Adding a new member to your feline family is often more exciting for you than it is for your current cat. Although they are loners by nature, most cats eventually learn to accept or at least tolerate newcomers. Because they are very territorial, the way you present the new cat to your existing cat can mean the difference between success or “catastrophe.”
The introduction process can take anywhere from 10-12 days for kittens and very young cats, up to 12 weeks for older cats. It all depends on the personality of each cat. Make sure to pay close attention to your “first” cat. This will help him feel confident that he is not competing for your affection.
Confine your new cat in a “safe” room until the introduction process is complete. It should be a small room, such as a bathroom or small bedroom, that your current cat rarely visits. Assemble him with a bed, scratching post, food, water, and litter box.
At first, your first cat may hiss and howl at the cat on the other side of the door. Just ignore it and walk away. Never punish him for vocalizing aggressively, it will only cause problems between the two cats. Be sure to praise and pet your first cat when acting calm around the new cat’s room.
After a few days, take a rag or washcloth and rub it on your new cat while you pet and play with him. Use a different rag to do the same for your first cat. At mealtime, place each cat’s scented cloth under the other cat’s bowl. This will help them associate the other cat’s scent with something positive: food. Giving them lots of small feedings every day will help them get used to the smell more quickly. Be sure to renew the scent of the rags every day.
You can then feed them closer. Keep your new cat in her “safe” room with the door firmly closed and place each cat’s plate on their side of the door. Make sure to feed them at the same time. Once you both eat without growling or whistling, you can move on to the next level of the introduction.
Lock your first cat in a room he likes to frequent, making sure he has water, his favorite food, and a litter box. Let your new cat out to explore the house. After a few hours, return her to her room and let her first cat out. He will probably hiss and complain when he smells the scent of another cat in HIS territory. Again, be patient and praise her when she acts calm. Repeat this activity at least once a day until both cats are comfortable.
Before allowing cats full access to each other, let them meet face to face in a safe situation. Use two hard plastic stops to block the door to the new cat’s room to open only 2-3 inches. Check that the door cannot be opened any further and that none of the cats can stick their heads out of the opening. The goal is to give them the opportunity to paw each other and even go nose to nose without the opportunity for full body contact. Feed each cat on their respective side of the door. Once they stop hissing or growling at each other, you can try playing with both of them in the same room.