By Peter J. Wolf, Cat Initiatives Analyst for Best Friends Animal Society
It was typical of the dog park interactions one so often hears about: I thought to ask the pet’s name but not his owner’s. In this case, though, it wasn’t a dog park—or a dog. The unidentified cat owner and I were waiting, along with several others, outside a local spay-neuter clinic just before the doors opened. I was there with an unowned neighborhood cat and he was there with Raven, a large and handsome black cat taking in the scene from the safety of his soft-sided carrier. Raven, I was told, arrived one evening in the arms of a neighbor asking if the cat belonged to my new friend. No, he didn’t—but that was soon to change. And so, here they were.
As it turns out, Raven’s story is a surprisingly common one.
Since 1989, cats have overtaken dogs as America’s most common companion animal,  with an estimated 85.8 million pet cats in U.S. homes today compared to 77.8 million dogs. (Admittedly, the number of dog-owning households—54.4 million—still exceeds cat-owning households—42.9 million.) Our affections—and associated expenditures—aren’t limited to the cats we’ve welcomed into our homes, either.
An Alachua County, FL, survey, for example, found that 12% of residents feed cats they don’t own and assume are strays, at least occasionally. And a similar survey, conducted across Ohio, revealed a rate more than twice that: 26%, or about one in four residents. Perhaps most surprisingly, about 50-60% of those who reported feeding strays don’t even own a cat.
Millions of street cats charm their way into our homes every year. Indeed, APPA reports that 27% of pet cats are obtained as strays. Millions more come from sources that are also taking in strays, if only temporarily: shelters and humane societies (31%), friends and relatives (28%) and local rescue groups (6%). Some go on to become celebrities, including Internet icons Lil Bub, the late Colonel Meow, and Oskar and Klaus. And Bob, an orange tabby credited with saving the life of a homeless Londoner, a story told first in a best-selling book and then in a film of the same name, A Street Cat Named Bob. Even the Turkish film Kedi, with its large cast of feline characters—and subtitles—“has become a surprise hit” in the states, helping make it “the third highest-grossing foreign-language documentary of all time.”
And yet, calls for the killing of unowned, free-roaming cats on an unprecedented scale are growing. A highly publicized reference to removing all free-roaming cats by “any means necessary,” for example, attracted considerable media attention. And a Wisconsin hunter recently found himself at the center of a firestorm after bragging publicly about killing cats because, he claims, “the truth is feral cats are a huge problem.”
In fact, the “wildlife conservation” rationale for targeting outdoor cats rarely stands up to scrutiny. And the long-running arguments over the alleged impacts of outdoor cats only impede our efforts to craft sound public policy for their management. Even if we were to accept that all the claims about the impacts of free-roaming cats are true, what do we do to reduce their numbers?
Historically, this unenviable task has fallen to our local animal shelters. But we now know the traditional way of managing community cats—complaint-based impoundment followed, in most cases, by lethal injection—simply doesn’t work. This outdated approach has not only failed to produce any long-term population reduction, but is also wildly unpopular and costly—the poster child for failed public policy.
The science is quite clear—there are only two methods proven to reduce or eliminate the population of cats in a given area: intensive eradication efforts, or targeted sterilization efforts.
Eradication: Even more difficult and inhumane than you think
At 112 square miles in total land area (roughly the size of Tampa, Florida) barren Marion Island is largest island from which cats have been successfully eradicated. There it took 19 years to exterminate an estimated 2,100–3,400 cats, using feline panleukopenia, poisoning, hunting and trapping, and dogs.  During the final phase of the project, 30,000 day-old chicken carcasses were injected with the toxin sodium fluoroacetate (the use of which is both highly restricted and highly controversial in the U.S.) and distributed across the island.  In an ironic twist, Marion Island later became overrun with mice, threatening the very wildlife whose protection was used to justify the lethal control of cats.
The costs associated with such campaigns are almost as unpalatable as the methods involved, ranging from $1,000 per square mile (where non-target species are of no concern) to nearly $112,000 per square mile (PDF).  A program to eradicate cats and monitor seabird populations on Ascension Island (about half the size of Madison, Wisconsin) cost taxpayers nearly $1.3 million and “caused public consternation” as 94 of the estimated 661 cats killed were residents’ pets. 
Of course, small oceanic islands have little in common with the urban and suburban areas where most unowned, free-roaming cats are found in the U.S. The “closed” nature of island ecosystems, for example, mean that some species are likely to be more vulnerable to introduced species than, say, in Chicago, where “working cats” are seen as a desirable form of rodent deterrent. And let’s face it: even if a case for eradication could be made convincingly, the horrific methods employed and astronomical costs render any such campaign a non-starter in the U.S.
All of which makes the case for intensive sterilization campaigns a pretty easy sell.
The benefits of sterilization/vaccination campaigns
Across the U.S., implementation of trap-neuter-return (TNR) programs is on the rise, with thousands of unowned, free-roaming (“community”) cats humanely trapped, sterilized and vaccinated, and returned to the location from which they were trapped. (Some refer to these programs as TNVR to make explicit the vaccination component.) Sociable adults and young kittens are often adopted.
Targeted TNR efforts have been shown to stabilize and reduce the number of cats in an area as “colonies” decrease in size and number over time, with some eventually disappearing altogether. In Randolph County, North Carolina, for example, a long-term study documented a 36% average decrease among six sterilized colonies in the first two years while three unsterilized colonies experienced an average 47% increase over the same period. 
Other success stories include the Ocean Reef Club in Key Largo, Florida, where the number of “community cats” was reduced from an estimated 2,000 cats in the late 1980s to around 250 today, and Newburyport, Massachusetts, where the “wharf cats” once estimated to number 200–300 were eventually eliminated through TNVR. And research studies have documented significant reductions as a result of sterilization programs in a variety of settings, including university campuses,  an urban zoological park,  and a research hospital. 
Targeted TNR programs can also reduce nuisance complaints, protect public health (via herd immunity in the community cat population), and decrease operational costs for animal shelters.  Not surprisingly, these programs enjoy broad public support. Indeed, a 2014 survey commissioned by Best Friends Animal Society revealed that 68% of respondents preferred TNR for managing community cats.
Thanks to the heroic efforts of organizations such as the Found Animals Foundation and Alliance for Contraception in Cats and Dogs, it seems to be only a matter of time before a non-surgical sterilant for use in cats is available. And it will be a game-changer, especially for reducing in the population of community cats.
But until then?
In most contexts, TNR is simply the best option we’ve got. It’s better for the cats, of course, but also better for public health, for animal shelters and the communities they serve, and for wildlife. TNR is, in other words, sound public policy.
- APPA, 2013–2014 APPA National Pet Owners Survey, 2014, American Pet Products Association.
- Bester, M.N., et al., A review of the successful eradication of feral cats from sub-Antarctic Marion Island, Southern Indian Ocean. South African Journal of Wildlife Research, 2002. 32(1): p. 65–73.
- Bester, M.N., et al., Final eradication of feral cats from sub-Antarctic Marion Island, southern Indian Ocean. South African Journal of Wildlife Research, 2000. 30(1): p. 53–57. http://journals.co.za/content/wild/30/1/EJC117086
- Campbell, K.J., et al., Review of feral cat eradications on islands, in Island invasives: eradication and management, C.R. Veitch, M.N. Clout, and D.R. Towns, Editors. 2011, IUCN: Gland, Switzerland.
- Ratcliffe, N., et al., The eradication of feral cats from Ascension Island and its subsequent recolonization by seabirds. Oryx, 2009. 44(01): p. 20–29. http://dx.doi.org/10.1017/S003060530999069X
- Stoskopf, M.K. and F.B. Nutter, Analyzing approaches to feral cat management—one size does not fit all. Journal of the American Veterinary Medical Association, 2004. 225(9): p. 1361–1364. http://www.ncbi.nlm.nih.gov/pubmed/15552309
- Levy, J.K., D.W. Gale, and L.A. Gale, Evaluation of the effect of a long-term trap-neuter-return and adoption program on a free-roaming cat population. Journal of the American Veterinary Medical Association, 2003. 222(1): p. 42–46. http://avmajournals.avma.org/doi/abs/10.2460/javma.2003.222.42
- Mendes-de-Almeida, F., et al., Reduction of feral cat (Felis catus Linnaeus 1758) colony size following hysterectomy of adult female cats. Journal of Feline Medicine & Surgery, 2011
- Zaunbrecher, K.I. and R.E. Smith, Neutering of feral cats as an alternative to eradication programs. Journal of the American Veterinary Medical Association, 1993. 203(3): p. 449–452.
- Hamilton, F.E., Leading and Organizing Social Change for Companion Animals. Anthrozoös, 2010. 23(3): p. 277–292. http://www.ingentaconnect.com/content/berg/anthroz/2010/00000023/00000003/art00006
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This post forms part of the conversation about what to do about the growing problem of feral cats, which wreak large-scale havoc on birds and other wild species, according to numerous scientific studies. Other posts in this conversation include: