The staff here at K9 Connection, including myself, recently completed a workshop in canine socialization which had it’s main focus on understanding the causes and dimensions of inter-canine aggression.

The workshop leader Chad Mackin (founder of the Pack to Basics program, and board member of the International Association of Canine Professionals) outlined a model of aggression that he termed the “Layered Stress Model of Aggression.”

Although it may be argued that standing alone this model does not represent a complete understanding of the causes of aggression, I believe that it does supply a very practical vantage point that every dog owner can benefit from.

The Layered Stress Model essentially says:

1. Every dog has a pre-determined stress threshold, beyond which they can potentially become dangerous.
2. The stress threshold itself is generally unchangeable.
3. Various factors in a dog’s life can add “layers” of stress, each of which brings the dog closer to their threshold point.
4. Layers of stress can be diminished or eliminated by: a) removing the stressor, or b) changing the dog’s response to that stressor through counter-conditioning.
5. The more “layers ” of stress we remove, the less likely any one specific event is to push the dog beyond the threshold point and result in aggressive behavior.

This model is very practical if we begin to look at the behavior of an individual dog.

Lets take an example of “Snarly” the terrier.

Snarly has a history of being very reactive when company come over to the house. He is fine as long as people are sitting down and behaving relatively calmly. However, if someone gets up to use the bathroom or makes a sudden movement, Snarly will get up and lunge at the guest potentially biting.

The action of someone getting up or making a sudden movement is for Snarly a specific stressor that pushes him beyond his threshold, thus putting him in the danger zone. While it is appropriate to work with this specific context by desensitizing Snarly to peoples movements and counter-conditioning him to respond differently. It can be of great importance to also look at other areas of Snarly’s life and work to remove or reduce any layers of stress possible.

To be more clear, lets give numerical values to stress. Lets say that Snarly’s threshold is 150 units on the stress scale. What this means is that if his stress level goes beyond 150, he is likely to snap.

Now lets look at various things in Snarly’s life. Snarly lives with very inconstant humans, who don’t always give clear commands that he understands, but rather tend to speak to him in full sentences that he has to decipher. The confusion adds a relatively constant stress level of 20 to Snarly’s daily life. Snarly also does not get regular physical exercise, and often has pent up energy which leaves him feeling a little “edgy”, this pent up energy adds another 30 to Snarly’s stress level. Snarly also is getting older now and is developing some arthritis in his joints, this discomfort ads another 30 to his stress level.

So before guests have even arrived, Snarly is living with a stress level of 80. This medium level level of stress may not be visibly apparent to his owners, but it is there regardless.

Now arrive the guests, and having strangers in the house adds 40 more stress points. And finally, quick moments by those guests add 50 more stress points. We suddenly find poor Snarly’s stress level at 170! Well beyond his threshold and he snaps.

If you are like me, you can relate to Snarly’s situation. When I have a bad day, it typically is compiled of lots of small stressful events that continue to build. Eventually one small thing, something that normally is very tolerable, puts me over the edge, and I snap.

So, if we really truly want to help snarly, we need to look at the whole picture. Lets add constant consistent obedience training and clear human leadership to Snarly’s life. This brings stress of living with humans down to 5. Let’s also add consistent structured exercise to Snarly’s daily routine in the form of controlled walks, and playtime with his humans in the back yard (not by himself). This eliminates the stress caused by the edgy feeling of pent up energy. We also take Snarly to the veterinarian and add a supplement to his diet to help with his arthritis, thus reducing the discomfort. Bringing the stress from that condition down to a 10.

Now we have reduced Snarly’s daily stress level to down to 15. See where I’m going here?

Company then arrives, adding 40, somebody makes a sudden movement adding 50, we still are only at an overall stress level of 105! Suddenly Snarly isn’t biting people anymore.

Of course, dogs are creatures of habit, so unless we started making this changes very early in Snarly’s biting career, it is likely that he has developed a conditioned response to people moving around. However, since we have removed enough stress, counter-condition this behavior and teaching Snarly to lay calmly in his his bed is now a breeze, since he is well below his threshold of stress, and thus perfectly capable of coping with those actions.

This is lead dog trainer Josh Moran’s dog King. Here he shows how a dog NEEDS to behave around the road.