Feline Aggression Towards Other Cats in the Neighbourhood

Key Points

Neuter both male and female cats. Consider time-sharing outdoor access: stagger the times when cats are allowed outside, using electronic cat flaps attached to a timer. Increase resources in the home and garden: indoor and outdoor latrines, more resting places, feeding and drinking sites. Introduce activity feeding. Schedule time for interactive play to coincide with peak periods when cats would otherwise be active outside.

Introduction

Aggression between cats in a neighbourhood will be minimal if they are able to successfully maintain and control territorial boundaries and distance form one another, and thereby avoid face to face confrontations. However, in urban areas the population density of cats may be very high, and cats are forced to traverse each other's territory in order to gain access to the resources that they need. Conflict is more likely if one of the neighbourhood cats is an intact male, as these are far less tolerant of the presence of other males (intact of neutered) and will attempt to attack and drive them away.

Most cats that have outdoor access will, at some time, either be frightened or attacked by a neighbourhood cats, but injuries are usually minor. However, it must be remembered that any level of physical conflict between cats is problematic and unusual for the, as their entire social and communication framework has evolved to prevent this. As a result, we would expect even minor injuries to be associated with a stress related impact on cat welfare. In a recent, unpublished, study by the author, cats that had experienced injuries by other cats were more likely to have significantly higher levels of coat problems, respiratory disease, and eye infections, as well as indoor spray marking problems.

In most cases inter-cat aggression toward neighbourhood cats is only reported when the problem becomes extreme. For example, when a local cat is identified as the culprit for regular home invasions and attacks on other cats. The owners of the cats who fall victim to this behaviour may even pursue litigation, but this is difficult to achieve given legal issues regarding the ownership, and responsibility for, pet cats. Usually the reason for a cat entering the home or territory of another cat is to get food or shelter, and they may seek out homes with cats that are easily intimidated. However, there are instances of male cats travelling considerable distances and engaging in fights with other cats in an area, very much in the same way as an intact male would. The cause of this is unknown, but usually it does not relate to incomplete neutering. Within households some cats show an unusually high level of control over resources, preventing other cats from accessing them. This is sometimes termed despotism, and it is possible that such cats are also those which go on to despots a neighbourhood. Certainly there dis a large amount of individual variation in feline personality, with some being much more bold, confident and assertive.

Prevalence and Risk factors

There is no peer-reviewed published data on the prevalence of inter-cat conflict in neighbourhoods, but the treatment of cat-inflicted bite and scratch injuries are a mainstay of general practice. In one unpublished study, the prevalence of owner-reported cat-infliucted injuries that did not require treatment was 1.09 per cat per year for males, and 0.36 per cat per year for females. The rate of injuries that required veterinary treatment was approximately half this rate for each sex group. The same study found that 16.8% of cats experienced severe problems of being frightened or attacked by neighbourhood cats in the garden, to the extent that it was difficult for them to go outside. Cats were more likely to be severely affected if their owners observed large numbers of cats frequently visiting the garden, indicating that the problem related to local overpopulation and competition for resources. 52% of cat owners in this study indicated that neighbourhood cats had entered their home to steal food and fight with their cats. This indicates that the problem of inter-cat aggression are potentially more severe than reported.

Whilst cat population density is factor in inter-cat aggression in a neighbourhood, studies have shown that cats are able to cope with very high population density if the resources they need are in similarly high density. Competition for resources is a better predictor of conflict, and is something that can be tackled by owners.

Only about 45% of UK cats are meal fed, with the remainder being meal fed or fed on demand. Wild and feral cats eat between 10 and 20 small meals each day, which is far more frequent than any owner would normally offer food. Any form of feeding other than ad-lib can therefore cause cats to experience extended periods of hunger that may force them to increase their foraging activity, and can lead to cats invading the homes of other cats to steal food. This is just one potential underlying motivation for cats to enter territory, and homes, and thereby end up in physical conflict with other cats. The same situation can occur when cats seek shelter, latrine sites, and places to hunt. Owners need to find ways to provide for their own cats' needs, so that they are not forced to seek resources elsewhere.

Investigation

Aggression within a local cat population may be obvious to those who own cats that are the repeated victims of cat bite injuries. Sometimes injuries are mistakenly attributed to foxes or other wildlife, but this is much less common. Inter-cat aggression in the neighbourhood is also an important underlying factor in house-soiling and spraying problems, as well as inter-cat aggression within the household. This is because the activities of local despots, or a very high feline population density may cause cats to stay indoors, where they then conflict with each other.

Aggression to other cats in the neighbourhood is more likely when the local population is destabilised by introduction of a newcomer, when there is one or more entire tomcat in the local population or when a feline despot is resident in the neighbourhood. Despotism is seen when a cat is actively displacing others from their territory or monopolising resources. Conflict is also at a peak when queens are beginning to call and territorial areas are disputed.

Territorial area closely corresponds to the survival resources it provides. The defence of territory is therefore linked to the defence of resources so that there is a reduction in territorial behaviour and aggression when there is a surfeit of resources within the neighbourhood.

Treatment

The majority of domestic cats are neutered and inter-cat aggression within neighbourhoods is consequently reduced but, in situations where two entire males live in close proximity, the risk of overt aggression is greatly increased. In such situations the aggression can be very serious since reproductive, and hence genetic and evolutionary, success is at stake. Neutering before 12 months of age has been shown to decrease fighting by as much as 88%, which suggests that in the case of male to male inter-cat aggression, hormonal influences are perhaps more significant than learning.

Intact male cats that are the cause of aggression should be neutered. If these cats are feral they will need to be trapped and relocated. Some make good pets once they have been castrated. If that intact male belongs to a local resident they must be contacted for permission to have the animal neutered. The surgery may be sponsored by a local charity or shelter organisation if the owner is unable to pay. In a minority of cases, the owner may be unwilling to have the cat neutered.

Aggression between entire males and females is rare, although it may occur if the female is not ready or willing to mate. The mating process is a very noisy event and it is not uncommon for inexperienced owners to misinterpret this as an episode of aggression. When owners report that entire cats of different sexes are acting in a hostile manner toward one another it is therefore important to consider the differential of normal mating behaviour.

Another hormonally-related aggressive behaviour relates to the change in behaviour of lactating queens who can become increasingly aggressive toward other cats when they have a litter to protect. Such aggression may occur within the neighbourhood or inside the household and whilst hostility toward other cats can be considered normal at this point, aggression toward owners in a domestic situation should not be accepted as part of normal “maternal aggression”. Prospective owners should therefore resist the temptation to purchase kittens from a queen that is overtly hostile to them. Cats showing maternal aggression of this kind should be neutered so that further breeding cannot occur. If aggression is directed only at other cats then the owner has a responsibility to house the cat securely to prevent this occurring.

In some cases the general feline population is so large that resource density and individual territorial space are insufficient to prevent aggression. In these cases neighbours may have to make a concerted attempt to improve the local environment so that cats may coexist. The temptation to introduce more cats should be resisted. Timesharing access to the garden may effectively reduce the population density that each cat experiences, but this must be combined with improved resource access and environmental enrichment in the home.

Prognosis

The prognosis is guarded, because in many cases new residents will introduce new cats. Every change or increase in population brings further competition and instability. Successful management of a local overpopulation problem depends upon active participation by all cat owners.

Prevention

• Neuter male and female cats.
• Do not introduce cats that have a history of despotism to already highly-populated neighbourhoods.
• Be aware of local feline population density before introducing more cats to an area.
• Provide places in the garden for resident cats to claw mark, so they can define the territory boundary.
• Provide outdoor latrines (sand pits) at the edge of the garden.
• Increase the cat’s access to height in the garden by creating perches in trees and on walls/fences that look away from the house. This gives cats a chance to defend their own territory whilst preventing other cats from using the perches to spy on the cat’s house.
• Encourage local cat owners to adopt activity feeding and other environmental enrichments that are known to encourage cats to live in harmony.
• Consider persuading cat owners to set up a local ‘cat club’ of people living in the neighbourhood so that they can swap ideas about improving gardens and homes to suit the cats better.