Cats killing billions of animals in the US
Writing in Nature Communications, the scientists said stray and feral cats were the worst offenders.
However, they added that pet cats also played a role and that owners should do more to reduce their impact.
The authors concluded that more animals are dying at the claws of cats in the United States than in road accidents, collisions with buildings or poisonings.
The domestic cat's killer instinct has been well documented on many islands around the world.
Felines accompanying their human companions have gone on to prey on the local wildlife, and they have been blamed for the global extinction of 33 species.
But their impact on mainland areas has been harder to chart.
To find out more, researchers from the Smithsonian Conservation Biology Institute (SCBI) and the US Fish and Wildlife Service carried out a review of studies that had previously looked at the predatory prowess of cats.
Dr Pete Marra SCBIOur study suggests that they are the top threat to US wildlife”
Dr Pete Marra from the SCBI said: "Our study suggests that they are the top threat to US wildlife."
The team said that "un-owned" cats, which they classified as strays, feral cats and farm cats, were killing about three times as many animals as pet cats. However, they said pet cats were still killing significant numbers of animals, and that their owners should do more to limit the impact.
Dr Marra said: "We hope that the large amount of wildlife mortality indicated by our research convinces some cat owners to keep their cats indoors and that it alerts policymakers, wildlife managers and scientists to the large magnitude of wildlife mortality caused by cat predation."
A spokeswoman for the animal welfare charity the RSPCA said that a properly fitted collar and bell could reduce a cat's success when hunting by at least a third.