How Cats Affect The Environment

Domestic cats do not just affect specific animals, but also whole populations of species

By: Rory Bierhanzl, Jounalist

March 6, 2025

The environment is fragile as it is, and now as we progress into a new era of technology, new information about how we continue to affect the environment becomes a bigger and bigger issue we face. Authors Scott R Loss and Peter P Marra wrote in a 2017 study, “The domestic cat is among the most ubiquitous and environmentally damaging invasive predators on Earth.” Domestic cats, though shown from studies by an author on Poe.com, “According to recent surveys, approximately 63% of Americans say they like cats. The current US population is estimated at 331 million people, which amounts to around 208 million Americans who like cats.” Cats are a common pet that is loved and adored worldwide, but they are not nearly as good for the environment as you might think. As the American Bird Conservancy states, “Outdoor domestic cats are a recognized threat to global biodiversity. Cats have contributed to the extinction of 63 species of birds, mammals, and reptiles in the wild…” The National Institute of Health has discovered that almost 20% of domesticated cats in America are outdoor cats. Not only have domesticated and feral felines become so common in today’s society, but the now high level of felines in the area is starting to show serious environmental side effects. The American Bird Conservancy has estimated that roughly 2.4 billion birds are killed by outdoor cats each year, with a little more than half coming from feral street cats. To compare, the amount of birds killed by flying into windows is predicted to be around 599 million, and 200 million from automobiles. And that is just birds. Both feral and owned cats can hunt everything from small mammals to reptiles and frogs. Cats have killed 6.30 to 22.30 billion mammals annually, mostly by owned, free-ranging felines. Cats, domesticated and feral, have one of the biggest impacts on the environment then other human caused issues, and if we don’t learn new strategies to keep our cats away from important ecosystems and species, we may have to resort to stop our cats from leaving our homes.