An Island Overrun with Rabbits
Ōkunoshima, a small island in Japan’s Seto Inland Sea, is home to hundreds of feral rabbits. Tourists flock to the island, now called Usagi Jima, or “Rabbit Island,” to feed and photograph the tame bunnies. With no natural predators and an abundance of food from visitors, the rabbit population thrives.
A Hidden History of Chemical Weapons
Before becoming a rabbit haven, Ōkunoshima was a top-secret site for poison gas production during World War II. The Japanese Imperial Army manufactured mustard gas and phosgene there, using the chemicals in warfare. The island was so classified that it was removed from official maps. Some believe that rabbits were originally brought to the island for gas testing.
The Mystery of the Rabbits’ Origins
Historical records suggest that test rabbits were euthanized after the war, making their connection to today’s rabbits unlikely. Another theory suggests that in 1971, a group of schoolchildren released eight rabbits, which multiplied rapidly due to the lack of predators. Today, the population is estimated to be around 1,000.
Tourism’s Unintended Consequences
While tourists enjoy feeding the rabbits, researchers warn that irregular feeding patterns and poor diets have harmed the animals’ health. Many live only two years, far below their natural lifespan. The island’s ecosystem has also suffered, with rabbits overgrazing the land, leaving little vegetation for them to survive on during off-peak tourist days.
Ōkunoshima, a small island off Japan’s coast, is home to tame rabbits. Tourists feed and photograph them, but few know its past. Once erased from maps, it was a poison gas factory in World War II. How did it go from a wartime site to a rabbit paradise?🧵👇 pic.twitter.com/vpsT9HqVt2
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