“She’s never done that before, honestly!”

“It happened out of nowhere, no one saw it coming.”

“We’ve never laid a hand on her! Why would she turn on one of us like that?”

These are just a few examples of the typical statements from heartbroken owners who thought their dog couldn’t hurt a fly. The sad truth is, it happens more often than you’d think, but it’s not completely unpredictable, nor is it necessarily a cause for serious alarm. Despite what you may see in the media, it can happen with any dog, of any breed and at any age. If you’re curious, keep reading to learn (potentially) why dogs attack their loving owners, children or family members “out of the blue”.


Table of Contents

Anyone have a translator?

In her brilliant book The Other End of the Leash, Dr. Patricia McConnell, applied animal behaviourist and dog trainer, explores the ways in which natural human behaviours conflict with those of the canine world. In short, we speak different languages with our bodies.

As an example, when we want to show love and affection, we hug. We kiss. We cuddle. When we’re angry, and at the end of our tethers at the sound of a barking dog, we yell, “QUIET!”. Both scenarios make perfect sense in our human minds but have completely different connotations in the world of dogs.

Laying your arm over your dog’s shoulders, as you would a loved one for a couch cuddle or impromptu hug, reads as rude, obnoxious and downright threatening in the eyes of a dog. Similarly, while we think that yelling at a barking dog is the most logical decision, when in actuality it signals to your pet that it’s time to really make some noise! Anyone with more than one canine in the house will be familiar with the doggie symphony – one begins to bark, and the others soon join in. Sometimes you can get the whole neighbourhood barking its head off!

These are two simple examples of intentions lost in translation between our two species. However, it still hasn’t answered the question of why dogs attack. Why would a dog go as far as sinking its teeth into their loving owner, or lashing out at a child ‘out of nowhere’?


When dogs attack may tell us why dogs attack

Undoubtedly, there are many variables at play, and anyone who’s facing human-directed aggression in their home is heavily advised to seek out a qualified and experienced behaviourist or trainer. In addition, if the behaviour is incredibly out of character, it’s well worth taking a trip to the vet to confirm that there isn’t any hidden illness or pain present, causing your pet to feel more short tempered or sensitive.

So what could be going on? Circumstances may differ from owner to owner or household to household but invariably it comes down to this simple reason: the dog feels threatened.

Read that again – you’re not necessarily intentionally threatening your dog, but he or she may feel threatened nonetheless. This comes back to our two species having disparities in how we perceive language and threat displays in the world around us.

To give you an idea, here are some typical scenarios where family dogs attack:

Someone messes with them or their food bowl while they’re eating

Some dogs display ‘resource guarding’ behaviours. This means they perceive certain items (or people) as theirs and feel threatened when they feel that someone is trying to take it away from them. This is not healthy behaviour by any means, but it is not especially uncommon in dogs either.

Someone stands over the dog and pats them on the head

This can be seen as rather threatening body language in the canine world. Many of us do this to our dogs, often without even thinking about it. Truthfully, the vast majority seem to be fine with it, because they have learned through repeated interactions (often from a young age) that we mean no harm. However, not all dogs are comfortable with such an assertive display, especially from strangers.

Hugs are in the same realm. As stated above, we generally show affection and love by hugging, so naturally, we want to show dogs we love them by doing the same to them. Children are particularly keen to show their love the best way they know how. Sadly , this can be very distressing for some dogs and may lead them to bite if they feel that their signals have not been obvious enough.

why dogs attack signs


Being disturbed while they’re sleeping

Some dogs can become highly defensive if they’re disturbed from sleep. Heck, some people are too! In that state you have no idea what’s going on – it could be an intruder trying to kill you in your sleep! We’re not all particularly clearheaded in that state, and neither are some dogs. In addition, many prefer to be left alone when they’re resting, even if they’re still awake.


“But he attacked out of nowhere”

why dogs attack

Both dogs are potentially exhibiting stress. Top: yawning, turning away, ears back. Bottom: turning away, ears back, whale eye, mouth tight

When someone makes the above statement, usually one of two things is happening in the household:


The dog was signalling loud and clear in his own language…

but it was lost in translation. There’s more to dog body language than barks, growls and tucked tails. Going stiff, ears back, lip licking, turning away, whale eye, and stiff tails are just a few of the many signals that dogs exhibit before escalating to a bite. Through no fault of their own,  young children are often especially lacking and unobservant when it comes to reading canine body language and as a result, statistics around the world confirm that children are the most common victims of dog bites.

The dog has been punished in the past for displaying warning behaviours…

like growling, and has learnt to react without them. Remember that punishment is the discouragement of a behaviour either by adding aversives (like jerking on the collar) or taking away something desirable to the dog with the outcome being that the occurrence of the behaviour decreases. It’s easy to see how someone could fall into this trap, but all it does is teach the dog to minimise the behaviour (growling) itself when they’re feeling aggravated, without changing how they feel about what bugged then in the first place. This makes them harder to read and, therefore, less predictable.

As humans, we never want to punish warning behaviours likes growling, because they allow us to better understand what’s going on in the dog’s head. Instead, you’d be better off uncovering the source of the agitation and training or conditioning them to tolerate their triggers.

Otherwise, it’s time to change strategy and avoid putting your dog in situations that push his buttons. Consider purchasing and conditioning your dog to a muzzle for situations that you can’t avoid, to ensure the safety of others.


Final thoughts

In 2016, there were 31 fatal dog attacks in the U.S. In addition, 77% of biting dogs belong to the victim’s family or friends. Understanding basic dog body language and common triggers can be crucial in mitigating that risk.

Pay attention to the dog’s body language. He may be telling you (or someone else) that he is not comfortable in that moment.

If you’d like to learn more about canine body language, and educate yourself on how to behave around dogs and better understand what they’re trying to tell you, The Other End of the Leash can be purchased through Amazon, or at Book Depository with free worldwide shipping. On Talking Terms with Dogs: Calming Signals (Amazon|Book Depository) is another invaluable book on the finer details we miss in dog body language that speaks volumes in their world. We explore the On Talking Terms in greater detail here.

Hopefully, this post has shed some insight and on why dogs attack, even when they’ve come from perfect homes and never seen so much as a raised hand or harsh voice. Of course, there is always more to the issue, such as temperament, prior experiences, illness, genetics and even mood. Sometimes it’s a perfect storm of all of the above, but very rarely is it completely “out of the blue”.



References and recommended reading

  • Weiss HB, Friedman DI, Coben JH. Incidence of dog bite injuries treated in emergency departments, JAMA 1998;279:53
  • McConnell, P. B. (2009). The other end of the leash: Why we do what we do around dogs. New York, NY: Ballantine Books.
  • Rugaas, T. (2006). On talking terms with dogs: Calming signals. Wenatchee, WA: Dogwise Publishing.


Pin It on Pinterest

Share This