Cats are a territorial species, and have evolved a complex communication system consisting of scent cues, vocal signals, facial cues, body language and posture. Aggression between cats can be a perfectly natural and normal behaviour. Although due to their reliance on good health to hunt for food, most cats will attempt to de-escalate conflict before physical aggression is reached. The causes of inter-cat aggression vary, but often involve disputes over territory or shared resources. Fighting between cats can be difficult to manage. And looking into the cause of any dispute is helpful to resolve underlying tensions and restore harmony.

Recognising the difference between play-fighting and true aggression

Cat play usually mimics predatory behaviours, and therefore involves pouncing, chasing and batting at each other with their paws. This can make it difficult to determine if your cats are playing or actually fighting!

Generally, play-fighting is silent, with periods of play interspersed with rest. Any biting is gentle, and claws are retracted. If the play becomes too rough, this may lead to hissing or screeching, which should end the play. After play sessions, the cats will be relaxed and comfortable and interact normally with each other, their owners and other pets. 

Aggression in multi-cat households: what to do

Cats’ social structure can be confusing and complex, especially when you add their territorial natures into the mix! Cats can co-exist in a household without being particularly bonded, as long as they have their separate ‘zones’, enough resources and a degree of compatibility.

If you are experiencing aggression between feline members of your household, it is worth noting that there is no quick fix. Multiple interventions may be required over the course of time, with modifications to your home and interactions with your cats. A clinical animal behaviourist may be required for professional help.

Identify the problem

It is fairly common to have a ‘bully’ cat in the household. These can be identified as they will block access to cat-flaps, food bowls or beds, pounce on a victim cat when they are sleeping, or physically push them away from a key resource. These cats can be difficult to deal with, as it is a delicate balance to make sure the needs of all cats are provided for. Ensuring the other cats have access to safe spaces, hiding places and all their key needs is essential to reduce stress. 

Provide resources

General advice for inter-cat aggression in a household involves ensuring adequate resources for each cat, in different areas. This is because most cases of aggression are due to competition for resources, or when a cat’s key needs are placed in the territory of another cat, leading to conflict. 

A good rule to follow is that all of a cat’s basic requirements (food, water, beds and hiding places, litter trays and toys) should be adequately provided for every cat in the house, plus one extra. For example, if you have three cats, you need four litter trays, four food bowls etc. These supplies should also be spread around the house, so that all cats have safe access to what they need. If you are limited in space, bear in mind that two bonded cats (identified by grooming each other, playing and sleeping together) can usually share resources if needed. 

Food rations should be split into multiple portions and placed in different areas, as with water bowls. Ideally, bowls should be placed not against a wall, so that cats don’t have to turn their backs on the room to eat or drink. Litter trays should be placed somewhere quiet and private, even if the cats have access outside. Conversely, scratching posts should be placed in busy thoroughfares and key entrance/exit ways, as cats communicate territorial messages using pheromones released from their paws when scratching. 

Consider pheromones

Pheromone diffusers may have some role to play in reducing conflict. Cats use pheromones to communicate messages both to themselves and other cats. Using these scent chemicals to promote harmony can help restore calm, but are most effective when used alongside environmental modification. 

Start over

If an instance of acute aggression occurs – for example, one cat is attacked when it returns from a trip to the vet, separate the two cats for 24-48 hours and then re-introduce slowly. Scent-swapping using bedding or toys can be useful if one cat has been away from the home and is struggling to re-integrate. 

Seek help

If you’re experiencing aggression between your cats, this can be stressful, distressing and hard to manage. A good first port of call is your vet. They will be able to check over your cats for any medical issues which may be contributing, such as chronic pain, and discuss the problem. They may well be able to refer you on to a trained, registered behaviourist if needed. If you want to find a professional behaviourist, a good place to start is the Animal Behaviour and Training Council

Aggression outside the home

Due to their territorial natures, aggression is fairly common between cats with a shared geographic or physical boundary. Cats have a high threshold for physical aggression, and conflict is often reserved to tense postures and body language, bushy tails, hissing and growling. However, some cats are aggressively acquisitive of new turf, and can make themselves a nuisance in the garden or even home of another cat. 

Resolving these external conflicts can require some cooperation between the owners of feuding cats. It can be helpful to restrict outdoor access if one cat is determinedly aggressive. Or to agree a schedule where only one of the cats is out at a time. Boarding up known garden access points, securing cat flaps and windows and considering deterrents can all be useful. If a cat is actively invading the home, a microchip cat-flap is a very useful purchase to avoid this stressful event. 

Help! My cats been fighting!

If you are aware that your cat has been in a fight, confine them to a room if possible and allow them to calm down before you attempt handling. Check them over for injuries and any pain. Scratches are often superficial and quickly healed, but bite wounds can be deep and lead to infection. The puncture wounds can also be difficult to see as they are small and often covered in hair. Monitor your cat closely for signs of lethargy, limping, pain (this may be seen as a negative response when stroked on handled) or a poor appetite, and take them to a vet if you are concerned. 

Cat fights: summing up

Cats tend to avoid physical aggression where possible, but occasionally conflict is unavoidable. Fights between cats in the same household can occur due to unintentional restriction or poor positioning of resources. Providing key feline needs in multiple areas and in good amounts can go a long way to resolving conflicts. Provide safe spaces for more timid cats, and try to restrain more assertive feline members from taking over the household. External conflict can be very stressful to cats. Try and make your home and garden as safe as possible for your cats by blocking access from intruders. 

Behavioural problems can be difficult to manage. If you’re concerned about your cats, always speak to a vet or qualified behaviourist

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