August 2019

Audience: Executive Leadership, Foster Caregivers, Public, Shelter/Rescue Staff & Volunteers, Veterinary Team

Aggression between cats who live together is fairly common. Some fights are obvious, and some can lead to serious injury. Other fights are more subtle, and you may not immediately notice them happening. The conflict between your cats can result in other signs, such as not eating, not using the litter box appropriately, hiding or over grooming. If you notice these signs in one of your cats and can't find the cause, aggression between household cats may be a serious stressor in the home.

Even mild forms of aggression, when not properly addressed, can evolve into serious aggression. It is important to assess and tackle any change in the cats' interactions and behavior right away. To address aggression, work with a professional who can look at the context in which it happens. Never use punishment as a training technique. It will not work and will only hurt your relationship with your cats.

Pay attention to your cat's body language. Aggressive behavior between household cats can be seen in cats of any breed, size, age, or gender. It can stem from many different types of stressors, including fear, defense, territorial, redirected, status, play, pain, and discomfort. Intense play between familiar cats can also quickly turn to aggression. A fearful cat may exhibit dilated pupils, ears turning back, or a twitching tail. In this situation, the cat may growl, hiss or swat at the other cats. Your cat may appear nervous, frightened and startle easily, trying to run and hide. A more offensive aggressive cat may have their ears back, constricted pupils, and their tail may be up or down with fur standing on end.

Always separate fighting cats to prevent injury. Do not reach in between two fighting cats. Safely confine each cat to its own separate area. Watch their interactions closely when they are together and only allow them in the same area if they do not exhibit the signs of serious aggression listed above. If you must separate two cats to prevent serious fighting, re-introduction can take a long time. Some cat-to-cat introductions go very smoothly. Others may take weeks or months before the cats learn to co-exist with each other. The best thing to do is to go as slowly as necessary-don't rush the introduction. You are working towards a positive long-term relationship; being patient will pay off!

This document created by the San Francisco SPCA with a grant from Maddie's Fund®.