Introducing A New Cat Or Kitten To Your Other Pets (part 2)

Written on November 26, 2012 by Staff Veterinarian

Cat to Cat Introductions

Introducing a new cat into a family with existing pets can be a difficult task, however, when it is done correctly, behavior problems such as inter-pet aggression, predatory aggression, fearfulness, anxiety and bullying can be avoided. Over the next few days we’ll be posting some guidelines, tips and methods for introducing a new cat into your home, given existing dogs, existing cats, or both. We hope this information will help as you negotiate the murky waters of a multi-pet household. Check out our post on how to select the right cat for your family, in case you missed it. Our final installment will focus on introducing your new cat to your resident dog.

Bringing Your New Kitten or Cat Home – The First Few Days

Provide a comfortable closed room for your new cat to spend their first few days.

  • Provide your cat with food and water dishes, comfortable resting spots, a new litter box, a scratching post, toys, and several hiding locations (cardboards boxes or tunnels made out of paper bags work great).  The litter box should be on the other side of the room from the food and water dishes since cats don’t like to eliminate where they eat.
  • When you arrive home with your new cat, take him directly to this room in a carrier, close the door to the room; set the carrier down and open the carrier door.  If your cat is nervous and won’t come out of the carrier, leave the room to give him time to adjust to his new surroundings.  If your cat has a blanket or other item that smells like his previous home, put that in the room with them to make them more comfortable.  Many cats will hide when they first come to a new house.  Don’t force your new cat to come out or push him beyond his comfort zone.  Keep this introduction upbeat and calm, allow him to get comfortable in his own time.
  • Sit on the floor and see if he will come out to say hello for treats or petting.  

This period of separation will give your new cat time to explore his new environment without the stress or interruption of your existing pets.  You will also have some special alone time with your new cat so you can work on building your relationship. During this time your other cat or cats may investigate the door area and you may hear some vocalizations.

  • Make sure to keep your resident pet’s schedule as close to normal as possible.  Cats are creatures of habit and if the new cat disrupts their routine, they will be paying attention.
  • After a couple of days, exchange items that smell like your new and your resident pets. Let your new cat smell your existing cat’(s’) scent and vice versa. A clean pair of socks or hand towels rubbed on each pet will do the trick. This will allow your pets (still separated) to safely familiarize themselves with each other’s scent.

Switching Territories – The Next Few Days

Watch your cats to see how they behave around the socks/scented items to get a feel for how comfortable they are.  Take your time with this step. If after the first few days, your resident cats are not acting upset or unusual, and the new cat seems to be comfortable, moving around in a relaxed manner and generally happy, start the next phase: switching territories.  This is important as cats are territorial, without this step, your new cat may view the room he is in as “his room”.

Make sure your pets (new and resident) do not interact with each other during the territory swap. Since cats are territorial it is important that all of your cats’ smells are spread throughout your home, and they can explore freely without real or anticipated interference of the other cat(s) in the home.  This will give them a chance to familiarize themselves with each other’s scents and make them more comfortable when it comes time to share spaces.

  • Let the new cat leave the room on their own while the resident cat is closed in a room, carrier, or other area.
  • Once the new cat is safely in another room (preferably closed in) you can bring the resident cat(s) to the new cat’s territory.  It is best to introduce one cat at a time to the newcomer’s room.  Start with the cat you think will get along with the new cat best.  In this case, put your other cat(s) in a separate room or carrier where they won’t see or interact with your new cat.  Switch territories a couple of times a day.

Feeding and Interacting

During the next phase you should feed your new cat and your resident cats simultaneously near the door to the room your new cat resides.  This will develop positive associations and relieve stress and they simultaneously enjoy their meals together with the safety of a door between them.  You can begin with the bowls at a comfortable distance from the door and gradually move them closer.  Once your cats are on opposite sides of the door eating comfortably you can open the door a pinch so they can see each other while eating.  Keep it open but don’t allow the space to be big enough for them to push through (you can use a doorstop at first).  Eventually you can put up a tall gate or screen to separate the cats at the door.

If this is progressing well you can open the door.

  • Have treats for both cats on hand and toys to provide a distraction.
  • Make sure the cats have hiding places to retreat to if they become scared.
  • Only introduce one cat at a time to your new cat (in order of suspected difficulty).  Do this for a brief time period and end on a positive note if possible.  Do this for several sessions and gradually extend the time for exposure.  If either of your cats become aggressive, hiss, or appear frightened, you should stop the introduction and go back a few steps.
  • After the cats are getting along for long periods you need only put your new cat in their room at night or other times when you cannot supervise them.
  • Once they are completely comfortable you can let them have the run of the house.

If Things Go Badly

  • Always do your best to end introduction sessions on a positive note.  In the case that you can’t or a one of your pets becomes very fearful or aggressive, separate them safely and go back a step or two.
  • Do your best not to let things intensify.
  • Progress slowly and don’t force anything on your pets.
  • During introductions you should be calm and upbeat.  Don’t act upset, scared, worried, or angry around your pets as this might make them suspicious of each other.

Note for New Kittens

If your new kitten is in the sensitive period for socialization (prior to 9 weeks of age) you may consider speeding up the introduction process if things are going well.  During this time your kitten is like a little sponge and will form lasting bonds with your other pets if they are willing partners.  If you suspect your kitten may be injured by another pet, supervise them carefully while they are together.  Also, just because your kitten is comfortable doesn’t mean your other pets are, don’t force this if your other pets aren’t willing or able to progress that quickly.

Useful Links:

Previous Post – Selecting your New Cat

Final Post – Introducing your new cat to your dog

For more information on personality types associated with different cat breeds, follow these links:

Animal Planet – Cat Breed Selector

Catster – Cat Breeds

Kathryn Wrubel, PhD has expertise in animal learning, memory, psychopharmacology and canine aggression.  She has volunteered in animal shelters and has experience fostering mixed breed rescue dogs.  Dr. Wrubel enjoys working with owners and their pets. She likes educating owners about the effects of their pet’s past experiences and genetic background on behavior. Dr. Wrubel is energized by her ability to help resolve behavior issues by teaching people and pets positive-based behavior modification techniques. She joined the IVG network of hospitals in February 2009.

Dr. Wrubel is available for appointments at IVG MetroWest and Massachusetts Veterinary Referral Hospital.

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