by Whit Gibbons

January 23, 2005

Someone recently asked if we were going to let our two kittens, Jack and Rita, be outside cats. My first response was that "letting them outside" was too moderate a term, noting that the next time Jack shredded the living room curtain into strips of spaghetti he would not have to be "let" outside, he would already have been thrown out. Probably at least into the neighbor's yard. Of course, the real question was whether having outside cats was the proper thing to do environmentally.

Numerous scientific articles have documented that domestic cats have a serious environmental impact on native wildlife. Outdoor cats kill staggering numbers of songbirds, lizards, and small mammals every year. Some environmentalists would go so far as to place bans on letting cats roam free in a neighborhood. Others take the position that a person can be a proponent of native wildlife and also have cats that live outside.

The issue is not like a jellicle cat, black and white, but instead has many levels of gray. Anti-outdoor-cat advocates take firm positions that domestic cats turned out for even part of the day cause great environmental harm by relentlessly killing small wild animals. Nonetheless, providing justification for letting typical house cats have free rein out-of-doors is not that difficult. The following are some of the comments I have received in support of letting cats have their way outside (as they are accustomed to doing inside).

One individual commented, "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 ever 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 still seem to be around my house, along with chipmunks and small birds. I ask again, what is the problem people have with outdoor cats?"

Another person wrote, "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 cars (thus, by people) than by Kat. Also, does the fact that cats are not native exclude them from being a part of the legitimate food chain?

“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. I did turn on the deck light recently 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?"

And here’s an interesting environmental perspective: "House cats that go outdoors and kill small animals need to be viewed from the position of whether the environmental impact they are having is any greater than native predators would extract if they were around. Would not all these small animals have to deal with bobcats and coyotes and foxes in the real world of native animals? Maybe house cats are simply filling a role that we have already eliminated by our removal of natural predators. Maybe house cats are actually returning the outdoors closer to a natural system than what we have now without native predators."

Whether people should be required or at least encouraged to keep their cats indoors will never be resolved to everyone's satisfaction. As far as Jack and Rita go, they will probably stay inside, in part because we enjoy watching the birds in the backyard. And to be sure, the cats would take their toll. But also, as accurately noted above, cars kill far more animals than do outdoor cats. I am less worried about our backyard wildlife than about finding either of our kitty cats dead in the street that runs in front of the house.

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