Introducing 2 cats that are used to living alone

Question
Hello Holly,

My boyfriend and I have decided to move in together. We each have a cat that has lived independently, but are hoping that with proper precautions and research, we will be able to allow them to live together.

I was hoping you would be able to provide me with suggestions and training tips on how to prepare both cats separately prior to the move.

Background on each:
My cat, Marley, a 2 yr. old female domestic short-hair that was found outside i rescued her at 5 weeks and hand-fed as a kitten. Marley is up to date with all of her shots, and is spayed. Marley still has her claws. Marley is self-fed, solid food. She was left behind by her mother, and I would assume that because of that situation, explains why she treats me like her mother. Marley follows me everywhere, and is always in the same room as me. Marley can be aggressive. At one point I was living with my mom, who has three cats, and tried to properly introduce Marley to my mom's three cats. I placed Marley in a carry crate and allowed the other cats to sniff her out. Marley spit and hissed, which I understand is natural.

My boyfriend's cat: Shadow, a 4 yr. old male domestic short hair. Shadow is neutered and has his claws. He adopted Shadow as a kitten. Shadow is overweight and on a strict diet. Shadow is aggressive, and would definitely dominate Marley. When there are many guests over Shadow will become territorial and hiss and claw at guests that try to pet him. He is friendly with me, because I feed him.

In your convenience, please provide me with any suggestions to make this living arrangement work. As I mentioned, the cats are currently separate, and any information would help prior to the move in.

Thank you for your time!  

Answer
Hi Jessica,

Congratulations on moving to the next step!  This is basically the slow and sometimes painstaking process you would go through with them.  Of course, when first getting another animal, you should keep the resident animal in its own safe space/room and let the new animal adjust for at least a week.  Get the new cat, feeding routine, and develop a bond before you even begin the slow introduction process.  After a week, place a towel where both animals like to sleep and then switch them so that they get used to each others smell before they even meet face-to-face.  After a few days of sleeping with the other towel, let them merely see each other at a distance.  Keep this short and brief, and make sure to end on a positive note.  Then, let them meet the same way you did before, have each cat in a carrier and set them beside each other for 10-15 minutes just so they can get used to each other's smell and presence.  Then remove and put back in their separate areas.  Then try  having one cat in a carrier and the other out and letting them be around each other that why.  Then do the same with the other cat in the carrier. There will be hissing and growling, and it's important not to scold the cat.  She is only saying 'I'm uncomfortable' or 'I don't trust you'.   This will take time, but the slower you make the process, the easier it is on both.  Start with letting them be in the same room and get accustomed to each others' smell and presence before allowing them both to be together in the house.

When you first introduce them not in a carrier, do so by feeding in the kitchen with them about 8-10 feet apart,  praise them if they are good and don't growl, and put them back.  The more you practice this, the better they'll do.  Don't ever leave them out together unsupervised until you have supervised their interactions enough to know you can trust them together (no incidents that would require your discipline).  Don't ever discipline by being physical or spraying with a water bottle.  Use a command word (I use 'shht) in a sharp, stern tone to stop unwanted behavior, then praise (pet and talk sweetly to) when they do what I want.  I know this can sound simple, but with repetition and consistency, it works.  Please let me know if you have any other questions.

Best regards,
Holly Martin
Cat Care & Behavior Specialist  
Texas A&M University
B.S. Animal Science