Summary
Resource guarding is a term used to describe appropriate or inappropriate behavior surrounding the possession of a prized resource. This typically involves the custody of food and objects (toys, bones, and other treasured items), but may include control over locations (preferred bedding or sunny spots) and even water resources.
Though it's observed in cats as well, for the purposes of this article, canine behavior will be addressed, as this behavior is typically only problematic in this domestic species.
Appropriate resource guarding behavior in dogs involves the acquisition and guarding of a high-value item. This may comprise perfectly normal behavior in dogs. It becomes problematic when this behavior results in undue stress on the guarder or should it potentiate risky interactions between dogs. It becomes especially problematic should it lead to dangerous interactions between humans and dogs.
It's believed that problematic resource guarding behavior may be, to some degree, inherited. It may, however, also be stoked by conditions of deprivation (scant resource conditions that led to starvation, for example) and owner exacerbation (as when owners ill-advisedly employ aggressive dominance techniques in an effort to secure "alpha-dog" status). In most cases, a combination of these factors can be assumed.
Other environmental factors that may influence resource guarding include the use of medications that may increase appetite. There are several common medications that have this side effect.
Symptoms and Identification
Resource guarding is readily identified when dogs defend their claim to an item via one of a number of means: This runs the gamut from running and hiding, offering submissively appeasing gestures, and tightly clenching the object in their mouths to growling, barking, snapping, and even lunging.
Though it's clear that some dogs will never exhibit violent behavior, differentiating between normal and abnormal resource guarding can be difficult. For example, some dogs that never display aggression may nonetheless become excessively anxious in these situations. Others may go as far as to growl, yet still lie within normal limits for resource guarding behavior.
Those who display this behavior inappropriately tend to exhibit one or more of the following signs of problematic guarding behavior: displaying dangerously aggressive behavior towards humans or other dogs, appearing to be highly anxious during the event, and difficulty calming down after resolution of the incident.
In most cases deemed problematic, there's no bright line that divides the severely affected from the mildly affected. However, dogs that aggressively pursue anyone in the vicinity while guarding their prized possession should for all intents and purposes be considered severely affected.
It's important to note that dogs who become anxious during these events are more likely to have anxiety-related behavior problems.
Affected Breeds
It's difficult to assign a breed-specific designation for this behavior. A combination of genetics and environmental influences is assumed.
Treatment
Resource guarding behavior is often readily dealt with via a technique referred to as avoidance. Quite simply, this means that the dog is never put in a position where he or she will need to guard an item. So when resources are present, people and other dogs (depending on the recipient of the negative behavior) are kept at a distance.
Feeding dogs separately and/or otherwise offering them highly valued resources only while confined is always recommended.
Veterinary Cost
Resource guarding is usually not considered terribly expensive. That is, unless the resulting negative interactions lead to healthcare concerns for humans and/or should serious dog fights ensue and veterinary care become necessary.
Severe resource guarders should be referred to a veterinary behaviorist, in which case expenses assumed here may not be limited to treatment of resource guarding. For these patients, treatment of a wide range of anxiety-based issues is typically in order. This may cost upwards of $500 to $2,000 or more, depending on the severity of the anxiety.
Prevention
As mentioned above, resource guarding is generally best addressed by preventing the behavior to begin with. See above.
References
Behavior modification in action. ASPCA:aspcapro.org/behavior-modification-in-action.php
Food Aggression. Animal Rescue League of Boston: centerforshelterdogs.org/Home/DogBehavior/ProblemsandManagement/FoodAggression.aasp
Preliminary investigation of food guarding behavior in shelter dogs in the United States. Mohan-Gibbons H, Weiss E, Slater M. Animals 2:331-346, 2012.