Killer Kitties

Don't be fooled by their elegant gait and trusting meows. These cuties by day are brutal predators by night.

Humans first domesticated cats in the Fertile Crescent in the Middle East and later in ancient Egypt, where their presence somehow morphed into the cat-faced goddess Bastet. Cats’ careful balance between being cuddly, independent, and dangerous made them a hit wherever they ventured.

From companionship and whatever purring is, to trouble with mice in the granary or rats in the hold of your ship. Cats are fun to hang out with, and their quick reflexes and killer instinct helped them spread across the world like wildfire. They will pounce on anything small with a pulse, and clean up after themselves as if nothing happened.

And while they rarely come up in conversation as a fearsome invasive species—many animal lovers are cat lovers—they should. Cats' ubiquity has made us accept their dark side without blinking.

Not only are cats stealthy killers, but their sheer numbers steadily stack the odds against any unsuspecting songbird or field mouse. Europe hosts at least 127 million domestic cats, not including feral cats. In the US, people own roughly 100 million of them. As a wild animal, you can never be too sure a hungry kitten isn't right around the corner.

While domestic cats contribute to the problem, feral cats—who live off the spoils of their hunt—are responsible for the lion's share of wildlife kills. Together, domestic and feral cats go after 2000 wildlife species worldwide, of which hundreds of preservation concern.