If the cats had previously gotten along but have suddenly become enemies then redirected aggression may be a possible cause. One cat may have spotted an unfamiliar animal outside and redirected his aggression toward a companion cat. If one cat visited the veterinarian and then was attacked by his feline companion upon returning home, then that might be territorial/non-recognition aggression. There are many types of aggression and many causes so you need to sharpen your detective skills in order to uncover the trigger.
Make Some Changes to the Cats’ Environment
When the relationship between the cats is tense but doesn’t seem serious or dangerous, then you may be able to begin a behavior modification program to help them feel more at ease with each other. This involves creating an environment that inspires security as well as doing some behavior modification. Just wishing that the cats will get along or punishing them for reacting to each other will do nothing but continue the downward spiral. It’s time to make some changes in the environment and create positive associations.
Sharing Isn’t Always a Good Thing When it Comes to Cats
Look at the cats’ living environment and see what you can do to create more safe zones and security. For example, perhaps the cats have been sharing one food bowl and you notice they tend to compete for access. Give each cat his own bowl in that case. Another thing to look at is the litter box. Have the cats been sharing one box? The rule of thumb is to have the same number of litter boxes as you have cats. In the case of litter box issues or if there’s any tension between cats then the rule changes to having one more box than you have cats. It might be time to place another litter box in the home. Location of the box will matter as well so place that other box in an entirely different room. This way, one cat won’t have to cross the other cat’s path to access the box.