introducing a stray to rez cats

Question
Hi. I have 2 resident cats, both DSH, one is 2 years old, the other 5. Last sunday, March 16, I found a stray kitty in front of my building. She was very sweet so I took her in. I kept her in my bathroom for four days, named her Isabellal and took her to the vet (she is negative on feline AIDs/Leukemia and FIP. But she does have roundworm and was doused on March 18). On thursday, I moved Isabella to my bedroom and she loves it there. She has since learned to use her litter box.

Isabella is a very very sweet kitten. However, she hates my other cats (who are  in the living room, kitchen and bathroom). When she was in the bathroom, she would moan, hiss, hit the door, and take swipes at them under the door. Now that she is in the bedroom, things have calmed down a bit. The cats can be by the door and she doesn't hiss or run at the door ALL THE TIME. Now she just ignores them as she suns herself. But if she happens to be by the door she will hiss, moan, yell and extend her arms under the door to hit them. My rez cats are curious, very interested but very scared. Yesterday, Saturday, I did open the door a crack and let Isabella see the other cats and smell them. She hissed and jumped at them. Same thing today.

But today, sunday, Isabella did sit in front of the door and stopped hissing for a few minutes with her front paws under the door. However, she still hisses at them a lot. I have tried rubbing my T-shirts on the resident cats and then giving them to Isabella. She loves to lie on them but otherwise it doesn't seem to help.

I was hoping to put in a wire gate so they could all see each other but think I will wait a bit. What now? How long will this all take? The last cat I introduced only took 4 days to get along with my resident cat. But she came from a shelter.

Thanks for your help.

Answer
Morgaine,

Introducing new cats is usually a much longer process than four days. Generally I recommend that you isolate the new cat from the resident cats behind a closed door for 2-3 weeks. The reason that I recommend such a long quarantine period is most obviously to make sure that the new kitty is not carrying any contagious viruses or infections. You should know that ringworm is extremely contagious both to you and the other cats. Another reason that I generally suggest a quarantine period is so that the cats have an opportunity to get acquainted with each other's scents. Cats are fairly territorial and they don't like change so I generally suggest that any changes be as made as gradually as possible so that the kitties don't become upset and show their displeasure with less than acceptable behavioral issues. You can (once the ringworm is completely gone and has been double checked by the vet to confirm that she is no longer contagious) switch up the bedding between resident cats and the new kitty on the block. At this point hissing, growling and swatting are perfectly normal. Things will calm down once they get used to each other. It will take some time for all of the cats to adjust to each other. I would suggest that you try a homeopathic remedy called Bach's Rescue Remedy. This is a blend of flower essences designed to help overcome trauma, fear and anxiety. I would recommend that you start off at a dosage of about 7-9 drops in fresh water each morning. You can also give this to your resident cats, if they are a bit anxious about the new arrival this will help them to overcome it. The nice thing is that this remedy is very safe and gentle and it tends to work well in many cases. In fact I have heard of some veterinary clinics in Europe that tend to keep a bottle handy so that if an animal comes in traumatized and beginning to go into shock the vet will be able to get a clearer assessment while alleviating fear. If your new kitty in town has had any bad experiences with humans or other cats this will help her to be more laid back with the changes in her life. You do have to admit that going from life as a stray on the street to integrating into a nice warm, safe home where there is plenty of food but other cats is a rude shock. Just so that you are aware many times stray cats will be very territorial and some are very aggressive about defending what is theirs. You may find that with the Rescue Remedy this little kitten calms down somewhat and once the 2-3 weeks of isolation are finished there may be some posturing in the form of hissing and growling a bit, there may even be a few token swats here and there. As long as things aren't getting overly violent I would suggest that you stand by with a squirt bottle and a toy like a kitty tease to help them overcome the initial grumpiness. As I mentioned, the behavior you are seeing is very normal, most cats are more territorial than the kitty you introduced from the shelter. As soon as the vet gives you the all clear in terms of health you can slowly start to introduce the new kitty to your resident cats. It generally takes about 3 weeks for most cats to draw their boundaries and become comfortable with each other. All in all, 2 weeks of confinement for the new kitty (or until she is no longer contagious according to your vet) should be enough to introduce your family members. It will take a week or two for the cats to become comfortable with each other so be prepared that there may be some initial grumbling amongst the cats for a short period of time. Good luck with your new family member. If you have any further questions or concerns, please do not hesitate to contact me again, I will certainly do my absolute best to help you with any issues that may arise.