by Whit Gibbons

December 11, 2005

Outdoor cats are amazing killers. Feral and domestic cats that are allowed to roam outside kill more than 20 million birds each year in Britain. In one published account, an ecologist estimated that in a single state, Virginia, cats kill at least 3 million songbirds and 27 million native mammals annually. A study documented that the greatest nonhuman cause of mortality to some Australian wildlife was feral cats.

The statements above are facts. The essence of their truth is inarguable. But whether cats should always stay inside or be permitted outdoors on a regular basis is a slightly more volatile subject than politics, religion, or the use of cell phones in restaurants. People tend to take inflexible positions about the proper place for cat whereabouts (or, indeed, whether domestic cats have any merit at all). Conversations among casual acquaintances, or even close friends, tend to go more smoothly without
individual positions about cats being identified. But if you ever do want to challenge your best friend about why she lets her cats out to pillage wildlife in their heartless way or why he keeps his cats imprisoned in a stuffy apartment to serve a life sentence of boredom, you should first look
at both sides of the story.

The inside-cat position is that outdoor cats take more than their share of native wildlife. Some ecologists consider cats to be the most dangerous carnivore in many regions because of their large numbers, stealth, and agility. Plus, unlike native predators, they get all they need for sustenance when they go inside. But an inclination to kill, whether hungry or not, makes cats a potential menace to all small wildlife around the yard. Scientific documentation of the impact of domestic cats on native wildlife is convincing.

But can a person be a proponent of native wildlife and also have cats that live outside? Someone who once wrote me about the inside-outside cat issue said, "Cars kill far more native wildlife than my cats. One, named Kat, kills a few mice, bunnies, and lizards a year??how many of the same are killed by automobiles? I can assure you more population damage is done by people in cars than by Kat. My other cat, Spencer, is not even part of the equation. The only `kill' he has ever brought home was a dried?up lizard that had been run over by a car days earlier. Of course, I did turn on the deck light once to find Spencer and a possum eating out of the same food bowl. Spencer looked a little confused but kept eating. So did the possum. But I bet that possum will kill a lot more wildlife over the year than Spencer and Kat put together. So why shouldn't my cats go outside?"

Another individual said, "I am puzzled by the concern some people have for native wildlife that suffers because house cats go outside. What exactly is the problem? No animal has gone extinct because of cats. In fact, I have never heard of any species of wild animal even being eliminated from a region because of `killer' cats. Lizards, chipmunks, and small birds still seem to be around my house, along with my outdoor cat. What is the problem people have with outdoor cats?"

Outside-cat lovers often ask whether house cats that kill small animals have a greater environmental impact than native predators would have if they were still around in abundance. Didn’t native prey species have to deal with bobcats, foxes, and coyotes before cats were on the scene? As someone
noted, “Maybe house cats are simply filling a role that we have eliminated by our removal of natural predators. Maybe they are actually returning the outdoors closer to a natural system than what we have now with the loss of our native predators."

Inside cats or outside cats. Which should it be? If you want to stay on speaking terms with your friends and acquaintances, you can loudly profess your die-hard political convictions, proselytize for your religion, and interrupt lunch for a conversation on your cell phone. But you should probably keep your opinions about their cats to yourself.

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