Introducing cats to a new home


Cats are very location-oriented and can be very stressed by being moved to a new living location. This long-duration stress that the animal cannot escape must be given serious consideration as the type of hormones generated by harmful stress (stress that is intense and/or long-duration) can cause detrimental physical effects.

One form of harm from stress is the precipitation of illness. (And in extreme cases, some animals can even die from stress-induced conditions such as “capture myopathy” which can occur, for example, during the transport of a wild animal unfamiliar with being confined in a crate).

More commonly, there can be “invisible” damage. For example, animals undergoing long duration and/or extreme stress that they cannot escape may endure a small percentage of loss of function of one or more organs due to the effects of the circulating stress hormones. That will not be visible and so it is often presumed that “everything went fine”. But this kind of stress damage is cumulative; repeated severe and/or long duration stress during which the animal feels powerless can eventually result in a shortened life.

Add in to a cat’s health equation the additional stress if the cat is to be living with new people. And if there are other animals to get to know in the new home as well, it is very important that the introductions are done carefully and gradually. A difficult introduction, even if done carefully, can take as long as 6 months.

The good news is that many introductions can proceed much more quickly. Factors that can affect the difficulty or ease of an introduction are listed at the end of this article.

Managing the introduction of a cat to a new home

A whole new location, new people, and new animal companions to negotiate are overwhelming for most cats. To ease this, the following should be arranged
A single room should be allocated to the new cat for the initial adjustment period. The cat should remain in the room until he/she shows an interest in exploring further. Permit the room to be “home base” for the new cat until he/she feels very comfortable in all other parts of the home (Some signs that a cat is comfortable in an area: self-grooming, stretching out lying down, playing)

Scent is the most important sensory mode for cats. Place comforting scents in the new cats’ room.
-Provide cat bedding and other cat furnishings with the cat’s own scent on them (litter box, scratching posts, etc).

-Providing items with the former human companion’s scents on them is also helpful.

-Use Feliway cat pheromone spray per instruction in the cat’s living area.

Cat carriers will be useful tools for a complete introduction, so immediately
Start leaving a carrier out for each cat. Line it with comfy bedding, toys and treats so it becomes a familiar and comfortable place for all involved. This is a good thing to do for every cat anyway.

Principles for introducing cats to other cats

Reduce fear between the resident and new cats.

It is normal for cats (both the resident cat and the newcomer) to be defensive in the presence of an unfamiliar cat. Unlike dogs, getting cats to comfortably share territory takes more gentle work

Prevent aggression. Allowing chasing and/or aggression to occur between the cats sets up negative behavioral cycles between them that can take much longer to overcome than an aggression-free introduction will take. The “winner” can become more aggressive from “practicing” aggression and gaining reinforcement from winning. The “losing” cat can become overly submissive and fall into a role of perpetually being the victim. Both cats can be left with an undesirable --and probably unworkable—relationship with the other cat. Instead, provide opportunity for safe habituation and desensitization

Provide safe opportunities for habituation. Given the opportunity to gradually become used to each other without being able to hurt or unduly frighten each other, most cats will slowly calm in the presence of each other. The best tool to use is a see-through and smell-through barrier of some sort.** Maintain the barrier between the cats at all times in the early stages and at all times except for supervised introductions a bit later in the process. The more hrs each day that the cats have this safe exposure to each other, the more quickly they can calm down in each other’s presence.
( **a screen door, a panel of garden lattice across a doorway, stacked baby gates (3 high) in a doorway. ). A screen door wider than the door opening or a panel of lattice can be propped up by a pc of tall and heavy furniture on one side; fasten with self-sticking Velcro or hook/eyes on the other side. This makes it easy to unfasten and slide the barrier behind the tall furniture to enter/exit the room)

Permit social signals. Hissing and growling are signals that the cat is fearful, uneasy about the other cat. These signals should not be punished or scolded.

Promote calm. First of all, it helps a lot if YOU stay calm! 

To interrupt fear/hissing/growling you may be able to elicit a calm response in both cats without removing either of them from the location. That would then leave the cats with a positive association with the close presence of the other cat (Response Conditioning). If you cannot elicit and maintain calm in them, you can gently remove one or both from the location to go do something neutral (to cut short the negative feeling/memory). It is also fine to simply ignore their hissing or growling as long as the cats cannot hurt each other (due to the barrier).

Avoid any punishment, especially when the cats are in each other’s presence as they may associate the aversive experience with each other.
(Note: punishment of cats should actually always be avoided as it often worsens a situation, rarely makes a situation better, and can erode your relationship with the cat. Because it is a poor way to communicate what you do want from the cat, it is frustrating and stressful for the cat to endure even mild punishment. Better methods of managing cat behavior are available and proven effective)

Build positive associations between the resident and new cats

After you have a see-through, smell-through barrier in place, take notice of when the new cat seems calm in the room. Also watch for the cats showing some interest in seeing each other (as opposed to constantly hiding out of view of each other). After reaching those two milestones (calm, curious) you can begin scent blending by trading some of the cats’ bedding back and forth. The more the cats smell like each other, the easier it will be for them to accept each other’s presence.

At that point you can also start offering reinforcement items on both sides of the barrier at a distance that is comfortable for both cats to use the items (food, treats, toys “marinated” in catnip, clicker training sessions, etc.) After the cats are reliably comfortable at that distance for a day or so you can move the items or activities on both sides of the barrier slightly closer. Repeat this process by progressing at a rate that maintains calm in both cats.

When the new cat shows interest in exploring the new home, rotate the cats’ locations for short periods of time. That is, let the resident cat explore the new cat’s room while the new cat explores the rest of the home. Rotate the cats as many times a day as you and they like, but at least once/day. This gives all cats access to the whole home, prevents unnecessary territorialism, continues scent-blending of the cats, and allows the cats to see each other in a different setting.

Next Steps

After all of the above and all cats are reliably calm, even the toughest of intros should be ready for next steps.

Carriers, other “movable barriers” and no barriers


To expand on the rotation, you can start putting the new cat in a carrier and setting it in a room that is not otherwise visible from the other side of the barrier. Let the resident cat explore the cat in the carrier situation, which allows the resident to see the new cat in yet another part of the home. You can also switch who is in the carrier and who is roaming. Keep the sessions short enough that everyone is calm and/ or pleasantly distracted with treats. Over sessions, gradually lengthen the time until about 20 minutes is achieved.

At other times of the day, you can have the cats barrier-free during positive distractions--a meal, treat times, playtime.

At yet other times you can hold one cat while talking to the other. Take turns with them over sessions (no rotation during a short session).

Harness/ Leash. One of the cats may still have some tendency to want to chase the other (this may be just plain ol’ curiosity, a kitten overstepping his/her bounds and not “put into place” by the adult cat, or a cat with an previously established habit of chasing.) If that is the case, gradually condition the chaser cat to wear a harness and then gradually habituate that cat to the presence and pressure of the leash attached to the harness. Graduate to tying the leash to a pc of furniture or to your waist and make sure kitty learns how to not get tangled in the leash.

Now you have another tool for times when you want the cats to be barrier free but cannot watch them every minute. You can fasten one end of a long leash to a heavy pc of furniture or to your waist while you do your chores. Check periodically to make sure kitty is not tangled.

Equip your home for multi-cat living. Multiples of important “resources” for cats (food/water stations, prime resting areas, litter pans, toys, elevated perching areas) should be provided to prevent the need for competition. Cats are territorial, but they will peaceably “time share” if there is an equivalent other choice at a given moment.

By now most cats will be introduced nicely. This may have gone quickly and you may have even been able to skip some steps. You may even have been able to skip a lot of steps if these were “easy” cats (see following section re factors that can affect a cat’s ability to accept another cat).

But if you have a really tough case, you may need to continue to use the barrier when you are not around to monitor the cats. Prevention will always be your best tool for managing aggression. Squelching will not work and may have worse behavioral side effects. Changing the motivation is the only real solution. An insecure cat may take a long time to realize that a newcomer is not a detriment to his/her life and resources—which includes attention from you.

Always make sure your resident cat(s) get lots of attention during the intro of another cat (or other animal).

Some factors that can affect the rate of acceptance of a new home and other animals:

How well the cat is socialized to people (has had varied exposure during early development to kindly human handling)

How well the cat has been socialized to other cats. Ideally the cat has spent time with other cats during the first year of development so has learned how to be a cat and how to give and receive appropriate social signals with other cats.

Other experience a cat may have with other cats. A cat that has lived peaceably with at least one other cat in a home has a very different experience with other cats than a cat who has had to fight with other cats for food while living as a stray on the street. However, some street cats live comfortably in cat colonies with other cats, especially when there are colony caretakers feeding them.

How well the cat has been socialized to other animal species that will be in the new home. Ideally, when the cat was young, he/she had a significant amount of positive experience with the other species.

How much practice the cat has had with changing, complex environments. Cats that regularly experience life outside the home (in an outdoor enclosure, during regular car rides, walks, etc.) or cats that have other significant enrichment in their life that gives them a “bigger world” would likely be more flexible in their behavior than a cat who has developed in a small and/or unvaried environment.

Age of the cat. All else equal, the younger the cat the more flexible it will be in his/her behavior. Young animals’ neurological structures are designed to absorb new information and situations readily.

Behavioral Resources, Inc.
134 N.W. 59th Street
Seattle, WA 98107
(206) 784-8237