Community Cats and Trap-Neuter-Return – FAQs

What is Trap-Neuter-Return (TNR)?

Trap-Neuter-Return (TNR) is an animal control management practice where community cats are humanely trapped, sterilized by a veterinarian, vaccinated against rabies, eartipped, and returned to the trapping location. An eartip refers to the small portion of the top of a cat’s ear that is removed during surgery (while the cat is under anesthesia) to indicate that the cat has been through the TNR process. Decades ago, TNR was performed mainly by caring individuals. Today, TNR is performed by individuals, shelter employees, veterinarians, and animal control officers alike.


Why should I support TNR?

TNR is the only effective method of reducing the community cat population. Trapping-and-killing, the old-fashioned approach to community cats, had been used by animal control agencies for decades without any success. Not a single community in the United States (or elsewhere) has reduced the community cat population through trapping-and-killing. It’s obvious now that lethal control doesn’t work.


Why doesn’t trap-and-kill work?

Lethal control has failed because it only temporarily reduces the number of cats in a specific area. Every habitat has a maximum population size that it can sustain. If part of the population is removed (through trapping-and-killing, or otherwise), the remaining animals breed until the population reaches its previous size. This occurrence is known as the “vacuum effect.” In other words, removing cats is only a temporary solution.  Animal control officers have to return every year to trap-and-kill new cats. It’s a never ending loop that wastes limited animal control resources. The former president of the National Animal Control Association, Mark Kumpf explains, “The cost for picking up and simply euthanizing and disposing of animals is horrendous, in both the philosophical and the economic sense.”

Furthermore, the way that local governments approach trapping-and-killing is particularly ineffective. Typically, animal control officers do not systematically trap cats. Officers usually trap cats after a community member calls and reports an issue. One or two cats are trapped on a particular street while the rest of the colony remains. Not only does this approach not reduce the population, it usually doesn’t even resolve the caller’s issue.


Are there any scientific studies supporting TNR?

Yes, many peer-reviewed scientific studies have demonstrated that TNR not only reduces community cat populations but also saves local governments’ money and improves community relations.

  • The 2016 study, “Association between a shelter-neuter-return program and cat health at a large municipal animal shelter” analyzed eight years of data from San Jose Animal Care and Control in California. It determined that the implementation of a Shelter-Neuter-Return program reduced both cat intake and cat euthanasia. Furthermore, financial resources previously spent on cat euthanasia were reallocated to provide medical care to cats with URI.[1]
  • An eleven year study of community cats at the University of Central Florida campus determined that the campus cat population decreased by 85% after a TNR program was instituted.[2] For years, the campus had unsuccessfully attempted to reduce the population through lethal control.
  • A 2002 study at Texas A&M University found a 36% reduction in the community cat population coupled with a decrease in nuisance complaints only two years after TNR was introduced.[3]
  • On the other hand, attempts at lethal control of community cats can worsen the problem. A 2014 study on the effects of trapping-and-killing on two cat colonies in Tasmania found significant increases in the cat population. Researchers found a 75% increase in population at one site while the second site’s population increased by 211%. Researchers theorized that the increase in population was due to new cats moving into the areas and an increased survival rate for the kittens born to remaining cats.[4]

The above studies clearly demonstrate that TNR is effective. But one of the best arguments for TNR is simple commonsense. Cities and counties have tried for decades to eradicate the community cat population through trapping-and-killing. Millions and millions of taxpayer dollars have been spent in this futile effort. Yet not a single community has been successful. If a city had succeeded, people who don’t support TNR would be shouting from the rooftops.


I don’t care about cats. Why should I support TNR?

TNR is not just about protecting animals. It simply makes good economic and policy sense. TNR is a win-win for everyone, even people who don’t like cats. It’s not only supported by the vast majority of animal protection organizations but also veterinary associations, animal control agencies, and local governments (from large, New York City, to tiny, Richland, Missouri). The leading veterinary schools, the University of California, Davis, and University of Florida, also endorse TNR.[5]


What if my city can’t afford to do TNR?

Over time, TNR will always be less expensive than methods that don’t work (like trapping-and-killing). In the short term, there are too many variables to say whether TNR is immediately cheaper than the city’s current approach. Luckily, governments have different cat management options.

First, communities that were historically unfriendly to TNR should openly encourage citizen participation. If a city has discouraged or even fined people involved with TNR in the past, efforts should be made to show that the city now supports TNR. The more people who do TNR, the more cats will be sterilized at no cost to the city.

Second, in virtually every community with TNR, at least some of the costs are covered by nonprofits or rescue groups. In some cities, animal control works in partnership with these groups and share costs. In other places, nonprofits do everything alone.  Clearly, the best approach is for government and citizens to work together on TNR. But this isn’t always realistic in places with tight budgets.

Third, the community cat guide from the University of California, Davis, and University of Florida, explain what shelters should do if TNR is too expensive or not an option.

… the other alternative to euthanasia of healthy cats is to simply not take them in to shelters until (and if) a home can be guaranteed. Shelters can schedule admission of healthy, adoptable cats…This allows shelters to focus on public safety and humane care by taking in dangerous, sick, or injured cats, and focus on lifesaving… Savings realized by not admitting, holding, euthanizing and disposing of healthy cats, can be invested in building TNR capacity for the future.[6]


Instead of TNR, why can’t we require people to spay/neuter their pets?

Mandatory spay/neuter legislation has not been effective in reducing the cat population for a few reasons. This is because those laws are aimed at pet cats. “Programs targeted at pet cats (e.g. low cost spay/neuter programs, legislation requiring that pets be sterilized, or humane education promoting responsible pet ownership) are unlikely to substantially affect the community cat population.”[7] Over 80% of pet cats are already spayed or neutered.[8] In contrast, less than 2% of community cats are spayed or neutered.[9] For these reasons, community programs aimed at pets have failed to reduce the flow of community cats into shelters across the country.

Second, the main reason that people do not spay/neuter their pets is because it’s too expensive. A mandatory spay/neuter law doesn’t change that. Offering free or low-cost spay/neuter options in your community is a much better way to increase the number of sterilized animals.


How can I reduce nuisances caused by community cats?

The first step to co-existing with community cats is to make sure the cats are sterilized. Spraying, roaming, and yowling are common behaviors exhibited by unsterilized cats. After the cat has been sterilized, these behaviors will lessen or disappear. Simple changes to your own behavior can also make your property less attractive to cats. For example, securing your garbage can lid with bungee cords protects against cats and other wildlife like raccoons.

There are also ways to proactively discourage cats from your property. Deterrents range from free, homemade solutions like spreading citrus peels to commercial products that use water or ultrasonic noise. For example, the CatStop Ultrasonic Cat Deterrent emits a harmless ultrasonic sound that only cats can hear. It deters cats from sensitive areas on your property such as your garden or child’s playhouse.

Your local TNR group or the internet is the best place to find specific advice about deterring cats.


I don’t want to spend my time or money on repellents. Why can’t I just remove the cats?

Community cats are already here, and we know trapping and killing doesn’t work. TNR is the best option available.

For the same reasons that the cat population hasn’t decreased after decades of trapping-and-killing, removing the cats yourself (or hiring someone to do it) will not solve the problem either. The vacuum effect means that if all the cats are removed, cats from neighboring areas will travel to the newly opened space and breed. More likely though is that you will not be able to trap and remove all of the colony cats. The cats left behind will continue to reproduce, and the resulting kittens will have a higher life expectancy because there are more food resources.


Does my city have to pass a law before doing TNR?

Generally, no. A law explicitly permitting TNR is rarely necessary. However, sometimes the animal control ordinance needs to be revised if there are obstacles to TNR. These obstacles can easily be resolved by providing exemptions for people engaged in TNR. Some communities choose to pass ordinances that state TNR is legal or that it’s the preferred method of cat management. For example, in Washington D.C., the animal control law states “The control of feral cats by a wildlife control services provider shall be consistent with the District’s policy in favor of trap, neuter, or spay, and return or adoption for controlling feral cats.”[10] These ordinances can be great because they provide protections for cats and caregivers far into the future. But if a restrictive ordinance is passed that puts lots of requirements on caregivers like registration or obtaining insurance, it can actually make things worse.


What’s wrong with requirements like mandatory registration of caregivers?

The goal of TNR is to sterilize as many community cats as possible. Forcing caregivers to reveal sensitive information about themselves deters people from fully participating in a community TNR program. Furthermore, in some places TNR was previously prohibited and the people who are being asked to register are the same people who were in trouble in the past. It’s no surprise that they would be cautious. Also, caregivers are providing an important community service, usually at their own expense. They are not criminals that need to be monitored.

With that said, recordkeeping and data from TNR programs are also important to demonstrate that TNR is working. One way to handle this is by having a non-government entity (like a rescue group) track willing caregivers and colonies. There should not be a legal requirement to register, but people should be strongly encouraged to do so.


If people want to take care of community cats, why can’t they keep them on their own property?

Community cat caregivers provide an important (and free) service to the community. Without a caregiver’s intervention, the community cat population would be even larger.  It is also not realistic to try to enclose community cats. There aren’t enough places to put them or people to take them.

As for community cat caregivers, it doesn’t make sense to blame the existence of community cats on the people sterilizing them. Some people think that if people stop feeding community cats, the cats will leave. This isn’t true. Feeding bans (prohibiting people from feeding community cats) have not decreased the community cat population because cats are bonded to their homes. If anything, the cats could become more of a nuisance after their consistent food source is gone because they might dig in people’s trash for food.



[1] Edinboro, C, Watson, H, Fairbrother, A. (2016) “Association between a shelter-neuter-return program and cat health at a large municipal animal shelter.” Journal of the American Veterinary Medical Association 248, no.3:298-308.

[2] Levy, J.K., Gale, D.W., and Gale, L.A. (2003). 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 222, 42-46.

[3] Hughes, K.L. and Slater, M.R. (2002). Implementation of a feral cat management program on a university campus. Journal of Applied Animal Welfare Science, 5, 15-28.

[4] Lazenby, B.T., Mooney, N.J., and Dickman, C.R. (2014). Effects of low-level culling of feral cats in open populations: a case study from the forests of southern Tasmania. Wildlife Research, 41, 401-420.

[5] Koret Shelter Medicine Program, “New Paradigms for Shelters and Community Cats.” June, 2015.

[6] Ibid.

[7] Ibid.

[8] Manning, A.M. and A.N. Rowan, Companion animal demographics and sterilization status: results from a survey in four Massachusetts towns. Anthrozoos, 2005. 5(3): p. 192-201.

[9] Wallace, J.L. and J.K. Levy, Population characteristics of feral cats admitted to seven trap-neuter-return programs in the United States. Journal of Feline Medicine & Surgery, 2006. 8(4): p. 279-284.

[10] DC ST § 19-1575







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