©Scott Sheaffer, CDBC, CBCC-KA, CPDT-KA, USA Dog Behavior, LLC
Most people think of dog aggression as the only diagnosis needed when assessing a dog that is presenting with agonistic behaviors such as barking, growling, biting, lunging, etc. The reality is more complicated.
“The probability of in-home aggression increases exponentially as the number of dogs increase…”
There are seven major types of dog aggression and each has a unique root cause. To effectively treat aggression in dogs, it’s important to understand the details of each case because each kind of aggression requires a different treatment plan. In many cases, dogs simultaneously present with more than one type – known as a comorbid diagnosis.
I’ve identified seven major categories of canine aggression below.
Fear aggression is the most common type of aggression that I treat.
An offensive posture is taken by the dog to increase the distance from the trigger (e.g., human, dog, etc.). In short, the dog takes an offense-is-the-best-defense approach.
This type of aggression can also be directed at inanimate objects (e.g., vacuum cleaners, skateboards, cars in motion, etc.).
Fear aggression can also simultaneously present with avoidance behaviors (i.e., dog tries to escape from the trigger) in addition to agonistic behaviors and is known as an ambivalent presentation.
Territorial fear (also known as sentry dog or junkyard dog) aggression is a type of fear aggression that is directed toward humans in the dog’s designated “territory”. It is the second most common type of aggression I see.
Dogs presenting with this type of aggression can appear perfectly normal outside of their “territory”.
The intensity of the aggression is normally fairly significant.
The dog’s “territory” is typically the inside of the owner’s home but frequently extends to the property surrounding the owner’s home and even beyond that.
Idiopathic (also known as rage) aggression is an unpredictable type of aggression because the triggers aren’t known or understood. The word “idiopathic” is defined as, “relating to or denoting any disease or condition that arises spontaneously or for which the cause is unknown”.
This type of aggression can be very dangerous because it includes sudden and severe outbursts with little to no warning.
Treatment options are limited.
Some of the most aggressive dogs I deal with are in this category.
Prey aggression is really not aggression at all in my opinion. Your dog is not angry or afraid of that squirrel or rabbit; he just wants it for lunch.
Considered extremely pathological if directed toward humans.
A common diagnosing attribute is silence and slow, deliberate movements.
After seeing literally hundreds and hundreds of dog aggression cases, I’ve seen only two cases of human directed prey aggression - and they were quite disturbing.
In-home (also known as sibling or intra-household) aggression is the third most common type of aggression that I treat.
Indicated when two or more dogs living in the same home display chronic agonistic behaviors toward one another.
The probability of in-home aggression increases exponentially as the number of dogs increase; four dogs in one home is a common tipping point.
Can be challenging to treat because the dogs are constantly in close proximity.
Control related (also known as dominance, owner directed or conflict) aggression presents as a learned aggregate of aggressive behaviors that have been taught to the dog through improper handling and management of the dog.
Have you ever been in a home where the five-year-old child is a screaming tyrant while the parents stand around with a deer-in-headlights look on their faces? Substitute the dog for the child and you get the idea.
Aggression is primarily directed at owners or those with whom the dog frequently interacts.
Can appear terrifying to dog owners but frequently has a good prognosis with a proper behavior treatment plan.
A common mistake dog trainers and dog training companies make in treating this type of aggression is using punitive or aversive measures. This error is caused by misdiagnosis and lack of understanding of proper treatment protocols for this type of aggression.
Commonly seen in first-time or inexperienced dog owners.
A sad and normally preventable type of aggression.
Possession (also known as resource guarding) aggression is when dogs keep other dogs and humans away from their food, treats, toys, space, owners, other dogs, etc.
While it appears not to be a fear-based aggression, some argue that the dog is fearful of losing a valued resource thus making it fear-based in actuality.
A sub-type of possession aggression is distance resource guarding. In this form the dog will monitor things from a distance and rush to the dog or human near the resource-guarded item and aggress.
This type of aggression is particularly susceptible to escalation.
If your dog is presenting with one of the types of aggression noted above, please seek the help of an independently certified dog behavior consultant. Using ill-advised techniques, such as punishment for aggressive behaviors, normally makes things worse in the long run. Since aggression in dogs almost always escalates over time, the early stages are the best time to start a treatment plan.