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Dog To Dog Aggression – Unfamiliar Dogs

Dogs Fighting

Some Of The Most Frequent Reasons Your Dog Might Be Aggressive Towards Unfamiliar Dogs

Table of Contents

Mother Nature

Frankly, dogs are by nature to various extents – territorial. Without appropriate guidance, a dog’s behavior will by default be driven by hormones, breed genetics, bloodline genetics, and evolutionary programs. Without the influence of a loving authority figure, things have a variety of ways of going south. Many companion dog owners, mostly due to being led astray by amateur dog trainers, believe that they are their dog’s loving authority figure. Still, the reality is their dogs see most as being somewhat closer to being a loving room-mate.

Appropriate guidance is by far the exception, as opposed to the rule. Unfortunately, the veterinary, vet tech, amateur dog training world, and the Internet, over the last twenty years seems to have subscribed to the idea that the movie the ‘Lady and the Tramp’ was a dog behavior documentary/template and have misled companion dog owners with well-meaning, but poor training guidance with regard to how dogs actually see the world, and how to approach their training and lifestyle maintenance.

One of the areas companions dog owners have been led astray is how they might expect their dogs to react to unfamiliar dogs. As a result, the dog’s instincts and hormones, breed genetics, bloodline genetics, and evolutionary programs are often exacerbated by factors as described below.

It’s worth keeping in mind that with few exceptions, for their ‘cousins’, the wolves, the appearance of an unfamiliar wolf usually ends in a narrow escape for that wolf, or death. Other wolves are thought to be the number one cause of death. In our somewhat less tooth and claw world, such concerns still linger beneath the surface in the Canis Familiaris, aka companion dogs. With what you read below further influencing in one direction or another, we can get one degree or another of reactivity.

There are other cases where the source of the behavior is more obvious: little to no social contact with their mothers and/or littermates during their critical imprint. In yet other cases, the behavior can be traced to the nonsense permitted in the horrible idea of “puppy socialization classes.” Another possibility is simply a random negative experience or two or three in the dog’s history.

Long story short while you aren’t going to change a dog’s nature, (or the nature of dogs) with the correct approach, you can teach them to respond to your direction to exert self-control.

Here are some of the contributing factors that frequently unnecessarily magnify ‘mother nature’:

The Dog's Age

In most cases, all may appear to be well while a dog is in the puppy stage of life as there is essentially a governor on both the pup and familiar adult dogs. The pup knows not to push too hard lest it triggers a familiar adult’s wrath for which it cannot physically cope. The adults will make allowances in the pup that they would be unlikely to extend to an adult dog. When encountering an unfamiliar adult dog, the puppy may exhibit signs of instinctive fear.

However, when a young dog hits somewhere between 12 months and 18 months of age, and if they reached that age without appropriate guidance they may decide that they’ve got what it takes to assert themselves.

The Dog's Gender

Sometimes dog-to-dog aggression is gender-specific and more likely to be so between the same gender, particularly if the dog has been used for breeding. More so with females vs males.

Breed and Bloodline Genetics

Some breeds are more inclined to be territorially competitive. Some are bred specifically to be so. However, all dogs have to a certain extent, an element of territorialism. 

Unsupervised Access Through Windows Or Yards

The natural aspect of territorial awareness/aggression that is inside all dogs can be exponentially and detrimentally magnified when (particularly in urban environments) a dog’s owner allows them to spend unsupervised time at a window or in a yard where their natural instincts are inevitably overly frequently triggered without supervision, and therefore guidance, they can and often are ‘trained’ to become excessive with regard to being aggressive, barking, etc. The reason being while being territorial has its evolutionary advantages, it was never meant to be triggered as frequently occurs when regularly looking out a window, or onto the street from a yard. Certainly not without supervision that was used to teach them how to exert self-control.

Genetics As Influenced By Breeder Negligence

In North America, knowing the difference between a male and a female dog is all that is required to breed a dog. It is almost unheard of for ‘breeders’ to followup on their bloodlines in a manner that concerns itself with and leads to increased bloodline and breed stability. They irresponsibly typically embrace the belief that ‘if there’s a problem, they’ll call.’

In the world of purebred dogs, the norm is breeding exclusively or predominantly for ‘show’ (fashion) as opposed to function and largely (and one might argue entirely) ignoring that far more critical long-term physical and mental stability, instead, in essence leaving it to ‘chance’. This has resulted in a multi-million dollar ‘Poor-bred’ dog breeding industry, rather than legitimately purebred, and stable dogs. Worthy of note, many ‘breeders’ claims to fame is membership with the Canadian or American Kennel Club, and that they have ‘bred dogs’ for multiple years. Consider how many people have a marriage license, have been married for multiple years, and yet aren’t particularly good at marriage, and you’ll get a sense of the value of such statements.

Additionally, designer dog ‘breeding’ is now considered acceptable and normal as opposed to being viewed as it should – completely lacking in ethics. ‘Designer breeding’ is the indiscriminate breeding of two different breeds,  and merging the breed names into something catchy.

If you would like to learn how to discern between an authentic ‘Breeder’, and a ‘Greeder’, have a look at this article:

The Nature Of The Relationship Between The Dog and The Dog's Owner

Relationship perceptions and the following item are far more significant as to whether and how intensely this characteristic rears its head. Instead of living with companion dogs as loving authority figures, most companion dog owners end up, due to the well-meaning, but poor advice provided by amateur trainers, veterinarians, vet techs, and rescues living with our dogs as loving room-mates. Without a clear idea through frequent reminders as to who is living in whose house, a dog is more likely to protect his or her territory and perceive a walk as a patrol.

Training Approach (Methodology Vs Ideology)

Sadly what now passes for training (treat-dispensing ‘All Positive/Purely Positive/Force-Free’) reinforces the idea of more a loving room-mate, rather than a loving authority figure, and this makes it far harder to meaningfully influence any dog beyond learning what is called obedience but is, in reality, nothing more than a short trick. That is not to suggest that ‘Might Is Right’ is the answer. For more on this topic, this eBooklet may be of interest:


Puppy Socialization Classes/ Puppy ‘Kindergarten’

Puppy socialization/kindergarten classes have become a favorite income stream for amateur companion dog trainers who, because of their amateur status, are unaware that to avoid fear, which all too often transforms into aggression, correct social imprinting must be much more than dogs meeting once per week for a few weeks. Dog-to-dog social skills imprinting is factually known to be complete by six weeks of age. This means before the pup leaves the breeder, let alone when a puppy socialization class is attended.

Ironically, what does happen in these classes often causes direct harm rather than good. The indirect harm occurs because companion dog owners’ understanding and efforts regarding exposure to the sorts of things that avoid fear and aggression are erroneously invested. That would be sound, sights, smells, and textures not ever found in a puppy “socialization” class—things like exposure to children in different stages of development, thunder, fireworks, traffic, etc. 

As the imprinting period (based on Scott and Fuller’s research) is limited to approximately 3-12 weeks of age, it ends up passing and, for many dogs, has a profound effect on their future quality of life. If you’re interested in learning more, you can read my book – Socialize Your Puppy for Everything – John Wade.

Puppies that go to these classes can from a dog-to-dog context, come out with one of three perspectives:

  1. No notable impact on the dog to dog socialization as that period is well past and the beginnings of addiction to treats as a means for motivation.
  2. A fear that they may be bullied by dogs they are unfamiliar with.
  3. The belief that they can get away with bullying dogs they are unfamiliar.

The Good News

Long story short, while we may never persuade a dog to love other unfamiliar dogs, almost all dogs can be taught to exert self-control, if the owner can find a trainer that is not an amateur to help them learn how to do so. Here are a couple of resources to learn more:


When The Aggression Is Really Bad

This article can act as a ‘thinking the problem through’ workflow.

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