Cats are curious little creatures. They’re completely domesticated but have retained a number of their wild instincts. Their domestication story is really interesting and sheds light on how this happened. One of the wild traits they’ve maintained is their fierce territoriality and with that the need to watch over it. These two instincts can lead to behavior problems, especially when an intruder is involved.
To a cat, their house and everything they can see around it is their domain. Cats will spend the majority of their waking hours peering through windows to watch over their territory. As long as this territory goes unchallenged, cats will be content to just watch the birds and lizards, but as soon it becomes compromised things can get a little tense.
Your cat’s individual temperament along with the behavior of the intruder will factor into just how harshly your cat will react. You might think that watching as the stranger hunts your cat’s territory would be the worse case scenario, but most cats are more upset by strangers looking in on them. This is called visual intimidation and it can be a difficult-to-diagnose source of behavior problems.
When your cat is struggling with maintaining their territory, they will likely begin showing territory based behaviors like they would in the wild. Inappropriate scratching is common, especially around the border of your cat’s territory. If your cat is strictly indoors, you might notice that your curtains and window and door frames are taking the brunt of this abuse. Scratching is both visual and scent based marking and in the wild can be very effective in maintaining border control. I have an article explaining what you can do if scratching becomes destructive.
Urine marking is a means of timesharing territory when the cat population in an area is too high for individual territories. Because cats aren’t social creatures and because they do their best to avoid conflict, they developed a message system of keeping out of contact when their territories overlap. Urine marking can tell other cats a surprising amount about the each other. In the case of territory guarding, urine marking can tell other cats the last time the resident cat was there and how often they return. For cats in the wild and at home, this helps to keep possibly dangerous encounters to a minimum.
Middening, or leaving behind unburied feces is another problem you might notice that falls in the timesharing category. It’s a less common communication tactic in domesticated cats but certainly sends a message to other cats of when they can be expecting the resident cat. Middening shouldn’t be confused with inappropriate toileting. One way you can determine the difference is if the poo is left out in the open and there was no attempt at covering it.
What You Can Do
If you feel like your cat is struggling with territory infringement, do your best to determine where their territory is being compromised. From there you should determine what things you can do to keep other cats from being seen or staring in on your cat.
Perches like sheds, fence posts, and cars can provide neighborhood cats with the perfect place to sit and stare at your cat. Since you can’t readily move any of those things to stop the cat from perching, you’ll need to try to obstruct your cat’s view. Closing your curtains to the problem won’t help since it’s so easy for your cat to get around them. Consider closing your blinds during the time the cat is most often around or keeping them out of that room.
If your cat’s upset with cats passing by, you can try cutting off their visual territory by arranging potted plants and patio furniture to limit how far they can see and thus claim. I’ve heard of other more intense strategies involving motion activated sprinkler systems. If you find that no amount of rearranging is keeping your cat from marking and emotional distress than those solutions might be worth looking into.