Cat fights are scary, and can sometimes erupt even between felines who’ve been friends for life. Here’s what to do when the furs flies in your multi-cat household.

Janet’s 16-year-old cat Amber is not happy. A young Himalayan named Milo recently joined the family. Although Amber got along well with a previous cat, she is quite afraid of Milo and spends most of her time hiding under the kitchen table. Milo has tried to engage her in play but she is having no part of him. Rather than seeing his behavior as friendly, Amber is frightened by him. She is too scared to go to the litter box and has begun house soiling.

Amber and Milo illustrate one of several reasons why family cats may not get along. In this case, one cat wants a friendly and engaging relationship, while the other is frightened and defensive. Some relationships may not be as extreme as Amber’s and Milo’s. Some cats may start out playing, but then the play turns into fighting. Cats do not have ritualized play behaviors like dogs do, so misunderstandings can occur until the cats are more familiar with one another’s unique signals.

Other reasons for aggression between cats include:

  • Territorial triggers – Peggy has four cats, three males and one female, all littermates. One male, Teddy, is not satisfied with just keeping the other two males away from him; he seems intent on keeping them corralled in as small an area as possible. He’d probably be happier if he could drive them out of the house entirely.Teddy is showing territorial aggression. Studies show that in free ranging groups of cats, maturing males often disperse to form their own colonies. Indoor cats who take their territory seriously can begin to stalk, ambush and chase their feline housemates in a effort to gain sole possession of the space.
  • Personal space– Other cats are sensitive about personal space. Some may be able to co-exist as long as their bubbles of personal space are respected. The size of this bubble may be quite large for some cats, who may take exception if another feline comes within ten feet, while others can tolerate all but the closest encounters.
  • Redirected aggression– Nancy heard sounds of a cat fight in her kitchen. She found Topper and Blackie, who had lived together peaceably for five years, locked in a rolling fight in front of the door to the backyard, where a neighborhood stray was clinging to the screen. Agitated by the stray, but unable to get to him, the two cats attacked one another.
  • Who are you?– Rob and Linda were concerned about their cats Sam and Lucy. They’d always been best friends – until Lucy came home from a three-day stay at the veterinary clinic. When Linda let her out of her carrier, Sam took one sniff and started hissing. Lucy took exception to this greeting, took a swat at him, and the fight was on. Now the cats can’t be in the same room together; Linda and Rob have spent two weeks shuffling them between upstairs and downstairs to keep them apart.

Cats do not have ritualized play behaviors like dogs do, so misunderstandings can occur until the cats become more familiar with one another’s unique signals.

Clearing the air

Regardless of why your feline family isn’t getting along, the steps to take to help your cats are similar.

1 First, always check with your cat’s veterinarian. Amber, for example, might have developed a urinary tract infection either unrelated to Milo’s presence or caused in part by her stressful fear of him. Any condition that causes physical discomfort can make a cat grumpy and less tolerant of others.

2 You need to prevent future fights from happening. The more altercations cats have, the less they’ll like one another and the more aggression becomes their automatic way of responding to each other. You may need to keep your cats completely separated for awhile. It’s important to alternate confinement locations, giving each cat equal time in the largest part of the house.

3 Begin a behavior modification program. Feuding felines need an attitude adjustment. Initial emotional reactions of fear or aggression need to be replaced with friendly, relaxed behaviors. Start by creating a list of your felines’ favorite things. Take a lesson from The Sound of Music song – each cat should be able to remember her favorite things, and then not feel so bad in the presence of the other.

In one family I worked with, the price of peace was barbequed shrimp. For other cats, the price has been tuna, corn on the cob, cat treats or toys. Decide what kind of contact your cats can have with one another while remaining calm. For some, this might be just smelling each other on either side of a closed door. Other cats may be able to watch each other quietly from across a room as long as both are relatively still. Using a cat harness and anchoring the cats to stationary objects can prevent unwanted contact.

During controlled exposures, give your cats liberal offerings of their favorite things. Watch them carefully to be sure they remain relaxed and happy and aren’t becoming tense, agitated or fearful. Should this happen, choose an easier encounter that keeps the cats calm. Repeat these brief exposures five or six times a day, slowly increasing their intensity if the cats are doing well.

4 If you can’t find any way to reintroduce your cats that doesn’t cause one of them to act fearful or aggressive, you may need to contact your veterinarian for medication. If you aren’t thrilled with the idea of drugs, find a holistic veterinarian who can recommend alternative calming remedies.

Realistic expectations

Conflicts caused by redirected aggression among formerly friendly cats are most likely to have a good outcome. Territorial problems are the most difficult and have a lower likelihood of success. Many cats can learn to at least tolerate each other, but in the case of new introductions, it may require months of repeated, micro-managed encounters. In some cases, finding another home for one cat may be best for the welfare and emotional health of both.

A lot of multi-cat households have problems with conflicts and friction at one time or another. Keeping tabs on how your kitties relate to one another, how or why that dynamic might change, and stemming potential trouble before it escalates will help keep the peace.