These days, it's hard to imagine a more adorable island than Rabbit Island in Japan. The island, also known as Okunoshima, is home to hundreds and hundreds fluffy wild rabbits, a haven that feels straight out of a cartoon.

Fluffy Bunnies Tainted by War

According to a report from The Guardian, there is a darker story behind this bunny-friendly isle though. During World War II, Okunoshima was used as a production site for the country's chemical weapons, producing more than 6,000 tons of poison gas in over a decade. The army kept the small isle a secret from the outside world, removing it from maps and keeping mum about its remote location.

Rabbits were brought to the island then, not to amuse tourists but to test the effects of the poison being produced.

While a number of people believe so, it's reportedly unlikely that the rabbits hopping around the island today are descendants of the ones that suffered from the weapons testing several decades ago.

"The rabbits are not descendants used in chemical weapons tested during the war," University of California San Diego professor Ellis Kraus told The Dodo. "The test rabbits were all euthanized by the Americans when they came to the island during the Occupation... about 200 of the poor things were being [used] in experiments by the Japanese."

One of the theories on how the new batch of rabbits came to occupy the island is schoolchildren brought eight of them here back in 1971. This group supposedly proceeded to breed and increase in number until now, when up to thousands reside in the small isle.

Boom of Tourism in Japan's Rabbit Island

Rabbit Island is now a popular tourist destination that has a golf course, camping grounds and stunning beaches. It's history remains part of the allure with tours of the old facilities and picturesque ruins scattered on the grounds.

Of course, a large part of the island's fame come from its cutest residents. Viral videos of dozens of rabbits hopping after tourists circulate the Internet and bring hordes of visitors to the island, who are encouraged to feed and play with the animals.

Tourism Harmful to Rabbits

There is some concern that the wave of tourists is actually harmful for the island and its fluffy inhabitants. Margo DeMello, program director for the Animals and Society Institute in Ann Arbor, Michigan, told Take Part that the rabbits suffer from a number of health issues and currently have a life expectancy of only two years. This is likely due to the lack of vegetation and inappropriate food provided by tourists.

"There are now about 1,000 rabbits on this two-mile island," DeMello said in mid-2016. "They've destroyed the ecosystem."

Read Also: Owl Café in Japan a Target of Animal Activists -- Here's Why