawksbill turtle, pearl oyster, giant clams, reef sharks, coconut crabs, groupers, humphead and Napoleon wrasse, bumphead parrotfish, dolphins and whales, according to the National Oceanic and Atmospheric Administration (NOAA), which manages the area along with the U.S. Fish and Wildlife Service. 4 of 8 Papahānaumokuākea Marine National Monument Photo: Claire Fackler, CINMS, NOAA/Wikimedia Commons Another joint effort from President Bush and President Obama is the Papahānaumokuākea Marine National Monument, the largest contiguous fully protected conservation area in the United States, which was created in June 2006 and expanded in 2016 to encompass 582,578 square miles in the Pacific Ocean near Hawaii. The extensive coral reefs found in this section of the Pacific Ocean are home to more than 7,000 marine species, one quarter of which are found only in the Hawaiian Archipelago, according to the monument's website. And 14 million seabirds from 22 species breed and nest there. Papahānaumokuākea, which is also a UNESCO World Heritage site, is important not only to marine life, but to native Hawaiians, as significant cultural sites are contained within the monument, such as the heiau shrines on the islands of Nihoa and Mokumanamana, which are listed on the National and State Register for Historic Places. 5 of 8 South Georgia Marine Protected Area Photo: evenfh/Shutterstock The South Georgia and the South Sandwich Islands are a U.K. Overseas Territory about 800 miles southeast of the Falkland Islands in the South Atlantic Ocean. The remote chain of small volcanic islands are part of a Marine Protected Area (MPA) of more than 413,000 square miles. According to the government website, more than half of South Georgia Island is permanently ice covered, so there are no permanent residents. But the area is important because it is a "relatively pristine and rich environment that sustains major populations of seabirds and marine mammals including globally threatened species, like the iconic wandering albatross." Much like the Ross Sea, the waters around South Georgia Island support a large biomass of krill, and many marine predators depend on that supply. 6 of 8 Greenland National Park Photo: Chris Howey/Shutterstock Greenland has bragging rights to the largest national park in the world at 375,000 square miles. As Conde Nast Traveler points out, "That’s bigger than Pakistan, bigger than Venezuela, bigger than France. In fact, there are only 30 nations on Earth larger than this single park." But Greenland National Park, in the northeast portion of the Arctic country, isn't a traditional national park like Yellowstone or Acadia. No people live in the area, and the only people with regular access are sealers and whalers from the nearby town of Ittoqqortoormiit (one of the most remote towns in the world), according to the park website. "During a typical winter, you’ll find a dozen park rangers and a handful of weather scientists in Northeast Greenland National Park, along with their 110 dogs. That’s it, in an area about the size of the U.S. eastern seaboard," Conde Nast reports. The park gets about 500 visitors a year, mostly on cruises to the Arctic. Tourists may have the opportunity to see giant walrusses, polar bears, caribou, musk oxen or foxes, but you need a permit from the Ministry of Nature & Environment to go. 7 of 8 Chagos Marine Protected Area Photo: Anne Sheppard/Wikimedia Commons The Chagos Archipelago is a group of seven atolls which form 55 tiny islands in the Indian Ocean about 310 miles south of the Maldives. The 397,678-square-mile area was designated as a marine reserve in 2010 because it contains the world’s largest coral atoll, The Great Chagos Bank, along with some of the planet's healthiest reef systems and cleanest water, according to the Chagos Conservation Trust. Chagos has eight times more reef fish than anywhere else in the world, according to the London Zoo. It also supports a diverse array of sharks — coastal reef, shortfin mako, blue, ocean whitetip and whale sharks — and reef manta rays. The London Zoo says it's also a big tuna spot, with yellowfin, bigeye, skipjack, albacore and dogtooth swimming in the rich waters. 8 of 8 Ahaggar National Park Photo: Houcine.lk/Wikimedia Commons Algeria's Ahaggar National Park in the Sahara covers more than 173,000 square miles, with the most dominant feature being the Ahaggar Mountains, also known as the Hoggar Mountains. The jagged landscape abuts Tamanrasset, an oasis city and capital of Tamanrasset Province in southern Algeria. Algeria's official website says a number of animal species that have died off in other parts of the Sahara — including Saharan cheetahs, Dorcas gazelles and Barbary sheep — are still found in the park because the climate in the park is less extreme than in most other areas of the desert. And this tour company says visitors also have the opportunity to see genets, mongoose, leopards, golden jackals, Ruppell’s foxes, sand cats, fennecs, addax, dama gazelles and the endangered painted hunting dog.