Although some owners appreciate their dog's warning barks and guarding behavior, territorial aggression can be embarrassing for an owner and potentially dangerous to human and/or canine visitors to the property. When dogs show excessive aggression to other dogs on their home turf but do not respond aggressively to unfamiliar dogs on neutral territory, territorial aggression is the likely diagnosis. There are two different motivations for territorial behavior: dominance or fear/anxiety.Territorial Dominance Aggression
True territorial aggression is like dominance aggression, except on a larger scale. While dominance aggression expresses itself between individuals pack members, and serves a "cohesive" function in the pack, territorial aggression is outwardly directed and its function is "dispersive." With territorial aggression, the resources guarded are those within certain physical boundaries – the territory – and the objects of the aggression are unwelcome visitors to that territory. The shelter and food that the territory provides and the incumbent society, the pack, must be defended against infiltrators and usurpers. In the wild, responsibility for this function rests squarely with more dominant members of the pack. It is their duty to alert the others and repel interlopers, as the need arises.
Similar behavior occurs in domestic dogs of a dominant disposition, though the circumstances are somewhat different. First of all, the pack comprises members of their human family as well as other dogs. Secondly, the territory that they protect includes the house and yard plus areas like sidewalks that the dogs regularly patrol and vehicles in which they ride. Finally, these dogs do not just defend the territory against canine invaders: They also guard against unwelcome human visitors. See Territorial Aggression toward People
As one Border collie herding trainer once said, "Dogs are territorial animals. If you allow them to live in your home but fail to make it absolutely clear that you are the leader, they will take over the territory, protecting it against all comers, and will condescend to let you live there because you supply their food." Although an extreme view, it makes the point. Dogs that are overly dominant, both in absolute terms or with respect to their human family members, can provide a serious obstacle for canine and human visitors to their territory.
Treatment for dominance-related territorial aggression toward other dogs is best accomplished through strong leadership on the part of the owner (e.g. the owner should engage a leadership program) and they should employ effective physical methods of control. Territorial/Fear Aggression
Not all dogs that display apparent territorial aggression toward other dogs have a dominant disposition; at least, dominance may not be the driving force behind their aggressive displays. Instead, the dogs may be anxious by nature or have been undersocialized and poorly trained as youngsters. Their aggression is designed to isolate them from another dog's approach. Although they may not be particularly comfortable around other dogs when away from their territory, once home they have enough confidence to openly express their dislikes. Thus, they only act aggressively toward other dogs in the familiar surroundings because that's where they have more assurance. We refer to this type of aggression as territorial/fear aggression.
Consider these observations on territorial/fear aggression: Naturally highly-strung breeds such as German shepherds, Australian shepherds, and Shelties are prone to displaying this type of behavior.
A dog that, as a pup, was nervous around other dogs, and barked at them or hid, is one that, later in life, may well display territorial/fear aggression toward dogs approaching the home or owner's car.
The posturing during displays of aggression can help distinguish this more anxious type of aggression from the territorial displays of a more confident dog. Territorial/fear aggressive dogs frequently show ambivalent body language the same as fear aggressive dogs, including approach-avoidance behavior, tucked or semi-tucked tail, slinking gait, averted eyes, and an indirect approach.
Territorial/fear aggressive dogs do not resolve their differences by means of a simple dominance-deference routine with the other dog and often will not settle down in the presence of a canine visitor.
The only distinguishing characteristic between territorial/fear aggression and overt fear aggression is the level of confidence that the dog possesses. Fear aggressive dogs have enough confidence to be aggressive to other dogs on or off their own territory, i.e. they display a higher level of dominance. Territorial fear aggressive dogs have a low level of dominance, permitting the expression of fear aggression only on the home turf or from within the safety of the owner's vehicle
Facts Concerning Territorial Aggression
Territorial behavior begins when a dog is young and "amplified" by learning.
Dominance-based territorial aggression is easier to manage than fear-based territorial aggression.
Both forms of territorial aggression may be controlled reasonably well by taking appropriate managemental measures.
The treatment program includes general management adjustments (plenty of aerobic exercise, a low protein diet, regular obedience training, use of a head halter for control, appropriate application of muzzles) plus specific behavior modification techniques (Nothing in Life is Free, Counterconditioning, Systematic Desensitization).
Owners of territorially aggressive dogs should keep doors secured to ensure that no dog can enter the property without warning. Territorial dogs should never be left outside unsupervised and unrestrained.
Electronic fences pose a particular problem for dogs with territorial aggression. The dog knows where HIS territorial boundaries are but other dogs do not, and may unwittingly cross the boundary. In general, territorial dogs are more aggressive when they are behind a fence of any kind - because a fence allows them to know exactly where the boundary of their territory lies. They will thus patrol and protect what is now well-defined turf. It best to install a solid fence. Solid fences insure that no passing dogs fall foul of territorial zealots and provide owners peace of mind ... and freedom from lawsuits.