Cats have an incredible sense of smell. They can easily identify the odor of catnip when its concentration is 1 part per billion! Kittens are born deaf and blind but their sense of smell is already sharp and working. Within one day after birth, they can distinguish between their own home and another. They also lay claim to their own nipple and suckle from it exclusively. They know which one belongs to them by its unique smell. A 3 week old kitten placed 3 feet away from his home base will be lost if he can't smell his way back, even though he can see his mother and litter-mates!
Smell is vital to recognition. Most of us witness this phenomenon when we take one of our cats to the vet. Upon returning home, the cat is growled and hissed at and occasionally attacked by the cats that stayed home. They don't recognize their buddy returning home because he smells different. It's as if a new and strange cat has walked right into their home! A mother cat will even kill her own kittens if they should suddenly smell foreign.
Cats have scent glands along the tail, on each side of their forehead, on their lips, chin and on the underside of their front paws. They use these glands to scent mark their territory. Every time your cat passes by the refrigerator or the sofa and rubs up against it, he is saying, "This is mine. This belongs here. I belong with these things." When your cat scratches your furniture or his scratching post, he is also leaving his scent there from the glands in his paws.
Your cat will rub up against you and other companion pets for a scent exchange. While depositing his scent on you, he is also picking up your scent, which he will carefully lick and taste off his fur. (And we thought he was just grooming himself!)
If an indoor cat accidentally gets outside or if you move to a new location with your outdoor cat, it is very common that they will become lost - even if they are only 10 feet away from home. If they have not had the opportunity to scent mark their outdoor territory, they will not know where they are or how to return home.
Cats that are not adequately socialized as kittens can react badly to changes in their environment and intrusions of unfamiliar smelling objects, people or animals. A new piece of furniture can be viewed as an invasion of their territory. Some cats will hide from it for days. Others will immediately rub up against it to scent mark it. And some cats will feel so threatened that they will go to an extreme form of scent marking - urine marking.
Once a cat has urine marked, the scent must be immediately and thoroughly removed. We may clean it to our nose's satisfaction, but your cat and his keen senses will still be able to smell it. Remember the cats sense of smell is ultra sensitive. Your male cat may smell a female cat in heat from blocks away. The scent may come wafting in through an air conditioning duct or fireplace vent. If you move to a home where another cat has already left a strong scent, your cat may mark over those areas. Some cats will even attack their owner if the owner comes home with the smell of another cat on his/her clothing!
Cats are territorial by nature and they identify their territory by scent. The more you can socialize your cat as a kitten, the less likely this problem will occur in adulthood. Keep this in mind when moving with your cat, boarding him, taking him to the vet or groomer, bringing home new furniture, or bringing home a new friend.
Try to make your cat feel as non-threatened as possible by using familiar scents. For example, before bringing in a new piece of furniture, rub it down with some of your cat's bedding or even your own bedding.
If you have a veterinary appointment, take both cats even though only one will be treated. If one cat has a prolonged stay, then before bringing him home, have him groomed to wash away the peculiar smells of the hospital. In addition, rub kitty down with a towel that your other cat has been sleeping on recently.
When moving, you can help make the transition smoother for your cat by applying the same principle. Set up one room in your new house to be as similar to kitty's favorite room in your other house. Take along that old sofa even though you were planning to discard it. Kitty needs it now and you can always dump it later when he has made the adjustment to your new home. Bring kitty straight from your old house directly to this special room. Once he feels comfortable and the rest of your house is in order, then let him out. But don't let him go outdoors until he really accepts and feels at home indoors. Then allow him short supervised outings in your yard. Never leave him unattended until he has become familiar with his new outdoor territory.
Another suggestion: if your new residence had a cat living there previously, it recommended that you have the carpets, drapes, etc thoroughly cleaned before bringing your cat into the new environment.