I guess we owe an apology to Gareth Morgan, the New Zealand economist with the campaign to ban cats. We made fun of him a tiny bit for suggesting that you should get rid of your cat because it’s a ruthless killer of birds and an enormous threat to biodiversity. But it turns out that … well, your cat is a ruthless killer of birds and an enormous threat to biodiversity. Science says so. Sorry.

According to a paper in Nature Communications, cats are one of the major threats to U.S. wildlife, killing up to 3.7 billion birds and 20.7 billion mammals every year (far more than previous studies had realized). To be fair, it’s mostly feral cats doing the damage, but Fluffy is getting in on the action too, make no mistake. Domestic cats have been blamed for the extinction of 33 species worldwide — though feral cats kill three times as many critters, according to the new paper, which is a review of previously published research.

What can you do about it? Well, as Morgan said, euthanasia is “an option.” But come on, I know how you cat people are, with your toxoplasmosis parasites telling you that you need to take care of these fuzzy plants that hate you. (That is how toxoplasmosis works, so shut it.) You don’t care that they are tiny murderers! Maybe you rejoice in the idea that your furry overlords are such conquerors! But maybe just, like, try to keep them indoors if you can, because seriously this reign of terror is getting out of control.

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