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 or 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 cat, but injuries are usually minor. However, it must be remembered that any level of physical conflict between cats is problematic and unusual for them, 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 In a recent, unpublished, study by the author, cats that had experienced injuries by other cats were more likely to have significantly higher levels of coat problems, respiratory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 neutered 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 be despots in a neighbourhood. Certainly there is a large amount of individual variation in feline personality, with some individuals 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-inflicted 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 problems 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 fed ad-lib, 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.

Hybrid Cats

There is a growing trend for people to hybridise the domestic cat with small wild felid species such as the Asian Leopard cat, Margay and Serval. These species are larger and have striking markings. Although they often come from areas of human habitation, and despite thousands of years of contact with people they have not undergone a similar process of domestication as seen in the domestic cat. There is anecdotal evidence that some hybrids, such as the Bengal (a hybrid of the domestic cat and the Asian leopard cat), are more aggressive toward neighbourhood cats and may even kill them. Some hybrids, such as the Savannah, can reach a weight in excess of 15kg, making them potentially very dangerous.

Investigation

Aggression within a local cat population may be obvious to those whose cats are the victims of repeated cat bite injuries. Sometimes injuries are mistakenly attributed to foxes or other wildlife, as cat owners may be unaware, or unwilling to believe, that cats frequently injure each other. 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 despotic cats, or a very high feline population density, may cause cats to stay indoors, where they then have conflicts with each other.

Treatment of neighbourhood cat problems may require the cooperation of several owners in order to improve the local environment for all cats, and thereby reduce conflict. Apart from individual information about the origin, health, and physical and social environment of each cat, it is important look at the physical environment of cats in a neighbourhood to see whether there are specific reasons for certain cats to travel away from their territory and become a nuisance to others.

Treatment

Specific recommendations will differ between cases, but could include:

• Neuter cats. This includes trapping and neutering any stray cats, to reduce population density.
• Ensuring that each household provides its own cat with sufficient resources to limit the need for resident cats to wander. This should include free access to food, water and a choice of resting places. The garden should also be enriched to provide places to perch and shelter, latrine sites and planted borders that enable the cat to hide and which encourage wildlife.
• Installing posts and fences that provide claw marking opportunities for resident cats, to help deter others from entering the garden.
• Use of deterrents to prevent non-resident cats from taking up vantage points, such as sheds and fences, from which they can overlook and territorialise a resident cat's garden (for example, burglar deterrent plastic prickle strips that will not harm the cat but which are uncomfortable to walk or sit on).
• Coded electronic cat door to prevent non-resident cats form entering the home.
• Time sharing may be employed, to allow cats to have outdoor access at different times of day so that they do not encounter each other (this can be achieved using some cat flaps with timer facilities).
• In some cases, cats that seek out and attack other cats may need to be confined or rehomed.

Drug Therapies

In some cases despotic cats may respond well to psychoactive medication such as fluoxetine. If the victims of interact aggression are timid, and unable to territorialise their own garden, psychoactive medication may be used to reduce anxiety. For example, fluoxetine, clomipramine or buspirone.

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.