People who try to improve the welfare of outdoor cats are often confronted with the problem of overpopulation. When an existing colony of stray or feral cats suffers from a lack of food or is rapidly reproducing, the colony can be perceived as a nuisance by people who aren't involved in caring for the cats.

The solution to this problem is control of the colony's reproduction and is best accomplished by a stragegy known as trap-neuter-return (TNR). In a TNR program, stray and feral cats are humanely trapped, examined, vaccinated, and surgically sterilized by veterinarians. The cats are then returned to their familiar environment and their volunteer caregivers.

ONLINE RESOURCES

Both the American Veterinary Medical Association and the American Association of Feline Practitioners have created position statements on free-roaming, abandoned, and feral cats.

Several nonprofit organizations advocate on behalf of stray and feral cat populations. They all promote TNR programs. Alley Cat Allies is one of the leading resources for feral cat care in the United States. Their website explains the difference between stray and feral cats and provides extensive information resources on the history, effectiveness, and benefits of TNR programs. How to conduct a trap neuter return program.

The American Society for the Prevention of Cruelty to Animals (ASPCA) considers TNR to be "the only proven humane and effective method to manage feral cat colonies." The ASPCA website includes a page that discusses the past, present, and future of TNR programs.