In a 2011 paper published in the Journal of Wildlife Management, Jeff Horn and his co-authors estimate the home range of owned and unowned cats, arguing that “greater activity levels and ranging behavior suggest unowned cats have a greater potential impact on wildlife than do owned cats.”
“Our results indicate that feeding and owner care modifies the space use and activity of free-roaming cats, information that is important for making decisions on controlling cat populations and the potential spread of disease.” 
Although the authors don’t specify which method(s) of control they consider preferable, it’s safe to assume TNR is probably off the table. Consider, for example, Horn’s description of cats as “invasive” and his recommendation that “management steps need to be taken in regards to this species, despite the social and political controversies that surround it.”  For Horn and his co-authors (and many of their colleagues in the conservation community), the “management” category seems to include almost exclusively lethal methods.
Of course, anybody proposing the killing of this country’s most common companion animal on an unprecedented scale,* ought to provide some solid evidence—and, while we’re at it, at least one feasible funding mechanism—to advance the necessary public policies. But a review of Horn’s data reveals a number of problems, raising serious questions about the validity of his conclusions and justification for his recommendations. Read more