Not many things can be more exciting and heartwarming than bringing home a fluffy little kitten to introduce to the rest of your household. Until you realize, of course, that your older cat is feeling threatened and decides to assert himself by marking his territory and urine spraying -- yikes.
Even if everyone else in your home is fawning over the new fluffball, that doesn't mean your older resident cat will. Cats don't react well to change, and if your older male cat thinks the new kitten is going to disrupt his routine, he isn't going to like it one bit. When a cat sprays urine -- usually vertically -- to mark his territory, he is essentially communicating to the less dominant new kitten, "Back off. This is my turf, and don't you even think otherwise."
The anxiety and stress of the unknown is what typically causes cats to spray. If your cat is feeling tense -- and perhaps even jealous and ignored -- due to the arrival of the competition, you can do something about it. Don't allow him to feel neglected just because the new little one is around. Designate some special play time when you can bond with your cat and remind him he is important to you, too. Make sure to do this on a regular basis, even if it's just for 5 minutes at a time. Also consider getting him some catnip toys, such as stuffed animals. Catnip is a natural way to calm and relax kitties that are on edge! Treats also work. If you witness even a second of an interaction where your male cat is tolerating Junior, reward him with his favorite yummy treat. Positive associations go a long way.
Urine spraying is pretty icky -- no one will dispute that. The last thing you want is your entire home smelling like cat pee, from the walls of the basement to the walls of your bedroom -- ugh. Try to discourage the behavior by efficiently cleaning your male cat's preferred marking spots. If your cat has a favorite window for marking purposes, block it with something so he cannot reach it. Window blocking is especially helpful if your cat can spot other animals outside from it. Blinds can go a long way!
Cats are known for their independent streaks. Your male cat may be upset because he feels he no longer has his own space. Save yourself -- and your household -- a lot of unnecessary headache by assigning both of your cats their own spots -- away from each other. This means everything from having distinct litter boxes to distant beds.
If your tomcat's stressed-out behavior and territorial urine spraying won't let up no matter what you do, schedule an appointment with the veterinarian. Your beloved kitty may be able to receive medication that will help him manage his anxiety issues.