How to Stop Aggressive Cat Behavior Towards a New Cat

If you are thinking of adding a cat to your household, do so when you will be home during the day, every day, for about a week. This is a good time to plan a vacation from work, if necessary. Cats that were harmonious in a home may become temporarily unstable with the introduction of a new cat. Not all cats are aggressive toward a newly introduced cat. However, an aggressor cat in the household will try to block the new, victimized cat from any space it currently occupies. The aggressor may make overt attempts to remove the interloper. Physical characteristics of the aggressor include lowered ear position, pupil dilation, or outright attack. The aggressor may deny the victim access to cat boxes, food, water, and human attention. Male cats may mark territory with urine.

Things You'll Need

  • Spare cat box
  • Extra food and water bowl
  • Cat leash or harness
  • Cat collar
  • Bell for collar
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Instructions

  1. Existing and New Cat Integration Techniques

    • 1

      Separate the aggressor and victim. Place the aggressor in a remote environment within the home with food, water, and a cat box. The remote environment should be one less favored by the aggressor.

    • 2

      Allow the victimized cat free range of the environment outside the aggressor's defined location, such as favored sleeping places, sunny windows, or the owner's bedroom.

    • 3

      Allow a day of seclusion by the aggressor, then let him or her out under supervision only. At the first sign of aggressive behavior toward the victim or any other cat in the household, banish the aggressor again.

    • 4

      Allow the aggressor a period of solitude and when calm behavior is displayed, release the aggressor, but only if wearing a leash or harness.

    • 5

      Repeat these steps until some behavioral change is noted.

    • 6

      If the aggressor seems calm at this point, have him or her wear a collar with a bell on it to alert the other cats in the household to its coming presence. The other cats will learn to be warned of its approach this way.

    • 7

      When integration is achieved, reward all cats with treats, toys, and petting. This helps to ensure that all cats hold favor with the owner and are equal within the household or territory.