Tashirojima (Japanese: 田代島) is a small island in Ishinomaki, Miyagi Prefecture, Japan. It lies in the Pacific Ocean off the Oshika Peninsula, to the north of Aji Island. The population was around 80 people in 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 population of the cats.

The island is divided into two villages/ports, Oodomari and Nitoda. The neighboring Aji Island used to belong to the town of Oshika, while Tashirojima was a part of the city of Ishinomaki. In April 2005, Oshika merged with Ishinomaki, so now both islands are a part of Ishinomaki.

Since 83% of the population is classified as elderly, the island's villages have been designated as a "terminal village" (限界集落, genkai-shūraku) which means that with 50% or more of the population being over 65 years of age, the survival of the village is threatened. The majority of the people who live on the island are involved either in fishing or hospitality.

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.

History: In Japan's late Edo period, much of the island raised silkworms for their textiles. The residents kept cats to chase the mice away from their precious silkworms. In 1602, all pet cats in Japan were freed by decree to counter the rampant rodent population that threatened the silkworm industry. The release of Tashirojima's pet cats is what created the island's thriving wild population.

In 1989, Tashiro Elementary School closed down and was turned into an educational center. In 2008, the educational center closed. In 2000, Manga Island, a tourist

facility, was built. In 2007, a 6 km (4 mi) and 10 km (6 mi) race called Hyokkori Hyōtan Tashirojima Marathon was held.

In 2011, the island was hit by the Tōhoku tsunami, which destroyed the harbor and caused the ground to subside, leaving the villages more exposed to both flooding during high tides and strong coastal winds. The local cat population fled inland to escape the tsunami, and only a portion returned to the villages in the aftermath. The tsunami also caused an outbreak of parva in the region, and at least 80 cats on Tashirojima were captured and vaccinated in a matter of days to forestall the disease. Due to the loss of the harbor, which was used primarily by a ferry service and Tashirojima's small fishing industry, a number of fishers and their families moved away.

By 2015, government workers had rebuilt much of the harbor to raise the coastline and stop the floods, but the island's fishing industry remained diminished. However, tourism was steady, and at least two regular visitors to the island had taken up residence there.

Feline Population: By 2015, the human population numbered around 80, while the total cat population exceeded that by several hundred, with at least 150 cats permanently residing in one of the villages. A vet traveled to the island every two months to examine the village-dwelling cats. While the cat population is mostly made up of crossbreeds and mixed-breed cats, one distinct breed commonly seen on the island is the Japanese Bobtail.

In Japanese culture, cats are considered to bring good luck, said to bring money and good fortune to all who cross their path. Some even claim that it was the cats who kept the majority of the island from being destroyed during the Tohoku earthquake and tsunami in 2011.