Why Does My Dog Bark and Lunge On Leash? (Intro to Reactivity)

Photo by Frank Pontier

All you want to do is take a nice relaxing walk with your dog like a normal person.

But every time your dog sees some trigger, be it a person or another dog, or perhaps a plastic bag floating on the breeze, they lose their marbles. Barking, lunging, and generally being an incredibly embarrassing pain in the ass.

This is called reactivity. It’s a severe overreaction to some everyday occurrence, like seeing another dog on a walk.

Reactivity is a blanket term; it covers a few different behaviors that look similar, but have different causes.

Today’s article will help you figure out which kind your dog has.

And don’t worry – reactivity sucks, but there is hope! See A Beginner’s Guide to Helping Your Reactive Dog Get Better

Reactivity can happen off-leash, but it’s usually seen on-leash. We don’t really think about it, because we’re so used to dogs wearing leashes, but wearing a leash can be stressful. It’s not natural, and it restricts their normal movement and behavior. It can exacerbate whatever negative feeling Fido is feeling, leading to reactivity.

(That’s not to say you should walk your reactive dog without a leash. That proooobably wouldn’t end well for anyone)

The two most common types of reactivity


Many dogs are afraid or uncomfortable in the presence of the trigger. Their behavior can look very aggressive, and it’s often mistaken for “just being protective” of their owner. But they’re scared, and that intimidating threat display is an attempt to make the scary thing go away.

For dogs who are even slightly fearful, being on leash can make their fear a million times worse, because they’re trapped.

Let’s say you’re scared of spiders. You’re at a park and somebody nearby is proudly showing off their pet tarantula. (Yes I know it’s a weird hypothetical. Just go with it)

You might be okay to watch from a distance – you’re free to walk away at any time. But what if someone twice your size grabs your arm and forces you to stand still while the tarantula owner comes closer? That’s pretty much what life is like for a fearful dog on leash.

Frustrated greeting/excitement

Fido sees another dog across the street. Being a sociable dude, he wants to go say hi. He starts heading toward the other dog, but he is stopped short when he hits the end of the leash. His enthusiasm can turn into frustration, which results in a reactive outburst. This is also called barrier frustration.

When you’re out walking your dog and you see another dog dragging his owner toward you, the dog barking and lunging and the owner saying “it’s okay! He just wants to say hi!” (no judgment, many of us have been that owner at some point), that’s an example of frustrated greeting reactivity.

Bonus: Combination-type

Another common type of reactivity seems to be a mix of both fear and barrier frustration. It’s sort of a “come closer but go away!” thing. These are dogs who really want to make some doggie friends, but are scared of those potential doggie friends. It may be that they’ve had bad experiences with dogs before, or they may have been severely punished for playing too exuberantly and now they think dogs = pain. Or they may be under-socialized and lack an understanding of dog body language, so they can’t tell if dogs are being friendly or threatening.

You may also see this in normal adolescent dogs who are going through a fear period.


Is reactivity aggression?

Aggression is defined as causing physical harm, or the intent to cause physical harm.

And the short answer is… not usually, but sometimes.

Most experts make a distinction between true reactivity and aggression. They consider the defining element of reactivity to be that it’s all show, very little substance.

It looks terrifying, but if the dog were suddenly able to reach their target, they wouldn’t attack. Their bark is literally worse than their bite.

This GIF is a perfect example:

But it CAN manifest as aggression. A dog reacting out of fear may resort to “fight” if the “flight” option is unavailable.

And dogs with frustration reactivity may “just want to say hi” but end up causing a fight anyway. Picture this: by the time they reach the dog they’re targeting, they’re super amped up and marinating in adrenaline. Their body language is nothing but rude, loud, intimidating gestures.

Understandably, this upsets the target dog.

The target dog may defend themselves. And in severe cases, reactive dogs may work themselves into such a frenzy that their exuberant greeting becomes an offensive attack.

But a dog who is consistently running after dogs or people to attack them? That’s not reactivity in the strictest sense – it would be classified as more serious aggression, which we’re not really addressing today. Owners of such dogs are welcome to keep reading, though. There’s a lot of overlap in the treatment of reactivity and aggression.

And for a candid discussion of this often arbitrary distinction between reactivity and aggression, see The Uncensored Story of How I Helped My Reactive Dog Get Better

What kind of reactivity does my dog have?

Knowing which kind of reactivity your dog has will be useful when coming up with a training plan to fix it (that will be our next post).

The big question: How does your dog behave off-leash around the trigger?

Say your dog’s trigger is other dogs. If she’s friendly and playful with dogs when everybody’s off-leash, it’s barrier frustration. Like a boisterous dog who lunges and hollers as she drags her human to the dog park gates, but is perfectly pleasant once they enter.

But if, off-leash, she avoids or ignores other dogs, or freezes when they approach to sniff her, you’re dealing with fear reactivity. Ever see a dog who looks big and tough while barking on leash or behind a fence, but as soon as that barrier goes away the dog seems to go “oh shit” and starts cowering or running away?

That’s a classic example of fear reactivity.

But what if you’ve never seen how your dog acts around their trigger off-leash? Figuring out your dog’s reactivity type will take more detective work, but it’s still possible.

(Please do not go to the nearest dog park and set your dog loose to see what happens. Recipe for disaster)

The fastest way to figure it out? Learn to translate dog body language

Having a solid understanding of “dog speak” will be critical when you start working on training to solve the reactivity, so ya might as well get started now, anyway. Take our free online course, Dog Speak 101. This course will:

  • Teach you to recognize the subtle signs of fear
  • Show you the difference between barrier frustration and a warning display, using video examples of dogs barking in shelter kennels
  • And more

Click here to sign up. (If you’re already a member of the 3 Lost Dogs Academy, you’ll find Dog Speak 101 waiting for you in your course library)

When in doubt

Sometimes it’s hard to tell. Especially if your dog has that weird combination reactivity. When in doubt, err on the side of caution and assume you’re dealing with some degree of fear or anxiety.

Is there actually hope?

Heck yes there’s hope! In the vast majority of cases, reactivity is highly treatable when you follow an appropriate, structured training plan.

Before we dive in to the how-to in the next post, I just want to say: I know this really sucks. Reactive dog life can be embarrassing. Suffocating. Isolating.

I get it. I see you. I know how hard you’re trying. You’re not alone. And together, we can help your dog chill out.

I won’t lie: it’s not exactly easy, and it takes time, and your fear-reactive dog will probably never be the social butterfly, dog-park type. But you can definitely make big improvements in your dog’s behavior. It will get better.

Next up: A Beginner’s Guide to Helping Your Reactive Dog Get Better

Do you know what your dog is saying?

Understanding the subtle ways dogs communicate is a critical skill for dog owners. It can help with choosing the right dog, solving training problems, and building a strong bond.

This free video course from our online academy will give you a basic, yet detailed, introduction to the wonderful world of canine body language and communication.

Want our help?

Follow us:

You might also like: