What is Trap-Neuter-Return? Trap-neuter-return, commonly known as TNR, is the only method proven to be effective at controlling feral cat population growth. TNR involves trapping all or most of the cats in a colony, getting them neutered, vaccinating them against Rabies then returning them to their territory. The returned cats, who are eartipped to identify them as neutered, are provided regular food and shelter and are monitored by their caretaker for newcomers. Whenever possible, kittens young enough to be readily socialized and friendly adults are removed and placed for adoption.

TNR immediately stabilizes the size of the colony if at least 70 percent of the fertile adults are neutered. Neutering closer to 100 percent will result in a gradual decline of the population over time. In addition, the nuisance behavior often associated with feral cats is dramatically reduced, including the yowling and noise that comes with fighting and mating activity plus the odor of unneutered males spraying to mark their territory. Neutering dramatically lessens the often life threatening injuries male cats sustain when fighting over intact females. The cats tend to roam less and so become less of a visible presence. They may continue to provide natural rodent control, a desirable benefit in some communities.

On a community-wide scale, TNR also has several advantages. Foremost, the neutering of ferals lowers the number of cats and kittens flowing off the streets into local shelters or animal control facilities. This can have a substantial positive impact on euthanasia rates. For example, in San Diego, after only two years of county-wide TNR, euthanasia of cats dropped by over 40 percent. In San Francisco, after six years of a citywide TNR program, the euthanasia rate for all cats, domestic and feral, dropped by over 70 percent. The rate for domestic cats drops when there are fewer ferals because the lack of street kittens means less competition for spots in adoptive homes. Why bring in ferals off the streets when they can be maintained where they are, in a manner more befitting their unique natures?

Another potential advantage on a large scale is cost savings to animal control agencies. Traditionally, the cost involved with feral cats includes the time it takes for an officer to trap the cat, the expense of feeding and sheltering during the usual mandatory waiting period before the animal can be euthanized, and the cost of the euthanasia procedure. In contrast, the only cost involved with TNR is the neutering and vaccination of each cat. The rest of the work – trapping, feeding, and so on – is done by volunteers.

In a study in Orange County, Florida, over the course of two and a half years of a new TNR program, cost savings were found to be 47 percent (which came to over $109,000 in this particular case). TNR has the ability to mobilize large numbers of volunteers because it is life-affirming, which is in itself an advantage. Catching the vast number of feral cats now at large in many communities requires an army of volunteers, as animal control alone can rarely make even the slightest dent in the problem. That army is not going to step forward if the ultimate fate of the felines is to be killed. But if people know the cats will be released and then cared for, experience repeatedly demonstrates they will offer their time and effort. Feral cat caretakers are a devoted breed who will often do whatever is in their power to feed and protect their feline wards, The trap-and-kill approach can turn these caretakers and animal control officers into adversaries. TNR, on the other hand, mobilizes them into an enormous force for population control.

Failed Alternatives is perhaps the most significant argument in favor of trap-neuter-return in that not only does it (TNR) succeed in controlling feral populations when properly implemented – it’s the only known method that ever has! The typically out-of-control feral cat numbers in most regions should be testimony enough to the failure of the traditional “trap-and-kill” method. The reasons why it almost always fails in the long term are clear.

First, as you’ll discover if you become active in TNR, it’s not easy to catch all the cats in a feral colony. If there are a large number of cats, it can take several days and a lot of persistence. Animal control agencies rarely have the resources to make this kind of sustained effort. Instead, what normally happens is that animal control officers set some traps, catch some of the cats, and make a temporary reduction in the colony’s numbers. At this point though, nature kicks in. Feral colonies grow in size up to the number of cats their food source can support. Once the colony is reduced, the remaining cats overbreed until the ceiling imposed by the food source is reached again, and the temporary drop in population is quickly erased. Even assuming all the cats in a colony are caught and removed, that still won’t lower the population in the long run.

This is due to the “vacuum effect,” first observed by Roger Tabor in his studies of

You might ask, Why not remove the food source along with the cats and avoid the patterns just described? That’s much easier said than done. The food source might be the daily waste from a restaurant, garbage spilling out from a dumpster or scraps thrown out by those eating lunch in their vehicles at the local convenience store. Trying to control all this to stop food from being available is rarely a practical alternative. Some believe that depriving cats of food will force them to relocate in search of food. In fact, witholding food often has the opposite effect – they just come closer. Ferals are extremely territorial, and their nature keeps them from wandering off. Rather than leaving to find food elsewhere, they’ll encroach further into human habitations within their territory in search of sustenance. Depriving the cats of food is also obviously rather cruel, as it can result in their starvation.

TNR has the advantage of being humane because it respects the cats’ right to live and provides them with as high a quality of life as possible under the circumstances. It is also effective at lowering population levels, both within individual colonies and across entire communities. Other methods not only cost more; they don’t work. TNR is clearly the future when it comes to enlightened care of feral cats.