WASHINGTON (WUSA) -- Sorry to tell you this, but Fluffy is a killer and on a scale that's hard to imagine.
A new report just out from the Smithsonian and the US Fish and Wildlife Service finds outdoor cats are killing billions of animals a year.
The study in the scientific journal Nature Communications says cats kill more wildlife than cars, pesticides, windows or windmills.
Steve Holmer of the American Bird Conservancy says the numbers shocked him because they are two to four times earlier estimates.
The numbers are staggering. America's outdoor cats kill an estimated 2.4 billion birds, and 12.3 billion small mammals every year and we're not talking rats. We're talking chipmunks, rabbits and squirrels.
Feral cats account for most of the bloodshed. But some of it is also from cats allowed by their owners to roam outside.
The study was peer-reviewed, and looked at 90 earlier surveys including some involving small cameras attached to cats on the prowl.
But Alison Grasheim of the Bethesda advocacy group Alley Cat Allies says euthanizing wild cats is not a solution. She maintains the study is re-wrapped old data, and says habitat destruction is a much greater cause of falling populations of wildlife.
The American Bird Conservancy estimates there are 300 colonies of feral cats in DC alone and warns cats could leave us with a silent spring a spring without the beautiful song of migrating songbirds.
The study says un-owned cats account for almost 90 percent of the wildlife kills. But the Washington Humane Society, and many other groups, say it's better for your cat and for the wildlife to keep it indoors.