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, and 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. This includes the yowling and noise that comes with fighting and mating activity and the odor of unneutered males' spraying to mark their territory. The cats tend to roam less and so become less of a visible presence. They continue to provide natural rodent control, a particularly valuable benefit in urban areas.

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. 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.

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