About the feral cat problem

There are hundreds of thousands of community cats, both feral and stray, living at large in US cities - and they reproduce quickly. When taken to shelters, ferals cats that were never socialized are often put down because they are unadoptable.

Learn more about this problem from the Humane Society of the United States (HSUS).

What is Trap-Neuter-Return (TNR)?

Trap: A feral cat is caught using a humane trap and taken to a clinic.

Neuter: The cat is spayed or neutered so that it will not reproduce. It is vaccinated against rabies, and its left ear tip is surgically removed to help identify it as a spayed/neutered.

Return: If the cat is unadoptable, it is released where it came from. Otherwise it is removed from the colony and placed in an indoor home.

Learn more about TNR from Neighborhood Cats or go to the learn to trap page to have your cats trapped.

Why you should conduct Trap-Neuter-Return (TNR)?
  • Prevent cat overpopulation
  • Reduce number of cats put down in shelters
  • Reduce community cats' unwanted behavior
  • Improve community cats' health
Learn more about the benefits from the ASPCA.

Why should you register your colony?

If you are a caretaker, registering will enable the Animal Rescue League to contact you if they receive a cat that they think belongs to you. It will also allow them to connect you with other caretakers in your neighborhood. .

Follow this link to register your colony.

How can you keep cats off of your property?

Use Cat Deterrents
The ASPCA has information on Keeping Cats out of Your Yard. The ARL's Community Cat Chat on September 9, 2014 will focus on deterrents and will include a demonstration of different types.

Conduct Trap-Neuter-Return
Reduce the number of feral cats. Learn more here.

About this project

This project is a joint effort by the Animal Rescue League Shelter & Wildlife Center (ARL), an open-door animal shelter and wildlife rehabilitation center in Pittsburgh, PA, and a team of students from Carnegie Mellon University's Human-Computer Interaction Institute. Their goal is to use technology to help improve Pittsburgh neighborhoods by helping communities address problems with free-roaming cats. For more information, visit the ARL website.

See coverage on the project by the Post Gazette.


Community cats have their homes within urban neighborhoods rather than in individual households. Some community cats are routinely fed by one or more community members, while others survive without human intervention. This term includes what is commonly known as feral and stray cats.

"Feral cat" is often used to refer to domestic cats that have never been sufficiently exposed to humans to become socialized. While some can learn to live as indoors cats, they require an experienced guardian and are almost always unsuitable for placement through a shelter or rescue program.

"Stray cats" were a fully socialized house cat at some point in their life, but have to live at large. Most stray cats are abandoned, rather than lost pets. Some strays are easily adoptable into a home, some find they way back to their owners, others may lose their bond to humans when they have to fend for themselves.

Trap-Neuter-Return (TNR) programs help control the community cat population by preventing them from reproducing. TNR also contributes to healthier conditions through a medical check and especially through a rabies vaccination.

A colony is a group of feral cats that live in the same area.

A caregiver is someone who feeds and provides continuing care for community cats, as well as ongoing TNR for the colony.

A trapper is someone who humanely catches community cats and returns them back to their home colony after they are spayed/neutered and vaccinated.