Integration and Aggression Between Cats

Many factors determine how well cats will get along with one another, but even animal behavior experts don’t fully understand them.

Your cat’s best friend may not be another cat. Cats are very territorial creatures and often vehemently defend their turf.

Because of this, it’s not uncommon for the addition of a new cat to your household to create some inter-cat strife.

Adding a second cat

Many people adopt a second cat thinking that the resident cat will be happy. This is a risky move. Just because your cat is sweet and loving with you doesn’t mean he’s going to be sweet to another cat.

Although you can increase the chances that they will get along or at least tolerate one another by making proper introductions, there’s no way to predict whether cats will get along with each other. Unfortunately, there’s no training method that can guarantee that they ever will. But we’re here to help negotiate a truce.

Types of aggressive behaviors

First, let’s understand the different types of aggression and what causes them.

Territorial aggression

This occurs when a cat feels that an intruder has invaded her territory.

A cat may be aggressive toward one cat (usually the most passive), yet friendly and tolerant with another.
Problems often occur when a new cat is brought home, a young kitten reaches maturity, or a cat sees or encounters neighborhood cats outside.
Typical behavior includes stalking, chasing, ambushing, hissing, loud meowing, swatting, and preventing access to places (such as the litter box, bedroom, etc.)
Female cats can be just as territorial as males.

Inter-male aggression

Adult male cats may threaten, and sometimes fight with, other males. This is more common among unneutered cats. They may fight over a female, for a higher place in the pecking order, or to defend territory.

Cats stalk, stare, yowl, howl, and puff up their fur (picture the arched back of the Halloween cat) to threaten each other. If one does back down and walk away, the aggressor, having made his point, will usually walk away as well.

If no one backs down, cats may actually fight. They may roll around biting, kicking, swatting, and screaming, suddenly stop, resume posturing, fight again, or walk away. If you see signs that a fight may occur, distract the cats by clapping loudly, tossing a pillow nearby, or squirting them with water. These actions can also be used to break up a fight. Keep your distance, and never put body parts in the middle of a fight; you could be injured.

Defensive aggression

Defensive aggression occurs when a cat tries to protect himself from an animal or human attacker he believes he can’t escape. This can occur in response to the following:

Punishment or the threat of punishment from a person
An attack or attempted attack from another cat
Any incident that makes the animal feel threatened or afraid

Defensive postures

Crouching with the legs and tail pulled in under the body
Flattening the ears against the head
Rolling slightly to the side

Approaching a cat in this posture is likely to cause an attack.

Redirected aggression

Cats direct this type of aggression toward another animal, or even a person, who didn’t initially provoke the behavior.For example, your cat is sitting in the window and sees an outdoor cat walk across the front yard. He gets very agitated because that cat is in his territory. You pet him; he turns and bites you. He doesn’t even know who you are at that point—he’s so worked up about the cat outside that he attacks the first thing that crosses his path.

Consult with a veterinarian

Your first step should always be to contact your veterinarian for a thorough health examination. Cats often hide symptoms of illness until they’re seriously ill; your aggressive cat may be feeling sick and taking out his misery on others.

If your cat gets a clean bill of health, consult your vet or an animal behavior specialist for help. A behaviorist will advise you on what can be done. You may need to start the introduction process all over again, keep the cats in separate areas of your home, or even find one of the cats a new home if the aggression is extreme and can’t be resolved.

Consult with your veterinarian about a short course of anti-anxiety medication for your cats while you’re working on changing their behavior/s. Never medicate your cat on your own.

Prevent future fights

This could mean keeping the cats separated from each other while you work on the problem, or at least preventing contact between them during situations likely to trigger a fight.

Spay or neuter your pets. The behavior of one intact animal can negatively affect all of your pets.

What to avoid

Don’t count on the cats to “work things out.” The more they fight, the worse the problem is likely to become. To stop a fight in progress, make a loud noise (like blowing a whistle), squirt the cats with water, or throw something soft at them.
Don’t touch them, or you might get seriously scratched or bitten. Seek medical attention if you’re injured.
Don’t punish the cats involved. Punishment could cause further aggression and fearful responses, which will only make the problem worse. You could even become a target for redirected aggression.
Don’t add more cats. Some cats are willing to share their house and territory with multiple cats, but the more cats who share the same territory, the more likely it is that some of your cats will not get along with each other.

Cat friendship is a feline mystery