Nature Communications is a journal dedicated to publishing research in the sciences. They recently published a controversial report on the findings of a Smithsonian Conservation Biology Institute study. The results quickly became fodder for an uncritical media willing to accept its dubious findings.
Curiously, the authors elected to place their “results” in the mainstream media rather than submit them for peer review – suggesting the report was never meant for scientists, but to misinform policy makers.
The study estimated that domestic cats in the United States kill a median of 2.4 billion birds and 12.3 billion native mammals, like shrews, chipmunks and voles, a year.
This estimate is two to four times higher than mortality figures previously bandied about, making the domestic cat the single greatest human-linked threat to wildlife in the nation – greater than automobiles, pesticides and poisons, collisions with skyscrapers and other so-called anthropogenic causes.
The report comes with many uncertainties and seems purposely designed to fuel the sometimes vitriolic debate between environmentalists who see free-roaming domestic cats as an invasive species and animal welfare advocates who are concerned with the millions of cats (and dogs) euthanized in animal shelters each year.
Both sides do agree on two points; pet cats should not be allowed to prowl the neighborhood at will, any more than a dog or a horse; and cat owners who insist that their felines “deserve” a bit of freedom are both irresponsible and not very cat friendly.
Projects like Kitty Cams at the University of Georgia attached cameras to the collars of indoor-outdoor pet cats to track their activities. Cats were not only filmed preying on cardinals, frogs and field mice but were also seen lapping up antifreeze and sewer sludge, dodging moving cars and sparring violently with large dogs.
This is why the I say if you love your cat, keep your cat indoors.
However, the real purpose of the study is to call into question the well established Trap-Neuter-Return (TNR) method for humanely decreasing feral cat populations through attrition. TNR is the practice of trapping, spaying and returning un-owned cats to a managed colony in the area from which they came. The authors of the report failed to understand that TNR is the only known means for reducing feral cat populations and as a result reducing the number of wildlife killed by feral cats.
The report deduces eradication is the best remedy for dealing with feral cats, not recognizing that decades of such efforts across the United States irrefutably demonstrates eradication does not work.
Feral cats have a strong survival drive, which means attempts to catch cats for extermination triggers a biological imperative to over-breed and over-produce. The consequences are exponential; rather than one litter of two or three kittens per year, a stressed female will have two or three litters of six to nine kittens annually.
Even if a community could remove all its feral cats, a phenomenon called “the vacuum effect” quickly lures neighboring cats into the newly open territory bringing with them all their annoying behaviors, including increased wildlife killing.
As we’ve seen time after time in locations all over the country, the end result of “catch and kill” is always the same: vacated neighborhoods are swiftly overrun again with feral cats fighting and caterwauling for mates, over breeding, and spraying to mark their new territory – sometimes leading to demands for stronger eradication efforts, which as we know, only exacerbates the problem.
The only way to save our wildlife is to reduce the number of feral cats. The only proven way to do that is through well managed Trap/Neuter/Return programs.