The last few years have been a very exciting time for cat advocates because the new community cat paradigms are revolutionizing how shelters deal with cats. Problems can arise in fully implementing community cat programs, though, including ordinances that restrict trap-neuter-return (TNR) or return-to-field (RTF). Just recently we have had a threat to the TNR program in Washington, DC and a scare as to the TNR and RTF programs in Jacksonville, Florida. We never know when or where the bird conservationists are going to pop up and propose a restrictive ordinance to stop TNR and RTF, or try to persuade government officials to adopt a trap-and-kill program.
Community cat advocates are fortunate to have great sources of help and information such as Alley Cat Allies and the Million Cat Challenge. Peter Wolf’s blog Vox Felina has many articles deconstructing the research that bird conservationists cite as support for their trap-and-kill agenda. In addition to those great resources, I thought it might be handy to have a short guide to the true state of knowledge about feral and community cats today. Here are some facts that sometimes get buried in the rhetoric about free-roaming cats .
We have no idea how many free-roaming cats there are in the United States. In 2013, a meta-analysis of cat predation on wildlife that came to be known as the Smithsonian study was published by three conservationists.* The paper received a great deal of attention and has been frequently cited by bird conservationists in arguing for trap-and-kill programs. The authors admitted, however, that the number of free-roaming cats in the United States is not known. In their words: “No empirically-derived estimate of un-owned cat abundance exists for the contiguous U.S.” What this means in plain English is that no one has ever done an evidence-based study on the number of outdoor cats in the United States. The authors then went on to acknowledge that the guesses people have made as to the number of feral cats range from 20 million to 120 million. So if you are ever at a city council hearing and a bird conservationist says that “there are 60 million feral cats in the United States,” feel free to correct them by citing their own flagship study. The fact is that whenever anyone claims there are “x” number of feral or free-roaming cats in the United States, they are purely guessing.
Cats are a commensal species.** That means that they live primarily in and near human habitations, much like squirrels, raccoons, and opposums. Commensal species are dependent on humans for food and shelter. There is no evidence whatsoever that significant numbers of feral cats live in wilderness areas in the continental United States.
There is no evidence whatsoever that the number of unowned cats in the United States as a whole is increasing. In fact, the evidence we have indicates that the number of free-roaming cats is decreasing. Bird conservationists often argue that cats are an “invasive” species. It is true that the domestic cat is not native to the Americas, but there is no evidence that cats are an “invasive” species in the sense of rapidly multiplying and taking over habitats. Cats were introduced to the United States before the Pilgrims arrived, and if they were a classic invasive species the country would be chock-a-block with cats by now. Instead of increasing, cat populations in cities, measured by shelter intake and anecdotal evidence of the number of cats on the street, appear to have been declining for the last 75 years. And since cats, as commensal animals, live mostly in cities, then if cat numbers are declining in cities they are probably declining overall.
There is no evidence that cat predation harms bird species at the population level, or that cat predation has ever affected the survival of an endangered bird species in the continental United States. The authors of the Smithsonian study attached a supplemental table where they listed bird mortality by species as found in various studies. As Peter Wolf pointed out in a blog post on Vox Felina, of the 58 species cited, 57 are plentiful. One, the Northern Bobwhite, is listed as “near threatened,” but its status is attributed to habitat destruction and sport hunting.
No one knows how many birds a typical outdoor cat kills. Studies that have been done in the United States have found everything from 1.64 birds per cat per year to 186.47 birds per cat per year (see Supplementary Table S1 in the Smithsonian study). With such a gigantic variation in study results, the only reasonable conclusion we can come to is that scientists have not yet discovered how to set proper parameters for effectively measuring cat predation on birds in the field.
Owned cats kill fewer birds than unowned cats. Although the studies cited in Supplementary Table S1 of the Smithsonian paper are extremely inconsistent as to the number of birds killed by individual cats, the studies are very consistent in concluding that owned cats kill far fewer birds than unowned cats. Owned cats are fed, so it is not surprising that they hunt less. Feral cats who have a colony caregiver are also fed. Therefore, the Smithsonian study provides strong support for the argument that TNR, with ongoing colony care, will lead to less predation on birds.
The trap-and-kill methods pushed by bird conservationists have never been shown to work. In order for trap-and-kill to work, the generally accepted view is that at least 70% of the target population has to be killed, and this has to be repeated every two years. Because cats live mostly in urban and suburban areas, especially in alleys and vacant houses and outbuildings where they can find shelter, extermination programs would have to trap cats in people’s neighborhoods. I am not aware of any city that has ever tried a mass trap-and-kill program, and I cannot imagine how such a program would succeed. First, it would be very expensive because it would require the purchase of a large number of traps and the employment of a large number of people to set and monitor the traps and kill the cats. Second, catching feral cats is not easy, and the people who know how to do it would not be assisting the city. Third, the traps would catch more pet cats and small dogs than feral cats, and it would be very expensive to house those animals for return to their owners. Fourth, there would be many highly publicized horror stories of pet cats who were caught and killed by the trappers. Fifth, people who sympathized with the cats would sabotage the traps and would not allow traps to be placed on their private property. Sixth, the bird conservationists are not offering to fund or carry out these extermination programs themselves, and instead urge the cities to pay for it and to take the heat. Advocates should make sure that city officials see the contrast between TNR/RTF programs, which are paid for with donations and carried out by volunteers, and trap-and-kill programs which would have to be carried out by hired help and funded by the taxpayers. And we should use every opportunity to point out that bird conservationists who argue against TNR and RTF are trying to destroy existing programs without having any practical solution to put in their place.
Our message is not “just leave the cute kitties alone.” Bird conservationists often try to paint cat advocates as irrational and sentimental people, and they sometimes invoke or hint at the “cat lady” stereotype. They try to portray cat advocates as supporters of an untenable status quo. We need to make sure that government officials know that TNR and RTF are programs that are designed to change the status quo. In fact, the purpose of TNR and RTF is to do exactly what bird conservationists say they want, which is to reduce the number of free-roaming cats. Government officials love to find a middle ground on contentious issues, and TNR and RTF provide such a middle ground.
CITATIONS:
* “The impact of free-ranging domestic cats on wildlife of the United States,” Scott R. Loss, Tom Will, and Peter P. Marra, Nature Communications 4, January 29, 2013, doi:10.1038/ncomms2380.
** Terry O’Connor, Animals as Neighbors: The Past and Present of Commensal Animals (East Lansing, MI: Michigan State University Press, 2013).