Aggression in Cats (Overview)

PetMD Editorial
By PetMD Editorial
Published: August 14, 2008
Aggression in Cats (Overview)

Cats are small, and often become the target of other animals, making them vulnerable to all kinds of dangers. Anyone who owns a cat understands that it needs protection, especially from dangers that can be encountered outside of the house. This vulnerability accounts for the built-in aggression response cats have when they perceive a threat. Aggression can also come from fear, a health condition, genetic predisposition, an environmental change, or to protect its territory. However, overaggressive behavior can make a cat difficult to live with.

Symptoms and Types

Many aggressive signs are accompanied by a fearful body posture and facial expression, and with submissive behavior. Some cats exhibit these signs if they are cornered, feel like they cannot escape, or are provoked. There are a few types of aggression, including intercat, predatory, territorial and those induced by fear, pain or punishment. Some common signs of these types of fear include:

  • Staring
  • Stalking
  • Hissing
  • Swatting
  • Pouncing
  • Showing teeth
  • Arched back
  • Tail straight up
  • Ears pulled back
  • Dilated pupils
  • Raised hair on the back (hackles up)
  • Attacking with claws and teeth
  • Marking a territory by chin-rubbing or spraying
  • Drawing in the limbs (purpose: hide neck and belly)

Of these types, predatory behavior requires separate treatment because it is so strong in cats. Normal predatory behavior sets in at about five to seven weeks of age. Hunting behavior may be passed from mother to kitten because different skills are used to kill certain kinds of prey. By 14 weeks, a cat may be a very good hunter. Well-fed cats may not be predatory at all, or they may kill and only behead the prey. Stalking and hunting is more common in cats that must fend for themselves.


Stealth, silence, concentration, slinking, lowered head, twitching tail and pounce posture all characterize predatory behavior. The cat will then lunge or spring at the prey, clutching the object of its attack with its claws and teeth. A new male in a group may kill kittens to encourage a female to come into estrus, or heat. At times, a cat may “prey” on things that are not appropriate, such as a foot, a hand, or an infant.


The causes for inappropriate or unwanted aggression can come from many sources. For example, in the same way that some people have serious and grumpy dispositions, cats, can be born with an aggressive personality type, too. Also, if the cat had no human contact before the age of three months, or has not had social interaction with other cats, it simply does not know how to behave appropriately.

Conversely, if the cat shares the home with other cats (or animals), it may be asserting its hierarchy within the social group. This may be especially relevant as the cat reaches the age of social maturity -- around two to four years of age. Age is a significant consideration regarding behavior, since play aggression is an important developmental stage for a kitten. Natural predatory behavior starts around 10 to 12 weeks of age, and will generally wind down on its own if you respond to it correctly.

Fear can also bring on aggression. Cats that are traumatized by unhealthy environments, such as shelters, cages, or overcrowded catteries, occasionally lash out aggressively. This can be particularly true if they have been abused by animals or humans, and especially so with children, since small children tend to be rough with animals. If your cat has developed a fear of children it may become aggressive with all children.

“Normal” acts of aggression can also take place when the cat feels a need to be on the defensive. A mother will naturally be aggressive in protecting her kittens, and likewise, a father cat will do the same. Some cats will stake a certain amount of territory as their own, and will physically assert their dominance of that territory.

If you have exhausted all of the motives that could be causing your cat's inappropriate behavior, and still not found a solution, you will want to take your cat to see your veterinarian, in case there is an underlying medical condition that needs to be treated. Sometimes aggression may indicate that the cat is in pain and does not want to be touched, or that it is suffering from an illness that is affecting its temper.


The diagnosis is generally made from observing dominance behavior, conflict aggression, and social status aggression. However, there are also some medical conditions that can bring on behavioral changes and that might be mistaken for aggression. Your veterinarian will want to rule these out before addressing any behavioral issues:




If your veterinarian identifies an underlying disease responsible for the cat’s behavior, it will be treated first. If there is no underlying illness, it is up to you to re-train your cat. If it is determined that your cat's behavior is driven by experience or lifestyle, behavioral modification techniques will be put in place. Just remember, you are the boss, and the change in attitude that you will need to make on your side, in order to encourage change on your cat's behalf, will be a permanent change, or the cat will slip back into its old behavior.

Some of the modification training will include:

  • Avoiding frightening situations
  • Avoid provoking or instigating aggressive behavior
  • Identifying the situations that will initiate a bad reaction from the cat
  • Learn to read the signs (e.g., tail flicking, ears flat, head hunched, low growl, etc.)
  • Leaving the cat alone when it is aggressive
  • Identifying situations when the cat is calm, so behavior-modification training can be carried out
  • Rewarding good behavior and punishing bad behavior
  • When aggression signs are present, let the cat fall from your lap or walk away from it, and refuse to give it attention until its behavior has changed
  • For aggression between cats, separate them and keep the aggressive one in a less favorable area
  • The use of leashes and harnesses to help in desensitizing and conditioning
  • Clicker training, in which a clicker is used to encourage desired behavior, might also be considered

When training for behavior modification, keep in mind that sessions should be kept short to avoid resentment, boredom and resistance. It is very important not to use physical punishment of any kind; it will only exacerbate the problem.

If you and your veterinarian conclude that your cat's predetermined personality is at the root of the behavior, and it cannot be modified extensively, you may want to consider one of the mood-enhancing drugs on the market that are specifically formulated for pets. The availability of drugs is limited for cats, and as with any drug, if you do decide to use them, be alert to possible unfavorable side effects. Otherwise, accommodating your cat's personality, as you would for a family member, may be your best option. You will want to keep your cat safe from fearful situations, and safeguard other animals, and people, from your cat's tendencies to act out.

Image via Shutterstock

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