by Dylan Reynolds
November 07, 2019
We often think of outdoor cats as lovable wanderers, napping in puddles of sunlight and patrolling neighborhoods for pests to affectionately deliver them to your front door. However, outdoor cats can present a very real threat to our ecosystem.
A 2013 study found that free-ranging domestic cats kill between 1.3 and 4 billion birds in the United States each year, making them the leading human-caused threat to birds in the country. The study also found that outdoor cats kill anywhere between 6.3 and 22.3 billion mammals and reptiles annually.
Approximately one-in-three of these deaths were brought about by cats with owners who regularly allowed them to venture outside, while the remainder were primarily caused by feral cats––those who were born and raised in the wild, often with little to no human contact.
In the United States, around 90 million cats have assigned owners, while between 30 and 80 million are believed to be stray or feral. Among cats with owners, around 70 percent are indoor only cats and about 25 percent move freely between inside or outside. The remaining five percent are outdoor only cats.
In some cases, predation by cats has been devastating. A 2011 study found that feral cats are responsible for at least 14 percent of all bird, mammal and reptile extinctions worldwide, and are a leading threat to almost eight percent of endangered species. Feral cats prove especially problematic on small islands, which tend to house large amounts of biodiversity. When confined on an island, cats begin to reproduce rapidly, eventually overwhelming the island’s fragile ecosystem.
Outdoor cats also present a problem right here in the Chesapeake Bay watershed. Some of the Bay’s most beloved birds face predation from domestic cats, including the eastern bluebird, Baltimore oriole and ruby-throated hummingbird. These birds are often drawn to suburban gardens, bird feeders and bird houses, where they make perfect prey for any cats who might be lurking nearby.
There is no perfect solution to the problem of outdoor cats. They are instinctive hunters and are always eager to make a feathered friend. However, there are some steps you can take to help decrease their impact on the Bay watershed:
- Keep your cat indoors: Keeping your cat inside can do more than protect the ecosystem. There is evidence that indoor cats live longer, healthier lives than cats living outdoors, where they are more prone to predation, disease and accident. In fact, indoor cats are estimated to live as much as four to six times longer than outdoor cats.
- Tag your cat: One of the best ways to prevent the spread of outdoor cats is to make sure your own cat never wanders too far. Tagging your cat with a microchip or an identification tag can go a long way to making sure your cat always finds its way home.
- Avoid feeding feral cats: While it might feel like a harmless gesture, feeding a feral cat will only encourage its colony to continue breeding. These cats can spread diseases and are often unfriendly towards humans. Therefore, it’s best to keep your distance.
- Install bird houses responsibly: Bird houses can be a wonderful addition to your backyard, providing a valuable home to the watershed’s native birds. However, it’s important to keep your bird house elevated and out of reach of any feasting felines.
Cats make amazing pets, but even the most well-meaning of kitties can get up to mischief when left to the great outdoors.