It’s difficult to imagine now—after a banner week of revelations, accusation, and obfuscations—but headlines earlier this month were dominated by dire warnings of a different kind: a looming ecological collapse as demonstrated by dramatic declines in North America’s birds. Coverage included stories in the New York Times, Washington Post, The Atlantic, National Geographic, Vox, Scientific American, and many other publications.
According to the reports, North American bird populations have declined by about 29 percent since 1970, a loss of roughly 3 billion birds.
Which leaves only about 7 billion birds. But just six years ago, researchers (some of which were also involved in this most recent study) published a paper estimating that outdoor cats kill 1.3–4.0 billion birds annually in the contiguous U.S. alone.
Are we really expected to believe that this one source of mortality (estimated only for the Lower 48 states, remember) is responsible for killing more than half of the continent’s bird population, year in and year out? Although numerous news accounts have referred to cats as contributors to the declines in bird abundance, I’ve yet to see one questioning this basic arithmetic (see Footnote 1).