Feline Behaviorist Pam Johnson-Bennett is the author of a number of award-winning and critically acclaimed books, including Think Like a Cat and Psycho Kitty. The innovative methods described in all her books are based on Pam's unique way of training by actually understanding the way a cat thinks. She makes numerous television appearances including CNN, Fox News Channel, and National Geographic specials, as well as being a popular guest on many nationally syndicated radio programs. She is now considered to be one of the leading experts on feline behavior.

Q: I have a five-year-old neutered male housecat, and for as long as I've had him, I've noticed that when he gets excited (before feedings, while playing, if he sees his treats, etc), his tail will stick straight up and move back and forth very fast. It almost looks as though it's vibrating. I had assumed this was something to do with his being a male, or maybe something to do with a spraying tendency. He has never sprayed though. Anyway, my aunt recently adopted a six-month-old female kitten from the pound. This kitten hasn't been spayed yet, and we have noticed that she will often walk around the house with her tail straight up and moving it back and forth very fast. So I was just wondering what this means?

A: This is normal behavior for both males and females, whether they are altered or not. It's connected to spraying only in the sense that it's one of the behaviors a cat exhibits right before actually spray-marking. A cat's tail will quiver when he is excited and in great anticipation of something truly desirable, such as a meal or a treat or affection from you. A cat may also quiver her tail when she's excited but unsure of a situation, such as the case with your new female kitty.

Displacement behavior (doing something to relieve the tension of something else) is very important to a cat in order to control the build-up of anxiety, excitement or frustration. It's not unusual for a kitty to need to do a little tail quivering, grooming, or scratching on the scratching post to release some of that feline energy.

The cat's tail is truly a remarkable tool when it comes to feline communication, isn't it?