Below are some common terms associated with TNR and their definitions.

Drop trap

A drop trap is a lightweight frame covered with netting made to catch feral cats. It is propped up on one side with a stick, and food is placed in the back. The trapper stands at a distance, holding a string attached to the stick. When the cats are eating, the trapper pulls the string, allowing the trap to drop, capturing the cats inside. The trapper then covers the drop trap with a blanket to calm the cat(s). The cats are then transferred to a humane box trap for transport to the vet clinic. Thanks to Laura Burns of Boston for this description of the drop trap. You can email Laura at HubCatsBoston@aol.com for more drop trap tips and techniques, or check out Drop Trap Design Bank for more details.

Humane box trap

A metal wire box rigged so that when an animal steps into it, the door closes, preventing the animal from leaving. These traps do not cause the animal any pain.


Eartipping is a technique of removing a small portion off the top of a feral cat's left ear. The procedure is performed while the cat is under anesthesia so there is no pain. The eartip is the universal symbol that a cat is from a managed feral cat colony and has been evaluated, vaccinated, and sterilized. Eartipping ensures that a sterile cat will not undergo unnecessary repeat trapping and surgery.

Feral cat

A feral cat is a domestic cat that has become antisocial (afraid of humans to a greater or lesser degree) after being lost or abandoned, or is a cat that has been born outside to stray or abandoned cats. A feral cat can also be the offspring of other feral cats that have lived in a more "wild" state for some generations. Feral cats usually live in family groups called colonies and can be found anywhere there is food. Feral cats can survive almost anywhere and are found all over the world.

Feral cat caretaker

A feral cat caretaker is a compassionate community volunteer who feeds feral cats, performs TNR, and provides long-term care and monitoring for adult feral cats that are returned to their original colony. Caretakers are men and women of all ages from all walks of life.

Feral cat colony

A feral cat colony is a group of free-roaming cats living in a specific geographic area. Prior to implementing TNR in an area, a feral cat colony consists of both stray and feral cats of all ages, including kittens. After TNR is completed, a feral cat colony consists of only adult feral cats.


In almost all cases, feral cats are better off being returned to their established outside homes after sterilization, to be watched over by caretakers. Cats bond with their territories and with other cats in their colony. Relocation is difficult, time-consuming, and often costly, and comes with no guarantee that the cats will stay in their new location. Alley Cat Allies (the national nonprofit clearinghouse for information on feral and stray cats) strongly recommends that all measures be taken to correct problems connected with keeping cats in their territories. If, however, compelling difficulties force the relocation of a feral cat colony, read Alley Cat Allies' relocation guide so you have the greatest chance of relocation success.

Stray cat

A stray cat is a domestic cat that strayed from home and became lost or was abandoned. Because a stray cat was once a companion animal, he or she may be able to be re-socialized and placed in an adoptive home.

Thanks to Alley Cat Allies for allowing us to use portions of their terminology list.