Are the Feral Felines on Cat Island Fixed? The Truth About Japan’s Famous Cat Haven


Cat Island is located off the southern coast of Japan in the Ehime prefecture. It is a small island covering only 11 acres and is officially named Tashirojima. The island has become famous for its large population of stray cats that originated from pets left behind when inhabitants evacuated the island. At its peak there were over 100 cats roaming the island, giving rise to its nickname as Cat Island. The cats are fed and cared for by the island’s human inhabitants and have become a popular tourist attraction. While many find the cats endearing, the large feral cat colony has raised concerns over its impact on the local ecosystem and efforts to control the population.

History of Cats on Cat Island

Tashirojima, also known as Cat Island, is a small island off the coast of Ishinomaki City in Miyagi Prefecture, Japan. The island became known for its large stray cat population beginning in the 1940s.

Cats were first introduced to Tashirojima in the 17th century when the island was used as a silkworm farm. The cats were brought to the island to help control the rat population and protect the silkworms. During World War II, the island was forced to evacuate in 1944 due to air raids on nearby Ishinomaki. When residents returned in 1949, they realized the cats they had left behind had survived and reproduced significantly in their absence. The cats had become the islands main inhabitants and predators in the ecosystem.

The fishermen who returned to the island after the war began to regard the cats as good luck charms. According to local legends, a cat had once rescued a drowning fisherman who had fallen from his boat near the island. The fishermen built a small cat shrine on the island as a place of worship and to show their appreciation for the cats. The cat population continued to grow unchecked in subsequent decades, reaching over 100 by the 1980s.


Current Cat Population

The current cat population on Cat Island is estimated to be around 100-120 cats according to various sources. The island is only about 1 mile in circumference, so the cat density is quite high at over 100 cats per square mile. The cats are mostly strays and ferals that roam freely around the island. They can be found lounging on the beaches, strolling down the walking paths, and mingling near the few houses on the island. The cats are known to be generally friendly and used to interacting with the small human population as well as tourists who visit the island. According to the Rover blog, the cats on Cat Island are well-cared for and even have scheduled feeding times courtesy of the local fishermen.

Impact on Local Wildlife

Feral and free-ranging cats pose a significant threat to local wildlife populations on islands around the world. Studies have shown that cats have contributed to multiple extinctions of birds, reptiles and mammals on islands (Medina et al. 2011). Birds are especially vulnerable, with ground nesting and flightless bird species being among the most heavily impacted (Loss et al. 2013).

On islands with high densities of feral cats, predation by cats is one of the leading causes of bird mortality. Cats are estimated to kill up to 3.7 billion birds per year in the continental U.S. alone (Loss et al. 2013). The impacts are even more severe on isolated island environments like Cat Island. Studies have found that feral cats are responsible for at least 14% of global bird, mammal, and reptile extinctions and the extinction of over 60 species of birds, mammals, and reptiles (Medina et al. 2011).

TNR Efforts

The Islands Feral Cat Project is a non-profit organization that has been working to control the feral cat population on Cat Island through a Trap-Neuter-Return (TNR) program. TNR involves humanely trapping feral cats, spaying or neutering them, and then returning them to their colony (Islands Feral Cat Project). According to the Islands Feral Cat Project website, they have successfully trapped and sterilized over 600 feral cats on Cat Island since starting their TNR efforts.

The town government of Ehime has also implemented an extensive TNR program on Cat Island in recent years. They aim to have over 80% of the island’s feral cat population sterilized in order to control breeding and stabilize the population. As of early 2018, it was reported they had sterilized 944 cats, which was about 64% of the estimated population at that time (Japan Today).

Challenges of TNR

Carrying out effective TNR programs on islands with large feral cat populations like Cat Island poses significant challenges. The most notable difficulty is trapping and fixing a sufficiently large number of cats to curb population growth. According to a report on Japan’s cat islands, “TNR programs require the trapping and neutering of at least 75% of the feral cat population in an area in order to be successful at reducing the population over time” ( Given Cat Island’s estimated population of 100-120 cats, TNR efforts would need to successfully trap and neuter at least 90-100 cats to impact population levels. However, trapping feral cats that have learned to avoid human contact can be extremely difficult.

Alternative Population Control Methods

While Trap-Neuter-Return (TNR) programs have proven effective for controlling feral cat populations in many areas, some communities explore alternative options. According to the article Ineffective Methods of Controlling Cat Populations, other population control methods include:

  • Trap and remove programs, where cats are taken to shelters or rescues for adoption.
  • Extermination methods such as shooting, poisoning, or other non-shelter euthanasia.

A key downside to trap and removal programs is that feral adult cats do not adapt well to living indoors. Shelter space is better utilized for adoptable cats and kittens. Extermination methods are widely considered inhumane and unethical. They also tend to be ineffective, as removing some cats creates a vacuum effect where new unneutered cats move into the vacated territory and breed.

Ultimately, TNR remains the most humane, effective long-term method for stabilizing and reducing feral cat colonies. It stops reproduction and allows adult cats to live out their lives in their familiar environment. Combined with public education and adoption programs for kittens, TNR can humanely address community cat overpopulation.

Adoption of Cat Island Cats

The primary organization focused on adoption of cats from Cat Island is Island Cat Resources and Adoption (ICRA), a nonprofit based in Alameda, California. ICRA has made substantial efforts to facilitate adoption of cats from Cat Island to help control the population. According to their adoption page, ICRA currently has dozens of cats and kittens available for adoption that were originally found on Cat Island.

ICRA frequently posts photos of adoptable Cat Island cats on their Facebook page to raise awareness. They transport cats from Cat Island to their facility in Alameda where they are spayed/neutered, vaccinated, treated for any medical issues, and cared for until adopted. The adoption process includes an application, home visit, and adoption fee starting at $125 to cover a portion of care expenses.

According to ICRA’s estimates, they have facilitated the adoption of over 500 cats from Cat Island to date. However, they note more support and adopters are still needed to make a substantial impact on controlling the population humanely. ICRA provides comprehensive support to adopters and continues efforts to increase Cat Island cat adoptions. Their dedication is making adoption a viable way of improving lives for the cats of Cat Island.

Future Outlook

The long-term expectations for the cat population and TNR efforts on Cat Island are uncertain. While TNR programs have shown success in reducing cat populations in some areas, TNR alone may not be enough to control the large cat population on Cat Island. As of 2021, there were an estimated 120 cats living on the island, outnumbering the human population of 100.[1] With limited space and resources available, the large cat population poses risks to native wildlife populations and the overall ecosystem health of the small island.

Some experts believe that the cat population has reached its carrying capacity and will stabilize through natural population dynamics.[2] However, continued immigration of stray and abandoned cats from the mainland could hamper population control efforts. More intensive management strategies, combining TNR with adoptions, may be needed to humanely reduce the cat population to more sustainable levels. Continued monitoring, data collection, and adaptive management will be key to finding an optimal long-term solution. Overall, the outlook for Cat Island remains uncertain, but focused human intervention and community support offer hope for protecting both the cat and wildlife populations that call the island home.

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In summary, the cat population on Cat Island has grown significantly over the years, placing pressure on local wildlife. Volunteers and organizations have worked to implement TNR programs to help control the cat population, but challenges remain. While adoption of socialized cats is possible, the future outlook depends on continued TNR efforts and public education on responsible cat ownership. More needs to be done to humanely manage the cat population while protecting the island’s vulnerable endemic species. Overall, the large cat population on Cat Island remains an ongoing concern, requiring creative long-term solutions rooted in compassion for animals and the environment.

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