Distinguishing the many instinctual feline behaviors that have past on from generation to generation of cats is like a top hat filled with raffle tickets. Reach in and you will have a variety to choose from. Considering the length of domestication, cats are an animal that still clearly contain innate behaviors, and can often surprise a novice cat owner. It is not unlikely for a new cat owner to become startled, if not curious, once witnessing his usually friendly cat pull a Jekyll and Hyde, hissing aggressively.
The hiss of a cat very closely resembles that of a snake in both vocalization and physicality. This is called mimicry and is not uncommon in the animal kingdom. Assuming the position of something frightening and dangerous, the cat's hiss should most often be acknowledged as a natural act of defense. There seem to be a number of reasons that cause this type of behavior.
Apparently, male un-neutered cats are more prone to become the hissing culprit. They carry and are affected by more hormones than others. They are also the most likely to scrap with other cats, which will lead to hissing before, during, and even after a fight has taken place. This type of scenario also applies to potential fights that have not actually happened due to one domineering cat scaring off the other. Neutering your cat not only helps reduce many health risks, it will also reduce the urge to fight.
The introduction of a new kitten, cat or even adult can often trigger a hissing fit. Since cats are very territorial, this behavior is one way to caution the unwanted newcomer to learn his boundaries, or to back off. Usually the hissing will not escalate into actual harm, and should be observed but otherwise left alone. This is a natural behavior. An addition to the household usually takes a few days or weeks of learning to adjust, but establishing a line of dominance, so to speak, is common in any animal household. In the case of a human visitor, ignore the hissing cat as best as possible, refraining from punishing the behavior or provoking it. A gradual introduction to both feline and human is a wise move to help reduce the caution displayed by your now riled pet.
Since cats have very sensitive skin, your usually friendly fur ball may spontaneously hiss while you are petting her. This is an attempt to communicate to you that you have overstepped your time petting and your hand has now become annoying or even uncomfortable. If this becomes a pattern, start paying attention to the circumstances just before the hissing began, i.e. how long were you petting your cat, were you petting repetitively in just one spot, or did you begin thinking of something that would have caused your emotions to shift? Observing the catalyst of this type of communication can possibly help prevent it in the future.
It is also pertinent to rule out any medical conditions that may cause a drastic change in your cat's behavior. Many illnesses will cause an underlying mood change that will come across as irritability, aggression, discomfort, etc. Considering cats can t speak in words that humans can understand, they will use many vocalizations to get the message across.
Once determining the most likely onset of such behavior, it is much easier to reduce or even stop the hissing all together. It is important throughout the entire process, however, not to punish or confront the cat, which may further push him into a dyer sense of defense. Rather, observe the behavior, search for clues as to why your cat is displaying this type of aggression and begin seeking behavioral modifications that pertain specifically to the cause, if necessary. Many instances of hissing simply go away on their own, while others may need a little redirection or encouraged change. All in all, just like their human companions, cats are animals and it is completely natural for them to display a vast spectrum of expression. It is common knowledge that when communicating, humans don t like to be muted, nor do they appreciate being punished for expressing extreme emotions. Consider this when enduring the next hissing fit your feline feels like releasing.