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Does your TNR program work? Prove it.

Let's define effective TNR, gather data and quiet the critics

TNR programs have successfully helped reduce colonies with hundreds of cats to zero, but not everyone believes that TNR works. Are you able to demonstrate your TNR program's success to opponents armed with published studies saying TNR doesn't work? We know that targeted, non-lethal management is the right approach, and fortunately we have a growing body of published studies showing positive impacts.

Amazing success stories about trap/neuter/return programs abound. The Merrimack River Feline Rescue Society was founded on one: Having started with more than 300 cats in 1992, the last cat from that colony passed away in 2009. Through the diligent work of Neighborhood Cats, Riverside Park in Manhattan went from having more than 70 cats in 2001 to fewer than 5 today. There are countless anecdotal examples of how well TNR works, many with visual proof in the absence of cats at the sites. These examples help build momentum and fuel more TNR. But depending on who you ask, they don’t prove that TNR works.

It is well-documented that TNR reduces shelter intake and euthanasia, as Dr. Julie Levy’s 2014 study and many other researchers’ work have established. This is a major victory to celebrate, for all the good folks in the trenches fighting shelter pet overpopulation every day. But opponents to TNR, who want cats eliminated from the landscape regardless of the manner in which it is done, do not share our excitement that TNR achieves these outcomes. As discussed in my prior blog, they have just one goal—to reduce predation on wildlife.

In our work to protect companion animals, we can have many goals, including reduced cat intake, lower euthanasia rates, fewer complaint calls to an animal care and control agency—you can probably rattle off several more. But the one achievement that will support ALL our other goals is simple: fewer unowned cats in the community. So, in thinking about the big picture, I’m hoping those of you conducting TNR programs will share your thoughts on these questions:

Can you prove that your program works?


What is your definition of success?

Pretend I’m an opponent to TNR, and I believe there is no evidence that TNR works and that it has done nothing to reduce cat numbers. Keep in mind that in some places where TNR is not done in a targeted and effective manner, my belief, at least in part, reflects reality.

How would you counter my claim in a factual, evidence-based way?

Some opponents come to hearings, media interviews and public meetings armed with peer-reviewed, published, scientific studies that say TNR doesn’t work and cats kill birds and damage ecosystems. If these arguments are made in your community, will you be able to demonstrate your program’s success? Could you do it in a hearing about a bill introduced to prohibit TNR, speaking to legislators who expect data and science? Can you do it in a way that will stand up to probing questions and allow for replication?

Wildlife biologists, conservationists, veterinarians and others are actively testing their various hypotheses when it comes to community cat management. The result is a patchwork of scientific studies and data sets that paint an incomplete picture of what works. With many studies, the right questions aren’t being asked, or maybe assumptions are made that we disagree with—assumptions like all cats prey on birds equally (they don’t). We can and should pick apart every study, to see where it falls short, to see what new questions the results generate, to take issue with a skewed sample or poorly worded survey questions. At the same time, if we are to be taken seriously, it is extremely important that we use data and science to show the true impact of our work. This is an area where we have much room for improvement.  Our Cat-Friendly Communities track at Animal Care EXPO 2016 includes a class on “Smart TNR,” focusing on goals, how we achieve them, and how we show our success. I hope to see you there.

The good news is that there is an increasing body of published studies showing a variety of positive impacts. We just added a new section to our Managing Community Cats: A Guide for Municipal Leaders that summarizes several studies that can be used to paint a picture of why non-lethal management is the right approach. Check it out here and see what you think. We’ll be adding to it over time and would love to hear from you, so send us favorite studies, data sets and upcoming publications. It’s a solid starting point, but we need a much more complete library of evidence.

Now, we can all get stuck in the “my science is better than yours” debate. You’ve seen it before, in media articles, in legislative hearings and many other places where conversations about outdoor cats revolve around disagreement on how many cats there are, or how many birds they kill, rather than focusing on the more important issue of what we can do about it. In the courts of public policy and public opinion, these arguments by TNR opponents are not typically enough to thwart the good work of TNR programs, but it can significantly hurt by taking away precious time and resources that would be much better spent sterilizing and vaccinating cats. I acknowledge that current published science and data on TNR effectiveness is not ideal. I want that definitive study that shows a direct correlation between targeted TNR interventions and fewer unowned cats in that area. I know we will get there. We’re working on it, and hope you will, too.

I challenge each of you to think seriously about how we demonstrate the real impact of our work. Let’s evaluate our own programs honestly, be open to the possibility that there is a better way or more useful tools. Let’s look beyond our shelter statistics and the number of cats we’ve TNR’d to actual community cat population counts. Let’s gather the data that will allow us to confidently substantiate that TNR reduces the number of cats outdoors. Let’s show that targeted, strategic TNR works in the interests of animals, ecosystems and communities.

Because we know it does. We just need to do a better job of proving it.

About the Author

Katie Lisnik is the Director of Companion Animal Public Policy at The Humane Society of the United States, focusing on raising awareness and effectiveness of pet related public policy at the federal, state and local level. Priority work includes increasing interventions for and reducing community cats populations through sterilization and vaccination programs, ending the use of gas chambers in animal shelters, ending the abusive greyhound racing industry, as well as keeping more pets in their homes and preserving a strong human-animal bond. Katie has an MS in Animals and Public Policy from Tufts University; she is the Past President of the New England Federation of Humane Societies; and a former Board Member and advisor to the Maine Federation of Humane Societies.