Cat Aggression
Animals of many species strive to expel or keep out other individuals from their territory, and cats are no exception. Both male and female cats are territorial, but males may defend larger territories than females.
Cat territorial aggression is usually directly toward other cats, but it can be directed toward dogs and people, too. A cat can show territorial aggression toward some family members as well as other cats in the household.
Cats mark their turf by patrolling, chin rubbing and urine spraying. They may stalk, chase and ambush a targeted intruder while displaying offensive body postures, hissing, swatting and growling. Some cats take a slow and steady approach in their stalking, while others immediately and aggressively give chase. A cat’s perceived territory could be the entire house or part of it, the yard, the block or the neighborhood.
~ Some of the most common situations that trigger territoriality are:
• A kitten in the household reaches sexual maturity
• A new cat is introduced into the family and household
• Major changes are made in the cat’s family or environment (for example, moving or someone moving in)
• Stray or roaming cats in the neighborhood enter a cat’s territory
~ P l a y ~
Rough play is common and natural among kittens and young cats less than two years of age. Despite the playful intentions of a cat, however, when such play is directed toward people or becomes overly rambunctious, it can cause injury to people or damage household items.
Play aggression is the most common type of aggressive behavior that cats direct toward their owners. It involves typical predatory and play behaviors, including stalking, chasing, attacking, running, ambushing, pouncing, leaping, batting, swatting, grasping, fighting and biting.
It’s believed that through play with each other, young cats learn to inhibit their bites and sheathe their claws when swatting. The degree to which individual cats learn to inhibit their rough play varies, and those who were orphaned or weaned early might never have learned to temper their play behavior.
Other factors that can contribute to play aggression are long hours spent alone without opportunities to play, and if pet parents encourage their cats to chase and attack people’s hands and feet in play.
~ R E D I R E C T E D ~
Redirected aggression is probably the most dangerous type of cat aggression because the bites are uninhibited and the attacks can be frightening and damaging. Unfortunately, it’s also a very common type of feline aggression. 
Redirected aggression occurs when a cat is aggressively aroused and agitated by an animal or person he can’t get at (because there’s a window between them, for example). Unable to get to the trigger of his agitation, he turns and lashes out at someone—person, dog or cat—who is nearby or who approaches him.
There can be considerable delay between the initial arousal and the redirected aggression, as long as hours. This is why cat parents sometimes describe this kind of aggression as unprovoked or “out of the blue.” They weren’t even aware of the initial trigger (for example, a cat outside who passed by 30 minutes before the attack). A redirected attack occurs only if an agitated cat is approached or there’s someone close by.
The cat won’t go looking for someone to attack! It’s not a malicious or even intentional type of aggression. It’s almost like a reflex, done automatically without thought. This is why it’s never a good idea to break up a cat fight or approach an agitated cat showing defensive or offensive aggression postures.
Some common triggers for redirected aggression are:
• Watching another cat through a door or window
• Watching or stalking birds, squirrels or other prey animals
• Smelling another cat’s odor on a family member, a visitor or clothing
• Coming indoors after getting outside if the cat usually lives only indoors
• Hearing high-pitched noises
• Being frightened or harassed by a dog
• Having a person intervene in a cat fight
• Being in an animal shelter, surrounded by the sight, smell and sounds of other cats