Introducing a New Cat to Resident Cats
Some cats are very social and they enjoy living with other cats, while others prefer to be solitary. If you are integrating a new cat into your home, be prepared to take time.

The best advice is to introduce the cats gradually and be patient! It takes most cats about 8-12 months to develop a friendship with a new cat. Others never become friends but instead, mutually avoid each other. Still others continue to fight until one of the cats must be re-homed.

If you are dealing with cats that have lived harmoniously with other cats in the past, the odds are probably good that they will adjust, however, it is impossible to predict if any two individual cats will get along. If the resident cat becomes aggressive when it sees other cats outside the home, you will probably have a difficult time integrating a new cat. There are no reliable guides for deciding the best matches among cats, except that male cats, if they do become friends, tend to spend more time close to each other. The individual personalities of the cats are more important than any other factor, including sex, age, or size. Be aware that the more cats you have, the higher the likelihood that you will have conflicts between the cats.

The first impression the new cat makes with the resident cat(s) is critical. If the cats display aggression, this may set the mood for their future relationship. For this reason, it is best to separate the cats initially. The cats should be able to smell and hear, but not see or touch each other. Each cat should have its own food and water bowls, litter box, scratching post, bed, etc.

Feed the cats near the door that separates them so they learn that coming together (even though they can’t see each other) results in a pleasant experience. Feed extra special treats near the door as well – tuna, salmon, cheese, chicken, liver, etc. After 2-3 days, switch the cats so they can investigate each other’s smell. This also allows the new cat to explore a different section of the home. Some behaviorists even suggest rubbing the cats with a mutual towel to intermix their scents.

After a few more days, play with the cats near the door. In particular, encourage the cats to paw at the toy under the door. Eventually the cats may play “paws” under the door with each other.

After a week or so, assuming you see no signs of aggression at the door (no hissing, growling, etc.), replace the door with a temporary screen door so the cats are able to see each other. Continue to encourage feeding, eating treats, and playing near the door, although you should start a few feet away from the door and, over a few days, gradually move closer.

The next stage is to permit the cats to spend time together. Supervise these interactions carefully. It is good to bring the cats together when they are likely to be relatively calm, such as after a meal or a strenuous play session. Keep a squirt bottle handy in case the cats begin to fight.

As the cats become more familiar with each other, allow for longer periods of time together. If one cat spends most of its time hiding or if one cat is continually harassing and pursuing another cat, you should seek the assistance of a certified animal behaviorist or veterinary behaviorist.

Pay attention to the layout of your home. Make sure there are plenty of hiding spots for your cats. Some cats like to sit up high, on shelves and on kitty condo perches. Frightened cats tend to hide under and behind things so make sure you provide for spots at floor level as well. Place food, water, and litter boxes out in the open so the cats do not feel trapped accessing these resources. Make sure you have a litter box for each cat and at least one extra.

The Importance of a Good Introduction
Planning to add a cat to your household? The introduction process is all-important.

First impressions can be lasting impressions for felines. In the wild cats take great care to prevent chance encounters with other cats through scent-marking behaviors. By “reading” the marked areas, cats can tell who was there last and at what time he visited the spot. The territory can then be used by different cats at different times of the day–the feline version of time-sharing.

In order to get your cat used to the idea of sharing the home turf with another feline, a gradual introduction is essential. Time and patience are the keys to successfully introducing a new cat into the household. The new cat should have a room of his own for a few days. Exchange the new cat’s bedding with that of the resident cat so that they can become acquainted with each other through the all-important sense of smell before they have the opportunity to see each other. Next, rotate rooms.

Let the new cat explore the rest of the house while the resident cat spends some time in the new cat’s room. When they are relaxed about this step, crack the door of the new cat’s room so that they can see each other, but can’t push the door open. Give the cats treats on both sides of the door. Two small toys joined with a several inches of string and slipped under the door will encourage parallel play.

When the cats are calm in each other’s presence, it is time to let the new cat out for a few minutes. The length of the visits can be increased gradually each day. This process may take a few days or a few months depending on the personalities of the cats. Usually it takes less time when one of the cats is under four months of age.

Throughout the introduction process, speak quietly and calmly to the cats. Praise them generously when they are tolerant of each other’s presence. Never scold or use harsh tones when they are together or they will associate unpleasantness with being near each other.

Give special attention to the resident cat as it is this cat’s territory that is being invaded and it is this old friend who is likely to need the most reassurance. Until they become friends, give the new cat loving attention only when the resident cat is not around.

If at any time the cats become fearful or hostile, return the newcomer to its room and close the door. A minor setback will not ruin the budding friendship, but a fiercely aggressive encounter will be remembered for a long time and should be avoided at all costs. Whenever you run into a problem, back up to a previous stage of the process and then move carefully forward again. Only you can determine the pace of the introduction process.

The time you spend gradually habituating your cats will eventually be rewarded with years of harmonious feline companionship.