20/10/2025
🐾 Why Dogs might show "Reactive" Behaviours
As a behaviour consultant, one of the most common concerns I’m asked about is when a dog barks, lunges, or growls at triggers such as other dogs, people, or moving things. Let's be clear, "reactivity" is the term given to overt physiological responses to underlying emotions
These sequences of behaviours are too complex to put under one umbrella term. Simply put, behaviour is communication and those communications are functional to our dog in that moment.
Here are some of the most common reasons dogs develop these behaviours 👇
🐶 Fear or past negative experiences
A dog who’s been frightened, startled, or hurt (even unintentionally) may react defensively to prevent it from happening again.
🐶 "flooding" or overexposure in early life - all of this should be done at your dog's own pace giving them control and agency over interactions and with new sights, sounds, smells and objects. Although adult dogs can develop reactivity due to "flooding" as well
🐶 Frustration or over-arousal
We can see this behaviour when our dogs are held back by a lead or fence. This is where a dog demonstrates a frustration-based reaction
🐶 Protective or guarding instincts
Dogs who are purpose bred to have specific ritualised behaviours to eliminate threats or guard their people or territory from anything that may be perceived as an “intruder.”
🐶 Pain or health issues
Even mild discomfort can lower a dog’s tolerance. A sore back, ear infection, or musculoskeletal issues make a even a previously comfortable, calm dog more defensive.
🐶 Unintentional reinforcement
Sometimes, our reactions, tension on the lead, raised voices, or pulling away, can reinforce the cycle of stress and reactivity without us realising it.
✨ The good news: Reactive behaviour can be changed. With patience, understanding, and the right approach, dogs can learn to feel safe and confident again.
If your dog is struggling with reactivity, please know you’re not alone- and it’s not your fault. With positive, science and evidence-based training, we can help your dog build better coping skills and restore calm walks again.