The wild cats on Tsushima Island off Nagasaki Prefecture are facing extinction, as only 80 to 110 of them are believed still existing in the wild.
Zoo experts and local environmentalists are trying to breed Tsushima leopard cats in zoos and other facilities but are finding it difficult because the animals are stressed and won't become tame.
"They don't adjust to being around humans," said Eiji Nagao of Fukuoka's City Zoological Garden. "The cats won't approach us, and we can't even touch them."
The cats are on the government's Red List of animals on the verge of extinction and are also designated as a protected species.
The cats' population has rapidly decreased because of human encroachment on their wooded habitat.
The zoo, which started the breeding effort around 10 years ago, currently has 10 Tsushima leopard cats. Another 22 are in facilities in Tokyo, Yokohama and Toyama Prefecture.
Zoo officials are now considering releasing cats raised in captivity into the wild, but the number must reach 100 before this can be done, an official at the Tsushima Wildlife Conservation Center on the island said.
Learn more about big cats and Big Cat Rescue at http://www.bigcatrescue.org