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Territorial Aggression in Cats

Cats may become aggressive due to territorial issues.

Cats in the wild are territorial creatures. They dislike having other cats in their area, and they spend a lot of time marking that territory and defending it. Our house cats haven’t lost that territorial nature, and while most cats living in multiple-cat households are able to work things out in such a way that they don’t often clash over territory, other cats resort to aggression toward the others.

How Do Cats Show Territorial Aggression?

Cats can show aggression based on territorial urges toward dogs and humans as well as other cats. Some clues that your cat’s aggression may be rooted in territorialism include:

  • Your cat spends lots of time marking his territory. You often see him rubbing his chin on things, making the rounds to patrol his area, scratching items in the house, and possibly even urinating on them.
  • The kitty hides and pounces on the object(s) of his territorial aggression. The cat may be aggressive toward all members of the household, only other cats, or only specific other cats. He may stalk, hide, and pounce on those that he considers threats to his territory.
  • The aggression happens in a certain area of the home. Although some cats defend an entire house as their territory, many are only aggressive when an “intruder” enters a certain area. This may be where the food is, where his favorite bed is, or some other area that is special to him.
  • A clear trigger may be present for the aggression’s onset. Cats that are territorially aggressive might not show it at all until there is some trigger that brings it out. This could be the addition of a new member to the household or a kitten in the home reaching sexual maturity.
  • A cat that has left the home to go to the veterinarian or groomer is attacked by the cat at home upon returning. Cats that have always gotten along may have problems when one leaves and picks up scents that are objectionable to the cat left at home. This can happen when a dog goes to the vet and returns home to be attacked by the cat, too.

What Can You Do About Territorial Aggression in Your Cat?

Feline territorial aggression can be particularly difficult to deal with. Here are some strategies for helping your cats overcome it as well as ways to avoid it in the first place.

  • Visit the veterinarian. If one of your cats suddenly becomes aggressive toward you or other humans or pets in the home, the first thing to do is visit the veterinarian to rule out a medical problem.
  • If you have multiple cats, work hard to ensure they each have access to enough resources. If cats feel like they have to defend their food, water, litter box, bed, or scratching post, they may become territorially aggressive. Be sure that each of your cats has their own stuff, so they don’t feel like resources are scarce.
  • Provide plenty of scratching posts. Scratching is one way that cats let out stress and mark their territory. If they have plenty of outlets for communicating with one another in the form of lots of great scratching posts, they should feel less of a need to resort to violence to make their point.
  • Have each cat spayed or neutered. Male cats that aren’t neutered are the most likely to exhibit territorial aggression followed by un-spayed females. Removing that reason for being aggressive is the first step in dealing with any territorial issue.
  • Separate feuding cats. Don’t assume that they will work it out. While this does occur sometimes, it’s more likely that the behavior will escalate, and the “victim” may be injured or become traumatized, leading to more unwanted behaviors.
  • Reintroduce cats very slowly, rewarding them for good behavior. This step can take quite a long time. Known as counter-conditioning, the process rewards the kitty for behaving calmly around the cat he used to attack. It requires short, supervised intervals of time together that grow gradually as the aggressive cat’s behavior improves.
  • Take care when you bring a new cat into your home. Don’t immediately allow a new cat to have full access to the home. Instead, keep the new kitty in a special room filled with everything she needs and gradually introduce her to the resident cat(s). Find step-by-step instructions here: “How to Introduce a New Cat to a Household that Already Has a Cat.”
  • Consult with a feline behavior specialist. A board certified behavior specialist can help you with the specific circumstances in your home.
  • Medication may be necessary. Some cats are given anti-anxiety medications while they are in counter-conditioning treatment. Your veterinarian is the best person to advise you on this. Never give your cat any medications without talking to your veterinarian first. Also, do not rely on medications to control aggressive behavior; you must also adjust the environment.

You May Also Like These Articles:

How to Introduce a New Cat to a Household that Already Has a Cat

STOMP out Problem Cat Scratching

Why Your Cat Scratches Some Areas of Your Home and Not Others

Special Cat Scratching Post Considerations for Multiple Cats

Stressed Cats Scratch More

Human-directed Aggression in Cats

Redirected Aggression in Cats

Cat Aggression: Why Some Cats Fight

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