Cat Tail Signals
A cat's tail acts as an extension of its thoughts, an indicator of its mood and a warning of intention.
Broad swishing of the tail indicates annoyance. For example, a cat who decides she's had enough petting will swish its tail in impatience. If you continue, your cat may "bat" you with her paw or growl softly. Though usually good-humored, the batting is an act of aggression indicating your cat's agitation.
Severely agitated cats move their tails rapidly back and forth from the base, a clear threatening signal. Generally, the larger and more rapid the swish, the more upset the cat. Exhibiting a visible warning to other cats (and to you) is her way of avoiding direct conflict. Cats involved in a conflict may extend their fully bristled tail straight into the air and turn their body sideways to appear larger.
With prey, though, the tails of hunting cats show more subtle movements, explaining to other cats their intention while not warning their victims.
When a cat is afraid or is trying to avoid a confrontation with a dominant cat, his tail will "puff up" or become bristled. He will then lower his tail or tuck it betweens his legs as a sign of submission.
Unlike switches, twitches of the tail display excitement and curiosity. A raised tail - as long as the fur isn't bristled - indicates that the cat is being friendly. If the cat is excited, as when you come home after a long day at work or when you open a can of cat food, the upraised tail might twitch in anticipation. The cat will probably vocalize or rub against her owner.
When the tail is erect for its full length, it is used as a greeting to another cat or to a friendly human and is an invitation for contact rubbing. This can also be a request for food. The tail flicks of a seated cat often indicates irritation. Tail wagging can range from small irritated flicks which may express indecision--wavering between two possible courses of action--or in its most pronounced form, it can be the prelude to a fight between two male cats and undoubtedly accompanied by growling.
A tail that is held down with an elevated rump belongs to an aggressive cat that is standing sideways near another cat. A fluffed-up, arched tail is seen when a cat stands with its back arched (the "Halloween cat") and it is torn between being aggressive or defensive. A fluffed tail that is positioned straight out or down, is seen when the decision moves toward aggression. (All of these tail positions can be observed when two kittens engage in play fighting.) The tail that is wrapped against the cat's body may mean that the cat is contented or for a nervous cat, it is a defensive posture.
Each movement of a cat's tail communicates its emotional state. The tail wagging of a cat in conflict is perhaps the most familiar, but there are other tail signals that humans might learn for a clue about kitty's mood at the moment:
Tail is curved gently downward and then curves up again at the tip.
The cat is relaxed and at peace with the world.
Tail is raised slightly and softly curved.
The cat is beginning to get interested in something.
Tail is held erect, but tip is tilted over.
The cat is very interested and is in a friendly mood, but has slight reservations.
Tail is fully erect, and tip is stiffly vertical.
The cat is offering an intense greeting without reservations.
Tail is erect with whole length quivering gently.
The cat is displaying affection, as in response to a greeting by a favored human.
Tail is held still, but tip is twitching slightly.
The cat is mildly irritated.
Tail is held still, but tip is twitching vigorously.
The cat is very irritated, and a bad-tempered paw swipe is about to occur.
Tail is swishing vigorously from side to side.
The cat is angry and about to attack.
Tail is held straight and fully bristled.
The cat is aggressive.
Tail is arched and bristled.
The cat is defensive and may attack if provoked further.
Tail is lowered and fluffed out.
The cat is indicating an active fear.
Tail is fully lowered and may be tucked between hind legs.
The cat is giving a signal of defeat or total submissiveness.
Tail is held to one side.
The female cat in heat is inviting a sexual encounter.