Pet kitties and their wild feral relatives kill a shocking 500 million birds and over 3 billion other animals according to new studies, prompting a leading Washington-based bird protection group to demand that local governments order their dog catchers to snag cats too.

One disturbing new study is based on evidence from "KittyCams" strapped on to 60 outdoor pet cats in Athens, Ga. The results: They each averaged 2.1 "kills" a week. Just 13 percent were birds, the rest voles, lizards, chipmunks, frogs and small snakes.

Based on the joint University of Georgia-National Geographic study of pet cats and another of feral cats from the University of Nebraska, the American Bird Conservancy said over 4 billion birds and animals are killed yearly by the felines, four-times the previous estimate. The group blames the extinction of some birds on the killer cats. "Cat predation is one of the reasons why one in three American bird species are in decline," said George Fenwick of the conservancy.

While it would be hard to get cat owners to keep their pets inside, the group wants cat lovers and local governments to stop coddling feral cats and round them up.

"Wildlife are being slaughtered and so often community leaders only seem to express concern for the cats," conservancy spokesman Robert Johns told Secrets.

"Feeding and protecting feral cats is not a win-win. It's a win for the cats, a death sentence for local wildlife, and potentially serious health risks for people in the community," said Johns. "We don't have feral dogs running loose and being managed in colonies. We shouldn't be doing it for cats. Local governments need to get the blinders off, start seeing this as a serious problem and start dealing with it. Estimates suggest that there are hundreds of thousands of feral cats in the D.C. area alone - not a few here and there. There are about 90 million nationwide."

The study of pet cats was conducted by the University of Georgia and the National Geographic Society's "CritterCam" program. Among the other highlights: Pet cats bring less than one of four kills home to show-off to their owners. A previous study of feral cats was conducted by the University of Nebraska and linked the extinction of 33 birds to the wild kitties.