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Avoiding Fights When Introducing a New Cat

There are steps we can take to lessen the risk of conflict.

Why do cats and cat owners remind me of a 1980s Lay’s potato chip ad? Because no one can stop with just one!

Thirty-one percent of households in the U.S. have cats and the average pet cat owner has 2.1 cats (AVMA 2012). We all have visions of happy kitty cohabitation, but in many homes, that simply is just not the case.

For a long time, cats were described as asocial loners that weren’t capable of cohabitating with other cats. We now know this isn’t the case. However, cats most certainly have specific social rules and species-specific ways of handling conflict that can be at odds with our human households. How does cat society work? What are the rules?

Ilana Reisner, DVM, PhD, DACVB
Source: Ilana Reisner, DVM, PhD, DACVB

Let’s take a look:

Cat society is a matriarchal society—that is, it is rooted in female bloodlines and bonding. It isn’t uncommon for related females to share space, resources, and even kitten-rearing duties. Males fight and defend access to territory and/or resources (food, water, shelter, access to the females) with their territory overlapping that of one or many females. If conflicts cannot be resolved, the losing cat—sometimes called the “pariah”—leaves the area, searching for a less competitive place to call home.

This is where cat society and human wishes collide. We choose random cats because they are cute, or have a nice personality, or they simply need a home, and then throw them all together, hoping they’ll be great friends. However, some cats aren’t buying it!

While female cats can get along, as a general rule, they are related to each other as aunts, daughters, and grandmothers. In such social groups, the females are not just a group randomly mixed together in pet homes. We also said that male cats are prone to be territorial and fiercely guard their resources. (Although neutering can lessen this risk, it is still a possibility among neutered males.) That can be a war zone if the “territory” is an 800 sq. ft. apartment. Recall as well that the way a loser cat handles conflict is by leaving the area. Hard to do if you are surrounded by four walls!

So what is a cat lover to do? The best bet is to set yourself and your cats up for success by trying to be mindful of cat society rules:

  • When you pick out your cats, try to think like a cat—pick two related females or a male and female cat. Although not guaranteed, it may reduce the likelihood of fighting.
  • Cats can be behaviorally flexible IF there is an abundance of available resources. In other words, what can your kitties fight over if there are two and three of everything they need? Be sure to provide multiple resources in multiple locations to reduce conflict (food, perches and shelves, hiding spots, litter boxes, water)—and no, two litterboxes side by side don’t count! The resources need to be in different locations and, when there is more than one level, available on each floor of the house.
  • Be familiar with cat body language so that you can be fairly certain about how your cats are responding to each other, allowing you to intervene in a timely manner if necessary. Cats are subtle creatures that can signal distrust and aggression with just a stare or a tilting of their ears. By the time a full-scale fight breaks out, aggressive interactions have often been taking place for months—we humans just missed the memo. You can learn about feline communication by watching the following webinar courtesy of Maddie’s Fund. (Also, keep an eye out for the soon-to-be-published book by the American College of Veterinary Behaviorists called Decoding Your Cat, the sequel to Decoding Your Dog.)
  • If you decide to add a new cat to the household, do so SLOWLY. Your new family member should be quarantined both for health and behavioral reasons to a separate room with a solid door. The cats can be allowed to sniff at each other under the door but not have physical contact. The newbie can be fed on one side of the door while the rest of the clan is fed on the other side. Gradually move the bowls closer and closer to each side of the door ONLY if you are not seeing any evidence of aggression (no hissing or reluctance to approach). Exchange towels or blankets between the newbie and the established cats to begin to develop a community scent. Swap out who is confined and who has access to the main part of the house—then and only then begin to allow your newcomer to come out and do so only under direct supervision. When you are gone, everyone needs to be secured in their own space. The introduction should take place gradually over a period of one month—and sometimes more.

If you don’t follow the above cat rules, how likely are you to have a problem? Unfortunately, the chances are pretty high. Approximately 50 to 60 percent of cat owners reported aggression when trying to introduce a new cat into their home. The moral of the story is that we should pay attention to cat rules, move slowly, and thus improve our chances of happily integrating a new friend into our home—because we all know that it’s tough to stop with just one!

Leslie Sinn, DVM, DACVB
Source: Leslie Sinn, DVM, DACVB

By Dr. Leslie Sinn, DACVB
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