Indoor cat looking at outdoor cat through sliding glass door

The social behavior of cats can vary greatly from one pet to another. Some people do not believe that cats exhibit territorial behavior, while others have strong beliefs that they do. From my experience, I can say that I have certainly been called in many times to help people with their cat’s behavior issues after seeing an outdoor cat. Many people may not realize that their cats may be a menace to the neighborhood or to the neighbors’ cats. For example, I worked with a family that was mortified to learn at a neighborhood block party that the neighbors each had a story of how their cat was a bully. The cat would try to attack them in their own homes or cars when they tried to get the cat to leave! In another case, an owner was embarrassed to learn that her cat was going up to neighbors’ houses and begging for food. Almost everyone in the neighborhood had tried to adopt her cat at one time or another. The point is, owners of outdoor cats may not be aware of how much their outdoor cat is wandering or the effect it might be having on others.   While some people let their cats outside, other people choose to keep their cats indoors because indoor cats typically live longer lives than outdoor cats. Indoor cats are kept away from potential dangers such as other outdoor animals, cars and getting into potentially toxic or poisonous substances such as rat bait or antifreeze (unless of course they find these things inside their own homes). Those of us who keep our cats indoors know that sometimes indoor cats may be interested in watching outdoor cats walk through their yard and hang around outside their house. In some cases, indoor cats may become upset by the sight of strange cats close to their property. I have certainly encountered many cats who get so upset at the sight of an outdoor cat that they fluff out their fur, start yowling and hissing and then may turn on the closest living creature standing next to them, whether that’s their feline housemate, the family dog or the unsuspecting owner. It may sound funny but it is not a funny matter when your cats suddenly start fighting with each other after one episode of redirected aggressive behavior or when your cat starts to attack you or your dog every time he sees you after the incident. Some indoor cats may not become aggressive but still exhibits signs of stress. They may vocalize and pace back and forth close to the window where they last saw the other cat. They may also start to eliminate in inappropriate areas around the house. Sometimes outdoor cats may come to your property and deliberately spray around the outside of your house. If the outdoor cat sprays, odor molecules can sometimes be carried in through vents or open doors or windows. This can cause your indoor cat to become even more agitated. Sometimes, indoor cats will spray in response inside the house.

What can you do to keep an outdoor cat away from your property?

1. Few people ever consider this option but, remembering my anecdotes at the start of this article, it might be helpful to have a talk with your neighbors and let them know that you are bothered by their cat’s presence on your property. Some cat owners simply may not realize their cats are causing trouble on the neighbors’ property and may elect to limit their pet’s outdoor time or stop the cat from going out at all. 2. The use of remote deterrents can be very useful to help keep cats away from your property. The best devices are triggered by motion sensors. When a cat trips the motion sensor, the devices can emit a loud noise, shake or spray the cat with compressed air. There is a device that you can hook up to your garden hose and when the device is turned on, it will spray the cat with water from your hose. The deterrents should be positioned in locations around your property that the cats frequently visit. Some cats may just walk through a property and not approach a person’s house. However if your indoor cat is sensitive to the sight of another cat, he may still become upset seeing another cat in his yard. For these cats, setting up the deterrent at the entry point where they come into the yard is key to stopping the offending cat from crossing onto the property. Cats are predators to small prey but are prey to larger predators. They hate to be caught by surprise. So once the cat has been startled, it may take a few days or weeks before the cat will venture back. If you maintain the deterrents and the cat gets startled again, it may be a good long while before the cat comes back to your yard. 3. If you do not want to talk to your neighbors or set up remote deterrents, another option is limiting your cat’s visual access to the outside. Although this won’t stop your cat from hearing or smelling other cats outside, sometimes it is enough to calm the situation. Some people may choose to leave the blinds down. However this may not stop indoor cats from scratching at the blinds or squeezing their way between the blinds and window. Owners can purchase plastic static opaque window clings, which are easily found at home-improvement stores, and cover the lower half of the window to limit their cat’s view. This way natural light can still come in from the top half of the window, but your cat cannot see out via the lower half. Your cat can still look outside and see the sky and certain wildlife so the view will still provide a source of enrichment. Food puzzles, pheromone sprays and closing off rooms of the house are also management and distraction techniques that may help somewhat.

If All Else Fails, Get Help

Some owners have asked about the use of commercial products marketed as cat deterrents. These products typically call for the owner to spray a chemical around the house and/or property. I have not found a product that has been effective so I usually do not recommend this type of products. If the suggestions mentioned do not work for your cats then it is time to talk to your veterinarian, who may recommend a referral to a veterinary behaviorist or other certified animal behaviorist for additional help. A behaviorist may develop a plan to help manage the indoor cat and teach him to calm down. For example, behavior-modification exercises might help teach the cat not to get upset when he sees another cat or help repair the relationship between the owner and the cat or any other pets in the house the cat has attacked through redirected aggression. Sometimes, short-term anti-anxiety medication may help. More on Vetstreet: