He spots a dog at the end of the street. His body tenses, his gaze locks, then he barks, growls, pulls on his leash, or lunges abruptly in its direction.
The verdict sometimes falls immediately:
“That dog is aggressive.”
Yet, two dogs capable of producing exactly the same scene may have completely different motivations. One might be trying to distance himself from what scares him, while the other is frustrated at not being able to reach his fellow dog.
This is one of the essential elements to understanding reactivity: the reaction we see does not automatically tell us why it is happening.
What do we call a reactive dog?
We generally speak of reactivity when a dog produces a particularly intense response to certain stimuli.
He may bark, growl, lunge, pull violently on his leash, freeze, or become extremely difficult to distract from what he is observing.
The trigger can be another dog, a human, a bicycle, a car, a noise, a movement, or an animal. Some dogs only react to a very specific situation; others accumulate several triggers.
Saying that a dog is “reactive” therefore describes above all what we observe. It is not, by itself, a diagnosis or an explanation.
To understand the behavior, we must look for what triggers the reaction, at what distance it appears, what happens just before, and what occurs immediately after.
Fear: increasing the distance
A dog can react because he is trying to push away something he considers threatening.
Imagine he spots a fellow dog, barks violently, and charges at the end of his leash. The other owner then decides to walk away.
From the reactive dog's point of view, an important thing has just happened: what was worrying him has moved away.
If this situation repeats, the behavior may be maintained because it seems to produce the desired result.
In this case, systematically forcing proximity is not necessarily the solution. Instead, the work may begin at a distance where the dog remains available enough to observe without immediately tipping over into reaction.
Frustration: wanting to join without being able to
Another dog may produce almost identical behaviors for the opposite reason.
He spots a fellow dog, absolutely wants to reach him, but the leash prevents him. He pulls, vocalizes, barks, and ends up producing a spectacular reaction.
From the outside, the scene may resemble that of the dog trying to distance his fellow dog.
However, one wants to increase the distance while the other seeks to reduce it.
Applying exactly the same response to both dogs without seeking to understand this difference risks missing the real problem.
Excitement and difficulty calming down
Some dogs escalate in excitement very quickly. They observe their environment intensely, react to the slightest movement or sound, and seem constantly on alert.
An additional stimulation may then be enough to provoke a very strong reaction.
In this case, working only on “no longer barking at dogs” may be insufficient. The work may also focus on the dog's ability to navigate his environment without constantly remaining in a state of hyper-activation, and on his ability to return to a calmer state after a stimulation.
The recovery time is, moreover, a particularly interesting piece of information.
Two dogs can produce a reaction of the same intensity, but one may regain his calm in a few seconds while the other remains tense for several minutes.
Reactivity and predation: don't mix everything up
Predation must also be distinguished from classic social reactions.
Staring, chasing, and attempting to capture a moving animal belongs to a different behavioral sequence than a defensive reaction towards a fellow dog.
A dog that chases a cat, a deer, or another animal should not, therefore, be automatically analyzed in the same way as a dog that barks when a fellow dog approaches.
The visible manifestations can sometimes look similar, but their function is not necessarily the same.
Looking at what happens before the explosion
Barking, growling, or charging are the most visible behaviors. Yet, the most interesting information often appears a few seconds beforehand.
The dog may slow down, close his mouth, alter his posture, freeze, stare, change the position of his ears, shift his weight forward or backward, seek to move away, or become suddenly much more vigilant.
Not all dogs show exactly the same signals.
Learning to know those of one's own dog, however, allows for identifying the moment when the situation begins to become difficult before reaching the explosion.
The threshold: working before the dog is overwhelmed
Imagine a dog can calmly observe a fellow dog located thirty meters away. At twenty meters, he begins to stare. At ten meters, he has difficulty responding to his human. At five meters, he barks and lunges.
Systematically starting work at five meters is equivalent to starting the exercise at the moment when the dog can no longer manage the situation.
Distance therefore becomes a real tool.
We first look for a zone in which the dog perceives the trigger while remaining available enough. When this situation becomes easier, the difficulty can evolve gradually.
And the goal is not necessarily to one day arrive at fifty centimeters.
For some dogs, crossing calmly at several meters and continuing on their way already constitutes an excellent success.
The leash can modify the situation
The way the human uses the leash can also influence an encounter.
When a dog appears in the distance, his owner may anticipate the reaction, immediately shorten the leash, tense up, and maintain constant tension. The context then changes before the two dogs even cross each other.
This obviously does not mean one should give several meters of freedom to a dog likely to charge.
Safety remains the priority.
The objective is rather to learn to manage the leash in a sufficiently safe manner without adding unnecessary permanent tension when the situation does not require it.
A reactive dog is not obligated to like other dogs
This is a goal sometimes imposed unnecessarily.
A dog does not need to play with all his fellow dogs to be balanced or properly trained.
For some reactive dogs, managing to spot another dog, continuing their path, and quickly returning to something else already represents a considerable result.
Neutrality is a perfectly valid goal.
The priority is to obtain a situation sufficiently controlled to protect the dog, his human, and the people or animals encountered.
Reactivity does not automatically mean aggression
An aggressive behavior can obviously appear during a reaction: growling, threatening, attempting to bite, or an actual bite.
But immediately labeling the dog as “aggressive” still does not allow for understanding why he is acting that way.
Some approaches will seek primarily to quickly reduce the visible manifestation. Others will work more on distance, emotion, or association with the trigger. Still others combine management, training, and a more directive framework.
These approaches can act on different components of the problem.
The important question is therefore to know what we are trying to modify: only the visible manifestation, or also the conditions that cause its appearance.
Interrupting a reaction and solving the problem are not always the same thing
A dog that immediately stops barking during a session may give the impression that the problem is solved.
Sometimes, a clear interruption is indeed necessary, especially when a behavior becomes dangerous. But obtaining silence does not, by itself, allow one to know the emotional state of the dog or how he will react tomorrow in another situation.
Conversely, working only on emotion without having a way to concretely manage the dog during the learning period can also pose safety difficulties.
Immediate management and underlying work can therefore be complementary.
This is particularly important in reactivity: the dog must be able to learn, but his human must also be able to maintain control of the situation.
What can you start working on yourself?
When reactivity remains moderate, the dog remains physically controllable, and there is no immediate risk of biting, the owner can already perform very useful work.
He can identify the triggers, observe the distances at which the first signs of tension appear, avoid unnecessary confrontations, and choose environments that allow for maintaining sufficient space.
He can also observe the time necessary for the dog to recover after a reaction and look for situations in which the dog succeeds in perceiving his trigger without exploding.
Noting these elements sometimes reveals patterns that were previously invisible.
When should you call a trainer?
It is not necessary to wait until the situation has become uncontrollable.
The intervention of a professional becomes particularly relevant when the owner can no longer guarantee safety, when the dog drags them physically, when he attempts to bite, or when a bite has already occurred.
It is also preferable to ask for help when triggers multiply, reactions become gradually stronger, it becomes impossible to find a distance at which the dog remains available, or each walk becomes a succession of difficult situations.
And there is a much simpler reason to consult:
no longer understanding your dog.
An outside perspective sometimes allows for identifying elements that have become difficult to perceive when living with the problem daily.
How to choose the professional?
Reactivity is a domain in which it is particularly important that the professional observe the dog before applying a ready-made solution.
He should seek to understand the triggers, the distances, the context, the signals preceding the reaction, what happens afterward, and the speed at which the dog recovers.
He must also take into account the capabilities of the human.
A technique that is theoretically effective but impossible to reproduce correctly by the owner in their daily life will necessarily have limits.
The professional must therefore work with the human-dog pair, not just with the dog during a session.
When should you consult a veterinarian first?
All reactivity is not just a question of training.
A sudden change in behavior notably deserves searching for a possible medical cause. A previously tolerant dog who suddenly becomes irritable, aggressive when touched, or unusually reactive may be suffering from pain or another health problem.
In this case, a veterinary consultation is indicated.
For certain complex behavioral situations, collaboration between a veterinarian and a behavior professional may also be necessary.
And when safety is at stake?
Understanding the dog must never make one forget safety.
A dog presenting a risk of biting may require much stricter management of his environment during the work: choice of walking locations and times, sufficient distances, adapted equipment, or progressive and positive training for wearing an appropriate muzzle.
These are not educational failures.
They are prevention measures that allow for working precisely without putting the dog, his human, or others in danger.
Understand before trying to eliminate
Reactivity is not a single diagnosis. It is a visible manifestation behind which very different mechanisms may be found.
Two dogs can bark. Two dogs can pull. Two dogs can charge.
And yet, they may have two completely different problems that will not require the same work.
The first question should therefore not be only:
“How can I stop my dog from reacting?”
One must also ask:
“Why is he reacting? To what? At what distance? Under what circumstances? What happens before and after his reaction?”
It is based on these answers that one can choose an adapted method, set a realistic goal, and determine if one can continue the work alone or if it is preferable to be accompanied.