Hissing, biting, pouncing, growling… aggression in cats can be difficult to witness, and to manage. Aggression is not a character trait, but an expression of behaviour in challenging circumstances – for instance, when your cat is scared or defensive. Learning how to read your cat’s behaviour and body language, and how to deal with aggressive behaviours, can be invaluable for many cat owners. 

Table of contents

Are cats naturally aggressive?

Actually, quite the opposite! Cats are solitary hunters, and therefore independent and self-reliant, and so physical fighting is ecologically speaking a bad idea. Any fight leading to injury could affect their ability to hunt, and therefore to survive. They therefore have a complex and sophisticated communication system made up of scent marking, body language and vocal cues to try and diffuse any potential conflict. 

However, some confrontations are unavoidable if the cat feels that aggression is the only remaining option. Some cats will be quicker to move to attack than others, depending on their personality. Read more about cat personality types that may predispose to aggressive behaviours here. 

1) Cat-on-cat aggression

Aggression between cats is the most common type of feline conflict. There are various reasons why cats might fight. 

Firstly, cats are territorial, with their territory divided into a ‘core’ area, which consists of the places most significant to them, and a ‘peripheral’ area in which they may patrol and hunt. Cats will defend their territory – some will focus on their small core territory, others will actively seek out extensions to their peripheral haunts. These battles for territory can occur both between cats within the same household, or cats from different households.

Cats within a household can also fight over resources, including where food is located, premium resting spots and for good entry and exit points to the house. Even the smallest house can become divided into a complicated mash of safe zones for its occupants. 

Aggression can also occur between breeding females, usually when a mother cat is defending her kittens. 

Recognise aggression between cats in a household

It can be difficult to tell the difference between playfighting and true aggression. Playfighting is usually silent, with bursts of activity (chasing, rolling around, batting with paws) interspersed with periods of rest. Both cats keep their claws retracted and any biting causes no injury. Playfighting can occasionally get too rough and noisy, but tension always diffuses quickly after any episode. 

True aggression involves much more build-up: hunched body language, ruffled fur, hissing, spitting and often very loud vocalisations. Bites can be severe, and injuries are common. 

In households with more than one cat, if there is conflict, it can range from the obvious to the subtle. There is often one ‘bully’ cat, who can exhibit rude behaviours such as physically evicting another cat from a bed or your lap, unprovoked pouncing or other aggressive behaviours. Subtle bullying can be harder to spot as it often involves sitting casually somewhere by a cat flap, food bowl or litter tray to block access. 

Reduce aggression between cats in a household

There is no simple answer to that question, and it may be wise to seek advice from a veterinary surgeon or veterinary behaviourist to discuss any specific problems. Here are some general tips to try for general inter-cat aggression. 

  • Provide plenty of resources (food bowls, water bowls, litter trays, beds), preferably more than the number of cats you have, and situate them in multiple areas of your house so that all cats have access
  • Plenty of litter trays should be provided, even if the cats have access outdoors, as this may be being limited
  • Provide plenty of ‘feeding stations’ with dry food given in multiple small meals – this makes cats more relaxed about the availability of food, and allows them to choose the safest time to eat
  • Cats love high places, provide plenty of appropriate resting places and hiding places to act as safe zones.
  • Scratching posts placed near beds, feeding areas and entrances can help make territories more decisive and reduce quarrels

Reduce aggression from a cat from outside your home

It can be distressing to have your cat apparently targeted by another cat, especially if they are becoming distressed or injured. This can be difficult to manage, as often the bullying cat may be unknown.

  • If you know which cat is causing problems, and an owner can be located, a polite conversation may be useful. A mutual agreement that the more aggressive cat could be kept indoors at problematic times (usually overnight) may be possible.
  • Minimising the aggressor’s access to your property can both reduce contact and reassure your cat. Block the cat’s route into your garden, seal the cat flap and keep doors and windows closed. A microchip cat flap can be ideal to allow your cat access without any intruders. 

2) Cat on human aggression

Aggression is not a type of character, it is a consequence of various behavioural states, and so each case is very variable. Again, expert behavioural advice might well be needed. 

A cat being aggressive towards a human, usually an owner or visitor, is normally due to one of a few causes. Physical causes, such as pain or illness, should always be ruled out by a veterinary surgeon first. Cats are very good at hiding pain, and unprovoked aggressive responses to stroking and normal interaction can be a tell-tale sign that something is wrong. 

Once any physical problem is ruled out, this leaves behavioural causes: inappropriate play, frustration, fear or anxiety. 

Warning signs

Cats can be quite subtle with their body language, and learning to read their cues can be really helpful to prevent aggression. Early signs of aggression include:

  • Staring, especially if the pupils are dilated
  • Tail twitching
  • Flattened ears, or ears rotated back
  • Crouched or rigid body position
  • Hissing and growling. 

If you notice these signs, back away and give your cat some space. 

Common problems

Cat aggression is a very individual issue, and trained behavioural advice is best if you are struggling to deal with your pet, but there are some common scenarios that may be helpful.

1. Kitten biting 

Kittens play to learn how to hunt, and can get rough and excitable. Playing with your kitten using your hands and feet is a really bad idea, as the kitten learns that biting, pouncing and scratching is acceptable. Always use toys for playing, and hands for stroking, holding and feeding. Do not punish your kitten if they play roughly, but redirect towards a toy. 

2. Attacking when they see another cat outside 

Cats can become anxious when they see another cat, and when the owner tries to reassure them, they can become the attention of re-directed aggression. This can escalate if repeated enough into the cat associating the owner with fear, so needs to be avoided. 

3. Aggression when being petted 

This can often be seen as unprovoked and can be very upsetting. Most cats will have a ‘threshold’ of how much stroking they enjoy, which can quickly turn to being unwanted. Most cats will give off signals that they have stopped enjoying being stroked, such as a twitching tail or flattened back ears, so learning to read your cat’s signals is essential. 

Aggression is never pleasant to witness – especially if we are on the receiving end! It can become very distressing to be around a cat who uses aggression to escape situations they are uncomfortable in. Learning to read your cat’s signals can be a really useful first step to understanding their aggression, but seeking advice from a veterinary behaviourist may well be needed to fully resolve issues. 

You might also be interested in: