The answer to this question is “yes” they do. I’ll give you an example. I own a mobile home in Delaware, where I spend many weekends. I’ve spoken to my neighbors and they tell me that mobile homes frequently have mice because it’s easy for them to get in through the heating and air conditioning ducts which run under the floor. I always bring my two cats with me when I go down there. I have never had any mice.  Even if your cat is not a “mouser” his scent should keep away mice.

Over time, mice and rats have evolved a strong aversion to the smell of cats as well as other predators.  Even laboratory raised rodents will freak out when they smell a cat.  There was a study that was done by Japanese researchers that raised a group of mutant mice. These mice could smell cats just fine, they just didn’t know that they should be afraid of them.  When confronted by a cat they chose to investigate and even try to play with it rather than flee!

Don’t worry, your cat will keep mice away. If you don’t have any mice, get him some cat toy mice to play with!