Aggression towards another cat when being approached can be a symptom of an underlying problem. However, always take aggressive episodes seriously. When approached by another cat, aggression may occur, leading to serious fights and possibly injuries to either cat – the aggressor or the victim. Other forms of aggression might be more subtle and you may not immediately notice them. Nonetheless, it may result in stress signs, such as not eating, not using the litter box appropriately, hiding or over grooming.
Even the presence of another cat, when not properly addressed, can evolve into serious aggression. It is important to assess and tackle any change in your cats’ 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 can occur when your cat is being approached by another cat of any breed, size, age, or gender. It can stem from many different types of stressors. The most common include fear, defense, territorial, redirected, status, play, pain, and discomfort. A fearful cat may exhibit dilated pupils, ears turning back, or a twitching tail. In this situation, your 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 their own separate areas. Don’t allow the aggressor to approach the fearful cat. Watch any interactions closely and only allow a cat to approach another one if they do not exhibit the signs of stress or aggression listed above. If you must separate two cats to prevent serious fighting, re-introduce them slowly when they are ready. Some cat-to-cat introductions go very smoothly. Others may take weeks or months before your 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 if you are working towards a positive long-term relationship. Being patient will pay off!