When an outdoor-access cat vanishes, it means that something unusual has happened to interrupt its behavior of returning home. There are several things that can happen to a cat to cause it to vanish, but here are the seven most common places where outdoor-access cats end up:
They become injured or are killed by predators.
Sadly, cats outdoor-access cats are at a higher risk of injury and death than cats that are kept as indoor-only house cats. Just because you don't see predators does not mean they don't exist in your area. Great horned owls and coyotes are usually nocturnal hunters, and they are both notorious for killing cats and small dogs. Also, in the wintertime, cats tend to crawl into the engine area of a car to keep warm, putting them at risk of injury or death when the engine starts.
They two-time and find a second family.
Some cats are actually "owned" by more than one family. I've heard of many cases where two families shared the same cat but never realized that they both loved and fed this two-timer! In one case, a stray cat showed up, was fed, and adopted by a family. They named her Tammy, spoiled her, and took her to vet and had her vaccinations. A few months later, Tammy vanished. Heartbroken, Tammy's owner put up flyers and conducted a door-to-door search for her missing cat. Upon contacting a resident in the neighborhood behind her home, Tammy's owner encountered a neighbor who looked at the photograph and said, "Do you mean Tiffany? She's in the back yard." Tammy/Tiffany, the twice-vaccinated cat who belonged to two different families, was sunning herself on the back patio. Raised since kittenhood by the first family, Tammy/Tiffany found herself in feline heaven, being fed twice a day and splitting her time between two homes.
They are removed (intentionally or unintentionally) from the area.
Although rescuing and saving an animal off the streets does not occur as often with cats as it does with dogs, many cats are removed from their territory by someone who intentionally wants to get rid of them, like an irate neighbor, apartment manager, or pest control company.
They become trapped or are transported away inadvertently.
Cats are curious. They will enter open cabinets, closet doors, shed doors, garage doors, camper doors, service vans left open, and just about anything that captures their attention. They often become trapped inside these places and then are transported out of the area. Many of these cats, due to fear, will slink down in silence during the transportation process. Drivers of service vehicles and moving vans rarely realize that a missing cat hitched a ride with them.
They get chased away and they establish a new territory.
Cats that are chased off by dogs or other cats are often too panicked to return home. Even though some cats have demonstrated the remarkable behavior of using the "homing instinct" to work their way back to their territory, many cats just don't. Being chased and even beat up by another cat is why some missing cats end up being found only a block or two away from home. Many of them are so frightened by a bully cat that they are pushed from their territory. In cases like this, frightened cats will not return home by themselves.
They end up at the shelter.
People who find a "stray" cat may bring it to the shelter. Many cats are taken straight to the shelter by neighbors (or pest control companies) who have humanely trapped them in order to remove them from the area. It's critical that you immediately search the local shelters for your cat if he disappears. Displaced cats often end up in the shelter weeks, and even months, after they were initially lost.
They are taken in by people who find them.
This does not happen as often as it does with people who find dogs, but many lost cats are adopted by people who find them. People who find a roaming dog typically realize that someone probably owns the dog and that it has not been living as a stray. But since cats can survive without direct care, people who find them often assume they don't already have a family.