Startle…and Attack?

Lustiger LabradorDogs have an instinctive startle reflex, just like humans do. Upon hearing a loud noise or being touched when not expecting it, most of us, human or canine, will startle. It’s a good thing we do, because that automatic response keeps us safe from predators and other dangers. The startle reflex is often put to use in traditional temperament tests where, for example, a ring of keys is dropped near a litter of puppies. All the pups naturally startle, but some will run and hide while others will recover quickly. This test is meant to gauge the pups’ confidence level.

Although a startle reflex is a good thing, some dogs when startled don’t simply jump or flinch. Instead, they display what might be perceived as aggressive behavior. For example, some well-meaning owners have kissed their sleeping dog on the head, only to be bitten in the face. This reaction on the part of the dog is simply that—an instinctive reaction and one that, if there were something to truly be feared, would protect the dog. I imagine that just like people, some dogs run or cower when startled, while others lash out. This is not the same thing as aggression, although that’s how it often gets labeled.

A dog snapping at something that startles him at close range is understandable. But my girl Sierra does something different; she doesn’t snap at my husband or me, but if a sudden noise across the room startles her—for example, the popping of a champagne cork—she’ll race directly to it and snarl at it. (This does not impress the champagne, which goes right on bubbling.) The more unfortunate scenario at our house is when both dogs are lying on their beds, which are next to each other, and Sierra is startled by someone dropping something like the television remote. Her immediate response is to jump up and attack Bodhi! Poor Bodhi, who’s normally asleep at the time, never fights back and there’s never any actual damage. Although Sierra is all bluster, and the redirected defensive reaction to being startled is understandable, it’s still disturbing. She’ll do the same thing indoors or out if she and Bodhi happen to be standing close to each other when something startles her. Because it happens so infrequently and is so instinctive, and because there’s no way to completely control every environment, we manage the situation by body blocking Sierra when necessary and minimizing known triggers.

In the case of dogs who startle awake and snap at their owners who have petted or kissed them, one solution is to wake the dog before approaching by clapping hands, stamping feet, or calling the dog’s name. Behavior modification could be attempted, with the goal of the dog becoming conditioned that being awakened is a good thing. (Here’s a step by step protocol from the Dogtime website.) The success of this type of conditioning will vary from dog to dog. I do still find Sierra’s behavior of running at things that startle her or redirecting her take-the-offense reaction very interesting. Do any of you have a dog who displays this kind of behavior? What have you done to manage or work with it? I’m curious to hear!
Subscribe above to be notified of new postings. You can find my books, seminar DVDs, and blog at And you can find me on Facebook and Twitter.


11 Responses to Startle…and Attack?

  1. Margaret Moran says:

    I volunteer homing rescuerd greyhounds who come directly from having spent all their lives in kennels to life in a home with people around them 24/7. Sleep startle is one thing that we warn new adopters about (especially if they’ve never had a greyhound before) and talk them through what they need to do. With most greys, it’s just a matter of time for them to realise and get used that their humans are likely to disturb their sleep and the startle reaction usually fades with time.

  2. Puppylover8 says:

    So, someone around here was setting off fireworks on Christmas eve. New Year’s eve, fourth of July, ok, I can see those occasions for fireworks and we prepare for them. My dog startled, flew off the bed and injured herself, from the noise at midnight. I am still trying to find out who did this so I can send them the vet bill. What is wrong w/this picture?

  3. Rosee Riggs Good Dog Practice says:

    I am a great believer in letting dogs sleep undisturbed. Dogs new to a home, particularly if they had a stressful past, need that really deep sleep to recover and process things. We all do really. I can’t remember the last time I had to wake a sleeping dog, if ever, so I would never train it which just means doing it repeatedly at intervals and causing more stress. If I had to wake a dog, I would move around or make gentle noises, waking them gently, as you would a child. Instead, I see to it that dogs always have a quiet, safe place to go – whether that is their bed or the sofa or other space – and that is theirs to sleep in peace and quiet. I know someone whose dogs choose to sleep in the garden shed in the summer and upstairs in winter, while she works in her children’s daycare in the sitting room. She calls the shed their sanctuary and no-one is allowed to disturb them. When I have a new client, I always teach them to give their dogs masses of undisturbed sleep and a place where they feel safe and secure.

    • wildewmn says:

      Hi Rosee, I completely agree that it would be best never to disturb sleeping dogs. Where the desensitization would come in for me is in homes where families have small children who are likely to do it anyway, and it can’t be managed to where anytime the dog falls asleep he’s in a crate or otherwise managed.

  4. martie13 says:

    I had Jalen for 14 years, a chow/pit mix, who bit me on the chin when i impulsively kissed her on her head when she was sleeping. I had had her since she was a puppy and she was probably middle-aged when this happened and she’d never shown any aggressive behaviors (with one exception – see below) prior to this. It was totally my fault for startling her when she was sleeping and I learned never to do anything like this again. Live and learn.

    She obviously was a good watch dog/protector. One instance proved this. We had recently moved into a new house and I had a large gravel pile out front that was to be spread on my driveway. One day I saw some kids playing on the gravel pile and I opened the door to yell at them to stop and Jalen charged out the door barking and ran towards them. She didn’t get within a couple of feet to them, never appeared to want to attack them physically, but she did accomplish the mission by scaring them away. Being a woman living alone It made me feel very safe to have her in my home.

  5. Donna Baker says:

    My Charlie (rescue boy who spent most of his life in shelters after being abused as a young dog) does not have a startle reflex when sleeping, but does tend to bark and “attack” strange or novel things in his environment. I perceive it as a fear reflex, a reaction to something he hasn’t encountered before and that makes him anxious. When we spent a few days at the beach this fall, he displayed this behavior towards the gentle waves coming into shore the first time he saw them. I found it quite comical, to be honest, and he soon adapted to the sounds and sights of the beach. Not sure if this link will work, but it’s a short video of him barking at the ocean. ;- )

    • Donna Baker says:

      To add to the above, I certainly don’t take Charlie’s fears and anxieties lightly (and we work on them daily), I just thought it was a bit of a David and Goliath moment on his part to think that he could intimidate the ocean with his barking. After that initial reaction, he loved his beach walks …..maybe he thought he had indeed showed the ocean who was boss, lol.

  6. JennyH says:

    it is NOT just dogs that startle from being woken suddenly. I remember (many many years ago) slapping my daughter hard enough to knock her over when she came up and kissed my cheek when I was asleep. No amount of apologising over the next 40 years has yet earned my forgiveness 😦

  7. Katy says:

    My dog Teddy, when we first got him would…um…express when startled. We took him back to the shelter where we got him because he was expressing blood just days after his adoption (they have vet care there as well). They fixed his poor bottom (there was an anal fissure of some sort), but now he doesn’t like his bottom to be touched, though the only way he expresses that is by, well, expressing. It’s gotten better as he has gotten older, but if he goes to a new vet or there is a new vet tech at his regular vet, they are very much warned.

  8. Paula Tattam says:

    My dog has a startle and attack response and like yours, redirects to my other dog or sometimes the cat. I just manage this behaviour as it is rare enough 😁. Strangely though, if I startle him when he is sleepy, there is no reaction. But if anyone else does, then there will be a reaction. I find this very interesting but don’t quite understand it. At first I thought that maybe I only startle him when he is half asleep and aware that it is me. But I have ruled this out with a few tests.

    Love my doggos to death regardless xoxo

    • Jenny Haskins says:

      Dog, like humans (and probably most other mammals) have different states of sleep. I believe that it is being woken from deep sleep that causes this startle response – I fact, the individual is probably still asleep when they react automatically.

%d bloggers like this: