Alley Cat Allies has great information on trapping community cats.

Here are some particularly helpful tips for those just getting started.

Before you jump into Trap-Neuter-Return (TNR) action with your traps, it’s important to create a detailed plan so you know where to begin. Here are some steps to help you choose which cats to target, how to talk with community members, and how to prepare cats for trapping day:

Cats and the Community
For more successful results, it’s best to find a specific colony of cats or area with a large cat population and target them for trapping. The more cats in one location, the more cats that you’ll trap and get spayed or neutered. Once you finish the one area, you can move on to others.
Go out and talk to members of the community where you’re going to perform TNR. Don’t be shy! Hand out our educational flyers, brochures, and door hangers. You might end up finding people who feed cats but have never heard of TNR. Share how you are going to help these neighborhood cats and coordinate how they can help you by not feeding before trapping day to increase the likelihood of the cats going into the traps.

If you talk to anyone who doesn’t like cats (so sad!), explain how your TNR efforts are helping to stabilize and then reduce the cat population. We have some great suggestions on how to share with others the benefits of TNR in our Community Relations Resource Center. Offer your contact information in case neighbors have questions or issues arise so that you can help out.
When you’re out talking to neighbors, ask for volunteers to help you with trapping. Trapping is easier with more than one person, so find some willing volunteers and train them on trapping and how to use the equipment.

Preparing the Kitties for Trapping Day
Create a spreadsheet to log each cat and kitten you see to help you monitor the number of cats, their health status, and their approximate age. This will help you decide on the number of appointments and traps you will need.

For better trapping results, talk to community members to temporarily stop their own feeding routines. This will help the cats get used to eating at a certain time in the area that you want to perform the trapping in.

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