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Cat Aggression: Why Some Cats Fight

Aggressive cat hissing at a new cat.

While cats are sometimes solitary hunters, they often prefer to be in the company of other cats as well as their humans. Many cats crave a cuddle buddy, playmate, and the overall company of another living creature.

There are many cats, however, that would prefer to be alone. Usually, these cats were not properly socialized as kittens or have had bad experiences early in their lives. This can make them difficult when confronted with other felines in the home.

Will Your Cat Accept Other Cats?

If your cat displays the following behaviors, don't bring home any other cats:

  • Skittishness around strangers.
  • Negative reaction when viewing other cats through windows.
  • Fighting with other cats.
  • Indoor behavior problems such as marking, not using the litter box, or displaying aggression toward other resident pets.

While some cats might eventually come out of their solitary shells after living with another cat, it can certainly be a long process, requiring a lot of effort from you. Solitary cats that adore their humans can become friendly when they see you giving attention to another cat. Then again, some cats can also become aggressive in that situation if they view you as a resource instead of just a companion.

Reasons for Feline Aggression

As with all pets, neutering or spaying is the first step in creating a harmonious household. If you have an aggressive cat, this is the first thing you need to do. A neutered cat is less likely to feel as though his territory is threatened, though all cats are highly territorial.

Secondly, cats immediately dislike other cats that do not smell the same as they do. Sometimes, there can be a short-lived dislike between cats if one spent time at the veterinarian's office or elsewhere and returned home with a different odor.

A cat colony consists of felines who live in the same area. While each cat has his own scent, they also carry the scent of their living area. So a group of cats in your home have the scent of your home all over them. Leaving for even a short period of time can create a change in odor, causing a brief rift between formerly peaceful housemates.

How to Equalize Your Cats' Scents and Introduce or Reintroduce Them

  1. Bathe each cat or give a thorough wipe-down with a dry shampoo product.
  2. Take a cloth and rub each cat's anal area, then rub this cloth around each feline's neck and back. This places the same scents on all of the cats.
  3. Prior to allowing the new or returning cat free roam of the house, place a heavy scent on all of the cats' foreheads, such as a few drops of vanilla food flavoring. Placing Feliway cat appeasing pheromone diffusers throughout the house can also be helpful.
  4. For cats that are completely new to each other: Allow the cats to first sniff each other through a closed door. Place some food, such as cooked chicken or tuna, near the cats so that they can acquire positive associations with the scent of each other.
  5. If there is no negative reaction (yowling, hissing, spitting), allow them to interact at a distance. Keeping them tethered with a leash or a body harness will help you control the situation more effectively. Gradually decrease the distance as each cat learns to ignore or accept the presence of the other cat.
  6. Create a positive association with their interactions by playing with the cats and offering food rewards as they remain relaxed.

When you are not able to observe your cats, keep them separated until you are sure they get along. Controlling their interactions will help ensure that they have positive experiences, which in turn aids in the forming of an amicable relationship.

Feline Aggression Occurs in Different Forms

Many mother cats will suddenly display aggression to other household cats. This is a natural maternal protective instinct. When the kittens are weaned or leave the premises, your cat will eventually return to being friendly with her housemates.

Some cats display displaced or redirected aggression. While she may normally be friendly with other household cats, your cat might suddenly become aggressive if she sees something outside the window or if there's a change in the household. Her aggression is displaced onto the closest feline, human, or dog within reach as she experiences the threat.

Usually a Feliway diffuser is helpful in this situation. It might also be helpful to have an object near the window that will allow you're freaked-out feline to rid herself of her aggression. A scratching post, pillow, or large stuffed toy might work.

You can read more about the types of feline aggression here.

NOTE: There are some cats that will never accept the presence of other cats but might be more amenable with a dog or other pet. Do not force the issue by getting another cat anyway. This can cause territorial marking, destructive clawing and chewing, dangerous fighting and displaced aggression toward you, destroying your relationship with your kitty.

You may also like the following articles:

How to Introduce a New Cat to a Household that Already Has a Cat

Cat Aggression Overview

Territorial Aggression in Cats

Injury or Illness-Related Aggression in Cats

Redirected Aggression in Cats

Play Aggression in Cats

Human-directed Aggression in Cats

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