Sara J. Ash, a professor of ecology and conservation biology at the University of the Cumberlands in Williamsburg, Ky., said that the results highlighted the deep divide between cat owners, who see their individual animals as doing what comes naturally, and ecologists, who view cats as a predatory, nonnative species.

“These owners think, ‘My cat only kills two mice a day,’ ” Dr. Ash said. “But they don’t think about the high density of well-fed cats throughout their neighborhood.”

The study’s cat owners were generally able to predict whether their pets would bring home prey, but they fared poorly at estimating how much. Among 43 cats tabulated in the Cornwall village of Mawnan Smith, the average monthly catch ranged from none to 10. Over four months, the cats delivered a total of 325 animals: Nearly 60 percent were rodents, and 27 percent were birds. (According to researchers, 6.2 percent were unidentifiable.)

Although Mawnan Smith and another village in the study, Thornhill, in Scotland, are in rural settings, these owners’ reactions corresponded with those of urban cat owners in Britain. In a 2012 study, they said overwhelmingly that they did not believe cats depleted certain bird populations.

John Bradshaw, a professor of anthrozoology at the University of Bristol in England, pointed out that the owners in this latest study counted only the prey their cats had brought home, and did not know how many creatures the cats might have left elsewhere — scenarios vividly illustrated in a 2013 University of Georgia study by researchers who attached “kitty cams” to 55 pet cats. Those cats left behind nearly half the prey they had killed.

But Dr. Bradshaw, the author of “Cat Sense,” questioned whether cats were really having an ecological impact.