Rabbit Island’s Buried Memory: How Tourism Policies Obscure Ōkunoshima’s Dangerous Legacy

By Dmitrii Dunichev

Abstract
Ōkunoshima, a small island in Hiroshima Prefecture, is widely known as “Rabbit Island,” a tourist destination famous for its large population of rabbits. However, its history as a chemical weapons production site during World War II remains largely overshadowed, while the island’s toxic legacy continues to pose health risks. This article examines the “forgetting” of the island’s chemical weapons legacy, the role of tourism policies in shaping its public image, and the challenges of preserving its memory. Despite efforts by local peace activists, the dominant tourism narrative emphasizes recreation over historical awareness, leaving the broader public oblivious to the ongoing environmental and health dangers. The case of Ōkunoshima highlights the tension between economic interests, historical accountability, and human security in Japan’s memory politics.

Keywords: Ōkunoshima, Memory, Chemical Weapons, World War II

Ōkunoshima is a small and secluded island in Seto Inland Sea, Hiroshima Prefecture, Japan. Now it is famous on social media as the “Rabbit Island,” a family-friendly resort with various tourist facilities populated by nearly five hundred fluffy creatures (The Asahi Shimbun, 2025). However, during World War II, the island was a production site for Japan’s chemical weapons program. It left behind a trail of poisonous legacy—buried chemical weapons—that still contaminate land and water and harm people’s health all across Japan and Northern China. Despite this, the existing memory discourse surrounding the island is relatively obscure, with certain official policies implemented to conceal the dangerous legacy from the public’s attention. Lack of awareness of Ōkunoshima not only undermines justice for the victims but also increases public vulnerability to ongoing threats.

The prioritization of a “positive” image for the island—one that drives tourism revenue while avoiding uncomfortable historical truths—means that its dark legacy remains obscured, leaving visitors and the wider public unaware of the dangers that persist.

One especially infamous case of Ōkunoshima’s legacy harming people’s health occurred some twenty years ago. In October 2001, Miyuki Aotsuka and her family moved into a new house in Kamisu City, Ibaraki Prefecture. Soon after, the Aotsuka family began experiencing health problems. Ryuji, the eldest son and the most severely affected, was diagnosed with cerebral palsy and left with lifelong disabilities. The cause of the problem was traced to the local well that supplied the entire community with tap water. In 2003, a government water quality survey found arsenic at a concentration 450 times higher than the national standard. The specific contaminant—diphenylarsinic acid—does not exist in nature. It had leaked from a buried concrete mass near the well, polluting the groundwater across the surrounding area. The Environmental Dispute Coordination Commission determined that the substance had likely been produced during World War II in a completely different part of the country—on the island of Ōkunoshima in Hiroshima Prefecture (Kamisu City Hall, 2019; Schumann, 2019; Tatsumi, 2022).

Although the total number of people affected by the incident remains unclear, 39 residents of Kamisu City filed a lawsuit against the national government and Ibaraki Prefecture, and 37 of them received compensations in 2012 (Pollution Adjustment Committee Secretariat, 2012; The Nikkei, 2012). Below, I will explain why weapons produced during a war that ended 80 years ago continue to pose a threat to people.

After World War I, Japan, like the United States and the Soviet Union, continued developing its chemical weapons (CW) program despite the growing global consensus to ban such weapons. Due to its secluded location, Ōkunoshima was chosen as the main production site for the program. From 1929 to 1945, the island housed CW production facilities, employing up to 6,000 people and producing hundreds of tons of poisonous substances. The CWs produced on Ōkunoshima included vomiting agents, tear gases, and the infamous mustard gas, which inflicted immense suffering on its victims. These weapons were used primarily in China during World War II, where they affected up to 80,000 people (Grunden, 2005; Mitchell, 2020).

In addition to Chinese soldiers and civilians, many Japanese workers on the island—some of whom were mobilized children and volunteer women—were also exposed to the toxic substances. Many later developed severe health issues, including chronic bronchitis, cancer, skin diseases, and pulmonary emphysema. For decades, the victims had to fight the government for compensation (Higuchi, 2015).

Shortly before Japan’s surrender in 1945, Japanese officials and military officers attempted to conceal evidence of the CW program. Poisonous substances produced on Ōkunoshima were buried or dumped into bodies of water across Japan and northern China, where many remain undiscovered to this day (Doglia, 2019; Embassy of the PRC, 2023)

However, this history remains largely unknown by the general public, as the island is primarily famous for its population of rabbits, which have become its main tourist attraction. This obscurity can be attributed to several factors. First, after Japan’s surrender, American military authorities sought to suppress information about the Japanese CW program for their own strategic purposes. As a result, despite ample evidence, not a single Japanese official was held accountable for the CW project at the International Military Tribunal for the Far East. This failure to criminalize the use and development of chemical weapons allowed for their near-unrestricted proliferation until the end of the Cold War, when the Chemical Weapons Convention was created (Guillemin, 2017).

The second factor was the Japanese government’s effort to obscure this “guilty page” of the country’s history from public memory. Although former employees of the island eventually secured compensation after decades of campaigning, Ōkunoshima never became a widely recognized memory site for Japan’s wartime atrocities. This was partly due to a tourism policy initiated by Takehara City in 1963, which aimed to “change the island’s negative image” by transforming it into a family resort. The policy received personal approval from then-Prime Minister Ikeda Hayato, himself a native of Takehara City (Doglia, 2019).

Now, Takehara City plays an ambiguous role in shaping the image of Ōkunoshima. On the one hand, the municipality supports the countermemory voices of local peace activists who run the Poison Gas Museum, which raises awareness of the island’s wartime legacy. On the other hand, the Takehara City Tourism Bureau largely continues the policy sanctioned by Ikeda Hayato more than 60 years ago. An analysis of official websites reveals that Ōkunoshima is primarily presented as a family-friendly resort where visitors can enjoy interacting with rabbits and experiencing the island’s “paradise-like” nature. The history of the chemical weapons program is mentioned only briefly, framed as a “dark history” that is disconnected from the present. This framing ignores ongoing issues, such as the contamination of land and water, even on the island itself, and distances the historical narrative from the actual victims—not only those who suffered during World War II but also those who continue to be affected decades later due to the buried chemical weapons scattered across Japan and China.

In 2014, Ōkunoshima gained widespread social media fame, attracting domestic and international attention. As a result, visitor numbers surged several times, surpassing 400,000 in 2017 (Tomikawa, 2023). The island’s image on social media was largely influenced by the “rabbit island” narrative promoted by official Japanese institutions. Studies indicate that visitors often perceive Ōkunoshima as “a natural petting zoo” or “a theme park” where entertainment takes precedence over historical awareness (Usui, 2022). According to data from Setonaikai National Park, 93% of tourists visit the island to interact with the rabbits, while only 30% mention war-related tourism (Ministry of the Environment, 2019). The director of the Ōkunoshima Poison Gas Museum, a local peace activist, offers an even lower estimate—only 10% of visitors come to learn about the island’s chemical weapons legacy.

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Although Ōkunoshima’s fame as “Rabbit Island” brings some indirect benefits to its historical memory—after all, more tourists visiting the island means more people have the chance to learn about its past—the existing tourism policy fragments visitors’ knowledge and distances the island’s problematic legacy from the present. With only a small group of local peace activists working to confront this issue and the topic absent from school education, the general Japanese public remains largely unaware of Ōkunoshima’s true legacy.

The founders of the Ōkunoshima Poison Gas Museum envisioned it as a true counterpart to the Hiroshima Peace Memorial Museum—a memory site that would highlight Japan’s wartime atrocities, absent from Hiroshima’s narrative, and serve as an entry point into the broader history of chemical weapons (Kristof, 1995). This way, it would connect Japan to other places that have suffered from chemical warfare, such as Yemen, Vietnam, and Syria, while serving as a warning about the ongoing dangers of buried chemical weapons, ensuring that tragedies like that of the Aotsuka family are not repeated.

However, the current tourism and education policies prevent Ōkunoshima from gaining recognition as a significant war memory site. The prioritization of a “positive” image for the island—one that drives tourism revenue while avoiding uncomfortable historical truths—means that its dark legacy remains obscured, leaving visitors and the wider public unaware of the dangers that persist.

References

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^{Suggested citation:
Dunichev, Dmitrii (2025, April 5). “Rabbit Island’s Buried Memory: How Tourism Policies Obscure Okunoshima’s Dangerous Legacy.” Trends in Peace and Sustainability 3(1): 1–3. <URL> Access date.}

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