Outdoor cats are bad for birds, lizards and small mammals. Roaming outdoors is not great for the cats, either.

Illustration by Ginette Lapalme

ONCE upon a time I had a cat named Lucky, and the name fit. She turned up on our doorstep as a stray and stayed with us for 10 years, until her rather gruesome demise. (More about that later.) I liked her because she was a free spirit, and a survivor, going out for two, three, even five days, in all seasons. She’d show up when it suited her, waiting in the dark before dawn till I came downstairs and turned on my desk lamp. Then she’d make her presence known by rising up on her hind legs and gently scratching with her forepaws on my window.

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Like a lot of other cat owners, I used to think that when Lucky went outside and, now and then, killed an animal, she was “just doing what’s natural” for a cat. I was aware that cats have caused or contributed to the extinction of 33 species. But all of those species were living on islands and many had likely never seen a predator before early navigators introduced cats. The mainland nature around me was savvier than that, I figured, and had the scale to handle incidental killings by a few house cats.

But that is no longer true, if it ever was. …

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Using deliberately conservative assumptions, federal researchers recently estimated that free-ranging cats killed about 2.4 billion birds annually in the Lower 48 states, a substantial bite out of the total bird population. Outdoor cats also kill about 12.3 billion small mammals a year — not just the proverbial rats and mice but also chipmunks, rabbits and squirrels — and about 650 million reptiles and amphibians. In some cases, they are pushing endangered species toward extinction.

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Read the whole article here: The Evil of the Outdoor Cat