How to manage dog on dog aggression

How to manage dog on dog aggression

Does your dog display aggression toward other dogs? Here’s what you need to know about this unwanted behaviour before you can hope to manage and prevent it.

If you’ve ever seen a dog fight, you know how scary they are to witness. Results can range from a bit of saliva on the fur, to deep puncture wounds, muscle tearing, broken bones and occasionally even death. Most fights between two dogs are what we call ritualized fights – full of sound and fury but signifying very little. Interestingly they usually sound much worse than serious dog fights and can be extremely distressing for the pet parent. It often comes as a surprise that neither of the combatants has any wounds. But wounds or no wounds, these brawls are frightening. So how can you prevent them from occurring?

Types of aggressors

Like the fights themselves, all dog aggressors are not equal. We’ve probably all encountered the various types, one of which is “the Tarzan”. Tarzans have no evil intent but are often into body slamming, growling, and possibly mounting, and they don’t back off when the other dog delivers appropriate “back off” body language.

“The shrinking violet” is the opposite of a Tarzan. Socially shy, the shrinking violet often displays fear and avoidance by lunging, barking and snapping until the other dog is far enough away.

Then there’s “the old dog”, or “the crank”.  The old dog is undoubtedly arthritic and would react very badly to Tarzan’s body slams.

Knowing the types of dogs in a particular play group or walking group can help pet parents orchestrate safe encounters.

Nature versus nurture

The “nature versus nurture” debate applies to dogs just as it does to humans. Certainly training and proper socialization can make a world of difference to any dog’s behaviour, but training isn’t the whole story. Some dog breeds are, in fact, best to be avoided as family pets, such as dogs initially bred to guard and fight.

Such dogs may be okay with people, but when it comes to other dogs, they often have very poor bite inhibition. They may also continue to fight even when the other dog is doing all the right things to inhibit aggression.

The job a dog was bred to do will give you a good indication of what kind of pet he or she is likely to make. The traits that make certain breeds good at jobs like hunting big game, or guarding people and property, make them too much of a challenge for all but the most experienced dog parents. There’s a reason dogs like Labradors and Golden Retrievers, bred to work alongside people and often used as therapy or guide dogs, remain popular year after year as family pets.

A behaviourist’s approach to dog aggression

A lot of anguish can be prevented by taking a behaviourist’s approach to aggressive behaviour. This approach dictates that, rather than labelling behaviour as good or bad or agonizing over the dog’s underlying motives, the pet parent leaves emotion behind and concentrates instead on changing undesired behaviour using positive methods proven effective over time.

An example would be on-leash dogs that respond aggressively to other dogs approaching them. The worst thing the handler can do in this situation is to tighten the leash, or shout, or pull the dog away. This confirms to the dog that there is indeed something to worry about.

“If you are a dog owner and your dog fights, bullies, is difficult to manage on leash or seems uncomfortable around other dogs, get yourself into the hands of a competent professional.” – Jean Donaldson, FIGHT! A PRACTICAL GUIDE TO THE TREATMENT OF DOG-DOG AGGRESSION. Kinship Communications, 2004.

The best thing to do is to create, over time, a good conditioned emotional response (CER) by pairing the presence of a new dog with something positive, like a food reward. There should also be a lot of happy verbal praise if the dog can accomplish some behaviour, such as sitting on cue, that is incompatible with aggressive behaviour.


Not many dogs will make it to the end of their lives without having at least one fight with another dog. That being said, it’s important to manage your own canine companion appropriately based on his bite history. If a fight erupts, is your dog likely to cause serious injury? Then it’s your moral obligation to take steps to make sure a fight doesn’t occur.

While most dogs don’t fall into the category of serious fighters, we as pet parents have a responsibility to both our pets and to the public to create well-mannered, non-aggressive canine citizens. Training class is an ideal place to start. A well-run training class is ideal for socializing pups and teaching them good bite inhibition.

Professional dog trainer Jill Kolar, one of the founding members of the Champlain Dog Club in Petawawa, Ontario, has been running puppy classes for the Pembroke Animal Hospital for over twenty years.  These classes include carefully supervised off-leash play sessions where pups learn social skills and manners. All pups must be vaccinated, says Jill, and must still have their puppy canine teeth.

Puppy classes (or, in a pinch, ad hoc “puppy parties”) are great for socialization, but socialization shouldn’t end when the pup becomes an adult. Opportunities to interact with other safe dogs should be sought on a regular basis.

Despite everyone’s best efforts, problems might still occasionally arise that preclude such interactions. The solution is often as simple as removing your dog from a particular situation, says Jill. “Listen to your dog,” she adds. “Let him tell you when he’s okay with something and when he’s becoming uncomfortable.” Often leaving a situation is all it takes to avoid a reactive response or confrontation.

Some possible causes of aggression towards other dogs:

  1. Pain or a medical issue. If this is suspected, a veterinarian should be consulted.
  2. Resource guarding. This is often seen in dogs that will share a space but not a delicious bone.
  3. Fear.  The dog feels that he is in some sort of imminent danger.
  4. Frustration. The dog is being pestered or is confined by being chained or on a leash and so not able to react naturally.
  5. Dominance.  Dominance is a behaviour, not a trait, and should be treated as such.