When we think of invasive species, many will think of bugs or ocean creatures hitching rides in ballast tanks. But being an invasive species is not just about being unsightly or even mistakenly introduced to the environment. The hallmark of invasive species is that they begin to inhabit environments that they were not introduced to through natural means and have a negative effect on their environment. Cats are categorized as invasive species by many organizations, especially feral or unsocialized cats that live outside. Originally native to Northern Africa and Mesopotamia, the creatures have been domesticated for over ten thousand years.
However, the cat population has spiraled out of control. According to the American Bird Conservatory, 100 million feral cats currently reside in the United States. Feral cats are outdoor cats that have limited contact with humans and are known for being shy and difficult to acclimate to a life of being a pet. Cats can be socialized before they turn four months old, but it becomes a harder process with a higher chance of failing after that. Despite being feral, cats are not wild creatures. Few can subsist fully on hunting, and most are fed by humans either directly or by consumable waste that people throw away.
Cats hunting is the main issue, as they kill native populations of small animals and birds, including endangered species. This is a major problem in areas such as Hawai’i and Australia, which hold many endangered species. Hawai’i hosts many colorful birds that aren’t found in other regions of the world, while Australia’s endangered small marsupials and rodents are easy prey for an outdoor cat. Cats were kept by humans to hunt rodents that threatened their food supply, and hunting is integral in the nature of a cat. Discouraging this behavior is not doable. These feral cats are not able to be kept as pets, and no one wants to be responsible for creatures the same species as their beloved house pets. So what can be done?
Trap-neuter-release, or TNR, is the most common process currently used to keep the number of feral cats under control, especially in the United States. Volunteer groups go out and set traps for feral cats, who are then brought in to be neutered or spayed before being released back into the wild. This allows them to live their lives the way they are used to, but prevents them from further adding to the numbers of feral cats. Female cats can get pregnant as young as four months old and have up to four litters per year, but male cats are even tougher hunters to endangered species and can father up to a thousand kittens! Catching male cats and sterilizing them is therefore a high priority for these volunteers.
Feral cats are not the only cats that are putting the environment at risk, however. Environmentalists have been warning people about the dangers of any outdoor cat for years. Cats will hunt and kill birds and rodents that are important to the environment. As they are not part of the native ecosystem, this can be disastrous. Cats also spread toxoplasmosis, which over 40 million people in America carry. This parasite is the leading cause of death by foodborne illness and is found in cat feces. Furthermore, keeping a cat outdoors poses risks to the cats themselves. Outdoor cats are exposed to cars, other wild animals, and harsh weather conditions. Overall, keeping cats indoors and getting them spayed or neutered remains important for the health of both cats and the environment.
