Wednesday, March 23, 2011

Resource Guarding Aggression


The Aggression Question, Part 2: Resource Aggression

We are discussing aggression, and aggressive display, as a response to environmental stimuli. But we need to remember, as a refresher, that we must address the reaction to the stimulus as seen by the dog, not a human observer.

We must remember is that the dog is responding to the perception of the stimulus. Perception is dependant on a number of factors, including the dog’s past experience, training, socialization, physical limitations (hearing, sight, etc.), reproductive status, and nutrition level. The dog’s perceptions may not be grounded in objective reality. 

We have defined aggression as a behavior pattern that allows a dog to change or alter its environment in some fashion.  We have listed three specific incidences in which aggression has value; response to perceived threats, protection of resources, and altering of social status.  We have discussed perceived threats, so let us move on to protecting resources.

Protecting resources is easy for humans to understand. All animals need certain basic resources; food, water, shelter from adverse environmental factors, and reproductive access (if the species is going to survive).  In times of plenty resource protection may be relaxed somewhat.  In times of scarcity, resource protection is vital and can be a life and death struggle.

Our pets generally operate in an atmosphere of plenty.  Except in rare cases (post-Hurricane Katrina for instance) our domesticated pets do not have to fight for food access.  Begging at the table works fine.  But these drives still exist, and can affect our day to day interactions.  We have all seen the dog that growls when someone approaches while they have a favorite toy or food item.  This favored item is a resource, and the dog in question is guarding that resource.

The drive to protect resources is powerful and hardwired into animals.  Some dogs react to the presence of a resource as if they are likely to be in a scarcity situation and therefore, to protect that resource, use an aggressive display.  Audible signals such as growling combined with visible cues such as raised hackles and bared teeth serve to warn an approaching animal (even a human one) that the resource is not for sharing.  This warning may not be dependant on a true likelihood of scarcity or pending removal of the resource; the key here, as always, is the perception of the dog at the time of the incident.

Ideally these cues progress from a low level warning (audible growl followed or accompanied by initial level visual cues) through a forceful audible warning (bark and loud, overt growl/snarl) to a full frontal bare teeth snap and lunge, ultimately culminating in contact and a bite. If the initial bite does not deter the perceived resource threat then a full fight may ensue, depending on how attached the initial possessor is to the resource.

This sequence may be interrupted by several occurrences.  The possessor may, depending on the size and status of the offender and the perceived value of the resource, decide that the resource is not worth defending and withdraw the defense. The offender may similarly evaluate the size and status of the possessor and decide the resource isn’t worth fighting for. Withdrawal of either party may occur after an exchange of communication signals that result in a mutual appraisal and agreement over this particular resource. After all, the survival of a species is not served by every conflict devolving into a fight over every resource. That would result in a population of injured and dead animals that would not be viable long term.

We usually teach our dogs not to blatantly guard resources.  Many training books over the years have strongly suggested that we, as owners, teach puppies to “share” by taking food and toys away from them at will, and then returning them, so the puppy does not develop resource guarding behavior.  This is a good safety measure. But not all dogs are adequately socialized and trained to recognize humans as non-threatening to resources.  In fact some humans are valid threats to resources. A dog that has been habitually short of nutrition may have perfectly valid reasons not to surrender a treat or bowl of food to a human.

This gets us into trouble when a child, or a person unable to perceive these warning cues, persists in the perceived removal of the resource. In the case of a person that fails to recognize such cues and continues with a behavior the dog perceives as interfering with his resource, the dog follows a predictable sequence of protective moves. The sequence of warnings and escalation may happen very quickly; dogs interact rapidly and this progression may, in normal dog-dog interactions, flow through in a flash. Dogs perceive interspecies signals very quickly and can evaluate the sometimes subtle nuances in rapid sequence.

The sequence of negotiations and postures make sense to the dog and are part of its hardwired behavior. The human target of the dog’s warnings may not be able to respond quickly enough to avoid escalation, or the human may not understand dog signals, and fails to either redirect his or her behavior or adequately negotiate with the dog. The dog follows the (to him) logical “use of force matrix” and a bite, perhaps even a serious attack, follows.

Resource protection goes beyond simple food and toys. Protection of territory is a version of this, as the animal’s territory is often the source of food, water, shelter, and in some cases his/her breeding stock. Humans may not perceive the limits of a dog’s territory. Many times physical boundaries, such as fences and brush lines define a territory visibly, but that is not an absolute indicator.  An individual dog may regard a smaller area inside an otherwise physically delineated area as his actually territory worth defending-or may consider an area outside the physically defined space as territory. This is one of the ways humans such as utility workers, meter readers, and others get bitten; the particular dog may let them into the fenced yard, but when the worker violates the dog’s personal territory the dog’s demeanor changes and a confrontation ensues.

Is an attack or confrontation in such a resource guarding situation aggression? Yes, as we have defined it-aggression is a strategy to affect its environment for survival by protecting resources. To adequately evaluate the aggression the investigator must consider the potential of resource protection from the dog’s point of view. Was the bite victim within the dog’s perceived resource territory? Was the human perceived to be threatening the dog’s access to one of the key resources? In such a situation the aggressive response may well be understandable, and even a logical response. Should this response have been anticipated and guarded against by the owner through training, socialization, and even management? That determination is a central portion of the investigator’s job.

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