Midway Atoll

Midway Atoll is a circular group of underwater reefs and three small islands in the North Pacific Ocean. Midway is part of the Northwestern Hawaiian Islands archipelago, a group of islets, atolls, and reefs that extend for about 1,500 miles (2,414 kilometers) northwest of the eight major Hawaiian Islands. Midway Atoll consists of about 134 square miles (347 square kilometers) of reef and 2.4 square miles (6.2 square kilometers) of land area. The atoll’s English name comes from its location midway in the Pacific, almost halfway between North America and Asia. In the native Hawaiian language, the atoll is known as Pihemanu (“loud din of birds”) Kuaihelani (“backbone of heaven”).

Midway Atoll has been a US territory since the nineteenth century. During World War II (1939–1945), it was the scene of the most decisive naval battle in the Pacific theater. The American victory over the Japanese at Midway is often credited with turning the tide of the war in favor of the United States. In the twenty-first century, Midway Atoll is part of one of the largest wildlife refuges in the world.

Overview

An atoll is a ring-shaped island formed from coral reefs, small islands, or islets. Midway Atoll is part of the Hawaiian Islands, a chain of 137 islands and smaller islets in the Pacific Ocean. The Hawaiian Islands sit on a “hot spot” in the Pacific, where molten rock wells up from inside Earth’s crust. As the molten rock cools, it builds up, eventually forming mountains that rise above the water line as islands. As the crust slowly moves over the hot spot, new islands are formed. Midway was born from a volcanic eruption about twenty-eight million years ago, making it the second oldest in the chain. Over the years, the mountain slowly eroded, eventually being whittled down to three small islets and a coral reef.

Midway’s circular outer coral reef is about 5 miles (8 kilometers) in diameter. Sand Island is the largest of the atoll’s three islands, with an area of 1.7 square miles (4.4 square kilometers). Eastern Island has an area of 0.6 square miles (1.5 square kilometers), and Spit Island is only .02 square miles (.05 square kilometers) in size.

The first people to visit Midway were Polynesian seafarers who arrived hundreds of years ago. Although they did not stay, historical accounts mention that they sighted seabird-covered islands in the vicinity of Midway. The first Westerner to spot Midway was American ship captain N.C. Brooks in 1859. Eight years later, Naval Captain William Reynolds took possession of the atoll for the United States.

To combat poachers, President Theodore Roosevelt placed the atoll under the control of the US Navy in 1903. That same year, Midway became the final station for a global telegraph system that carried the first message around the world. In the 1930s, Pan American Airways built the first airstrip on Midway, which became a refueling stop for the airline’s seaplanes. In 1940, the US Navy began building a military airbase on the atoll. It was completed in August 1941.

On December 7, 1941, the Japanese Navy staged a surprise attack on the US Pacific fleet stationed at Pearl Harbor in Hawaii. The attack killed more than 2,400 Americans and severely damaged more than twenty ships, including eight battleships. Despite the losses, the United States still had a formidable naval force, including three aircraft carriers, which were not at Pearl Harbor on the day of the attack. This attack led to the United States declaring war on the Axis Powers—Japan, Germany, and Italy—and officially entering World War II.

For the first several months of the war, Japan was the dominant power in the Pacific Theater and quickly overpowered US territories in the Philippines and elsewhere, threatening both Hawaii and Australia, a key US ally. The Japanese wanted to finish off the US fleet and cement their military dominance, so they devised a trap to lure the US aircraft carriers to Midway Atoll. The plan was to attack Midway and take the island. When the US ships showed up to defend the island, four Japanese aircraft carriers would be lying in wait to strike a deciding blow. However, Navy intelligence analysts were able to decode the Japanese communications and knew of the Midway invasion in advance.

When the Japanese attack began on June 4, 1942, a US Navy force was at Midway to take them on. As the Battle of Midway raged, its outcome was in doubt, as both the Japanese and the Americans struggled to gain an advantage. In the end, US pilots were able to hit and destroy all four Japanese aircraft carriers. The victory was the major turning point in the Pacific war, as it was the Japanese Navy and not the US Navy that was left crippled after the battle. The victory also gave the American Navy increased confidence that it could defeat the Japanese, who up to that point had the stronger naval force. From that point on, Japan was on the defensive until its final surrender in August 1945.

Topic today

Midway Atoll housed a military base until 1993. Three years later, it was transferred to the control of the US Fish and Wildlife Service and made a wildlife refuge. The Midway Atoll Wildlife Refuge is part of the larger Papahānaumokuākea Marine National Monument. The 582,578 square mile (1.5 million square kilometer) protected area is a United Nations World Heritage site and one of the largest wildlife refuges in the world.

The Midway Atoll Wildlife Refuge is home to more than 250 species of fish and numerous mammal species, including monk seals, spinner dolphins, and green sea turtles. However, the atoll is best known for its bird population, boasting nineteen species that number more than two million. Among the species on the atoll are three rare species of albatross and the endangered Laysan duck. In the early twentieth century, the Laysan duck was so close to extinction that only one female remained. The population rebounded, and in 2005, forty-two ducks were relocated to Midway to start a new colony. By the early 2020s, following additional translocation efforts to Kure Atoll, the global wild population increased to an estimated 800 to 1,000 individuals, marking a rare conservation success for an island-endemic species once reduced to a single surviving female.

During its days as a US Navy base, Midway Atoll had a population of about five thousand people. In the twenty-first century, it is home to about forty workers with the US Fish and Wildlife Service. Much of the World War II–era military infrastructure remains on Midway Atoll in the twenty-first century, reflecting its long history as a strategic US naval outpost. Henderson Field, originally constructed as a military airstrip, operate as a designated emergency landing site for trans-Pacific flights, particularly for aircraft experiencing distress while crossing remote sections of the ocean. Although regular commercial service ended decades ago, the runway is maintained by the US Fish and Wildlife Service in cooperation with the Federal Aviation Administration (FAA) to support emergency aviation needs, conservation logistics, and limited governmental access to the atoll. The presence of this infrastructure underscores Midway’s dual legacy as a military landmark and a protected wildlife refuge. In 2000, the Battle of Midway National Memorial was erected on the atoll, marking the site of the battle and honoring those who fought and died there.

The Midway Atoll is a vulnerable place. When an earthquake struck the eastern coast of Japan in March 2011, it triggered a subsequent tsunami that affected nations in the Pacific Ocean. The 2011 Tōhoku earthquake and tsunami caused significant damage to the bird populations at the Midway Atoll Wildlife Refuge, killing over 100,000 nesting seabirds due to the large waves. Further, the Midway Atoll Wildlife Refuge is at significant risk due to rising sea levels caused by global climate change. 

Midway Atoll continued to face significant environmental risks into the 2020s. In January 2022, the US Fish & Wildlife Service reported that rising sea levels and increasingly intense storms placed growing pressure on the atoll’s low-lying infrastructure and fragile wildlife habitats. These concerns were illustrated in July 2025, when tsunami-driven wave surges caused by an earthquake off the coast of Russia produced wave heights of up to 1.8 meters (about 6 feet) at Midway, prompting precautionary measures on the atoll and across the Hawaiian Islands. These events highlighted the escalating vulnerability of Midway Atoll to climate-related ocean hazards and extreme weather.

Bibliography

Burgoyne, Walt. “Midway Before and After.” National WWII Museum, 30 May 2020, www.nationalww2museum.org/war/articles/midway-wwii-pacific-theater. Accessed 21 May 2024.

“Chronology.” MidwayIsland.com, April 2021, www.midway-island.com/history/chronology-of-events/. Accessed 11 July 2021.

Hone, Thomas C. The Battle of Midway: The Naval Institute Guide to the U.S. Navy’s Greatest Victory. Naval Institute Press, 2016.

"Laysan Duck." US Fish and Wildlife Service, www.fws.gov/species/laysan-duck-anas-laysanensis. Accessed 20 Oct. 2025.

“Midway Atoll.” Papahanaumokuakea Marine National Monument, 30 July 2020, www.papahanaumokuakea.gov/visit/midway.html. Accessed 21 May 2024.

“Midway Atoll National Wildlife Refuge and Battle of Midway National Memorial.” U.S. Fish & Wildlife Service, 4 June 2021, www.fws.gov/refuge/midway_atoll. Accessed 21 May 2024.

“Midway Atoll National Wildlife Refuge (NWR).” ArcGIS, 2021, www.arcgis.com/apps/MapJournal/index.html?appid=1c7fa9f06c864e529aaa6f1fd422ca71. Accessed 11 July 2021.

O’Brian, Bill. “The Midway Atoll You Might Not Know.” U.S. Fish & Wildlife Service, 25 Mar. 2019, www.fws.gov/refuges/features/The-Midway-Atoll-You-Might-Not-Know.html. Accessed 21 July 2024.

Polan, Jason, and Michele Berger. “Tsunami Takes Toll on Albatross Populations.” National Audubon Society, 22 Mar. 2011, www.audubon.org/news/tsunami-takes-toll-albatross-populations. Accessed 21 May 2024.

Winn, Krystal. "Tsunami Summary Report." Friends of Midway Atoll, 14 Aug. 2025, friendsofmidway.org/tsunami-summary-report/

“World War II Facilities at Midway.” National Park Service, 8 Apr. 2021, www.nps.gov/articles/world-war-ii-facilities-at-midway.htm. Accessed 11 July 2021.