Tashirojima is a small island in Ishinomaki, Miyagi Prefecture, Japan. It lies in the Pacific Ocean off the Oshika Peninsula, to the west of Ajishima. It is an inhabited island, although the population is quite small (around 80 people as of 2015, compared to around 1,000 people in the 1950s).
It has become known as "Cat Island" owing to its large stray cat population that thrives as a result of the local belief that feeding cats will bring wealth and good fortune. The cat population is now larger than the human population on the island. There are no pet dogs on the island due to the large cat population.
In Japan's late Edo Period, much of the island raised silk-worms for their textiles. The residents kept cats to chase the mice away from their precious silk-worms. In 1602, all pet cats in Japan were freed by decree to counter the rampant rodent population that threatened the silk-worm industry. The release of Tashirojima's pet cats is what created the island's thriving wild population.
The island is also known as Manga Island, as mangaka Shotaro Ishinomori planned to move to the island shortly before his death. There are manga-themed lodges on the island, resembling cats.
According to wikipedia.org