Many species of animals guard territories – geographical areas they have claimed for themselves due to the availability of food, nesting sites, and other valuable resources. Birds, marine mammals, primates including humans, and land mammals like our beloved domestic dogs, have been known to guard land areas.
Most territorial behavior is demonstrated toward members of the same species. Dogs primarily display ritual behavior, such as raised hackles, urinary marking, growling and barking. Offensive signals – standing tall, tail high and ears forward – are usually associated with territorial aggression. As impressive as the displays may be, for most species, actual aggression is the exception rather than the rule.
Canine aggression is heightened under domestic conditions because territories are usually relatively small, share common boundaries and are often crossed by intruders. Some behavior professionals suggest that “fence fighting” is a common example of territorial aggression in which the fence is the territorial boundary for the intruder as well as the defender, with both dogs laying claim to the dividing line. Others theorize that barriers such as fences or closed car windows make the dog feel safe and therefore braver.
Aggressive behavior is enhanced when the absence of a physical barrier allows intruders to trespass at will through a dog’s territory, as is the case with dogs kept on chains or inside invisible electric shock fences. Hence, an adaptive behavior designed to avoid aggression in nature – ritual territorial display in a large territory – actually increases the likelihood of aggression in the domestic dog in artificially small territorial spaces.
The Defended Area
Most behavior professionals include the dog’s yard, car, kennel and the entire interior of a house (or selected spaces within it) as territory. Since humans and possessions often occupy the defended area, protective aggression as well as defensive or fear-related aggression are sometimes mistaken for territorial aggression – and vice versa. To determine if your dog is demonstrating territorial aggression, remove him from his perceived territory. If the aggression stops, he was likely being territorial. If your dog is aggressive in your presence, but not in your absence, then it is most likely that he is exhibiting protective aggression.
Environmental Management
In the case of aggression, it is important to manage your dog’s environment to avoid anyone getting injured. Your dog perceives people entering his territory as a threat. Modifying his behavior relies on changing his perception of them from intruder to welcome guest. In many cases, you can prevent territorial aggression by being careful about where and how you keep your dog. The aforementioned practices of chaining and using electric shock fencing are not recommended. A solid privacy fence is the best choice as it minimizes visual stimuli that can lead to territorial aggression. Supervision while your dog is outside is also recommended.
Work with your dog by giving him delicious treats anytime a new guest arrives or a neighbor walks by. You can change your dog’s bad association with intruders by associating the appearance of an intruder with something wonderful. You will need to practice often with a variety of different people in various settings in order to successfully modify his reaction. It will take time, so be patient. If you have any doubts about your ability to work with your dog safely, or if you’re not making good progress after a few weeks, be prepared to consult with a qualified positive behavior professional. Contact your veterinarian for a referral.
Cummings School of Veterinary Medicine at Tufts University “Your Dog Magazine”
