Almost every human community of any size has feral cats living nearby. In ancient days before domestication, the early ancestors of cats could often be found around our settlements hunting the rodents that were attracted to our granaries. What can I say, humans tend to attract mice!
In the United States, at least, all of these feral cats are actually descended from formerly domesticated cats who were either abandoned or lost over the centuries. While cats are not too far removed from their natural state, our domestic cats are not native to North America. Not only do feral cats often suffer tragically short and harsh lives living on their own, they also pose a real threat to native species in our local environment. In many places in the world, relentless human settlement and the accompanying introduction of non-native species into new ecosystems have nearly driven to extinction (or sadly already have driven to extinction) many species of birds and other wildlife.
But we can take steps to correct the problem we created. If you encounter feral cats living in your neighborhood, it is possible to humanely trap them and take them to local shelters for medical care. If found early enough, many feral kittens can become accustomed to human contact and will make good pets. Most feral adult cats cannot usually be put up for adoption, however. To address this situation humanely, many organizations sponsor "spay and release" programs that seek to reduce and someday remove altogether feral cat populations by preventing unwanted births.
One such program is the Feral Cat Spay/Neuter Project in Seattle. The Project states upfront "we believe that feral cats should not be killed simply because they were born without a house address" - a sentiment I strongly endorse. They offer a humane alternative to simply killing feral cats by effectively addressing the population problem at its root. Their web site offers useful information about how to trap feral cats humanely, and the Project offers free surgical procedures in regular clinics. If you live in another part of the country, there are many organizations that offer similar services in your area.
