If you recently brought home a new kitten thinking that it would provide companionship for your older cat, you may have been unpleasantly surprised at the result: your new kitten has turned into a fluffy ball of terror, attacking your older cat at every opportunity, while--far from being pleased with the new arrival--your cat hisses, swats or flees the scene. You may be relieved to know that not only is this situation perfectly normal--and probably temporary--but there are things you can do to discourage your kitten from sneak attacks on your cat.
Play Aggression in Kittens
Not only is your kitten exhibiting normal behavior by nipping, pouncing on and chasing your older cat, but these antics--called play aggression--are a vital part of its development. Kittens at play are really instinctively honing their hunting skills, on which their survival would depend if they were in the wild. A kitten that pounces on an older cat is merely reacting to the fact that the cat is moving, and everything that moves, for a kitten, is potential prey. A kitten normally practices its budding predatory skills on its mother and its litter mates, and--just like a puppy does--begins to learn bite inhibition and the limits of acceptable behavior from these first playmates. It is up to you, the owner, to finish the job.
Discouraging Play Attacks
Begin to teach your kitten acceptable limits by discouraging it from attacking your hands and feet. When your kitten goes after you or the other cat, practice the useful art of redirection by giving your kitten a large stuffed animal, which it can wrestle with to its heart's content. Provoke the kitten's interest in the toy by wiggling it provocatively along the floor. Distract your kitten from annoying the older cat by learning what behavior precedes a sneak attack--usually the kitten will crouch and waggle its rear end--and clapping your hands, whistling, or sharply saying "Ah! Ah!" If the kitten calls off the attack, praise it lavishly; don't forget to give attention to the older cat as well. If the kitten ignores you and harasses the cat anyway, squirt it with a water pistol. To avoid possible eye infection, don't blast your kitten directly in the face; flanks and shoulders are fair game, however. Some kittens don't mind being sprayed; if so, use a shake can or air horn. Keep offering positive reinforcement by saying "Good kitty!" whenever the kitten lets the older cat pass by unmolested. Reduce aggravation for the older cat by providing it with an escape route--either a room where the kitten is not allowed to go or access to something high up, such as a cabinet top which the kitten can't reach. Avoid leaving the kitten alone with the other cat. Above all, have patience. The odds are excellent that with time--and a few well-placed swats from the older cat--the kitten and older cat will learn to happily coexist.
Give your kitten an outlet for energy by tying a string to a fishing rod and twitching it unpredictably across the floor, throwing wadded-up bits of paper for it to chase (some kittens will bring these back to you) and sweeping floors and walls with a laser light or flashlight. If you can get both your kitten and your older cat involved in these games together, they will begin to associate each other with good times and fun.