Feral Cat TNR - How Does It Work? I hope to answer that and other questions with my guest Alecs with Tucson Feral Trap Neuter Return - TNR Advocates. We'll discuss what TNR is, how it works, and the benefits of having a program like this in your community.  I also want to put out there that my guest Alecs let me know that they prefer to call the cats community cats not feral cats. The term feral is a dispositon describing their nature, which could mean they were born wild and have never had real human contact. TNR can be done on any outdoor living cat, not just feral cats.