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Dogs Don't Bite Out of the Blue

Adrienne is a certified dog trainer, former veterinary assistant, and author of the online dog training course "Brain Training for Dogs."


Dogs don't bite out of the blue, they climb a ladder of aggression that escalates if no measures are taken. How many times have you heard about dogs who have turned on their owners, dogs who have a Dr. Jekyll and Mr Hyde personality, dogs who bite out of the blue? Well, it may seem so to the untrained eye, but to those who can read dogs well, dogs tell a whole different story and Dr. Kendal Shepherd is sure one of them. A veterinary surgeon from Bristol University and a certified Clinical Animal Behaviourist by the Association for the Study of Animal Behaviour, Dr. Kendal Shepherd sure knows her way around dogs. It is thanks to her simple illustration on the Ladder of Dog Aggression that nowadays many trainers and behavior consultants can explain to their clients how the behavior that "came from nowhere" was actually preceded by many signs. I always keep an illustration handy for my clients and will be happy to post a link to the illustration for those interested in learning more about dog body language.

Why is learning more about the Ladder of Aggression so helpful? Fact is, dogs are constantly communicating to us their emotions. If you own a dog, your dog likely goes through a vast range of emotions on a daily basis. He can be happy, frustrated, bored, excited, lonely, relaxed and so much more in just a 24 hour day. It's up to us as the owners to "listen" to what our dogs are saying, because when it comes to aggression, dogs try to communicate their growing discomfort before going to a straight bite. There are sometimes exceptions to this and I have mostly seen this happen in dogs suffering from a medical problem or dogs who have been punished for exhibiting ritualistic aggressive displays.

In the case of dogs suffering from medical problems, the reaction is often reflexive as the dog is often startled. Just as we would pronounce a startling "ouch!" when hurt, dogs may just turn around and bite. Veterinary professionals are aware of this reaction and this is why they often muzzle dogs. When you bring your dog to the vet and your dog is in pain, it doesn't matter that he has never bitten anybody before and that he doesn't have a "mean bone in his body." Pain causes dogs to react in uncharacteristic ways. I always recommend dog owners to train their dogs to wear a muzzle to protect veterinary staff just in case. Muzzling your dog is not saying "my dogs are mean" it's simply saying "I am being responsible." My dogs are always muzzled when they see the vet especially if it's for a painful condition or the diagnostic tests can cause discomfort.

In the case of dogs being punished for displaying ritualistic aggression, this is sadly quite common. It's almost instinctive for dog owners to want to punish a dog from growling, especially if the growl is directed towards a child. It's unfortunate though that this leads to more problems down the road which may lead to what you were actually hoping to avoid in the first place: a bite. Fact is, we need dogs to communicate to us. Communication is how dogs are given the opportunity to avoid conflicts. If a dog is growling because a child is hugging the dog, we want the dog to let us know that he's feeling uncomfortable, because the day you start punishing your dog for growling, next time the child hugs the dog (which really shouldn't), your dog may seem to you like he's tolerating it, but after some time since you have suppressed the growl, the dog may end up biting with no warning. Suppressing a growl is like creating a ticking time bomb, but this time there won't be any ticking sounds! I always cherish the words of one of my favorite dog trainers, Pat Miller. She states in her article: The Gift of Growl: " a growl is something to be greatly treasured." And boy is she right!

Another scenario that may sometimes cause a dog to skip giving out a few early signs may take place when a dog is exposed to a threatening situation that happens too quickly or is too intense or too close for comfort. This is why when working on cases of aggression, you want to expose dogs gradually and systematically to their triggers without overwhelming them which ultimately puts them up for failure.

Therefore, learning more about the ladder of aggression is helpful to both novice and seasoned dog owners. It's a reminder about how important it is to be in tune with our dogs so we can better understand them, one rung at a time, and most of all, without missing any steps so behaviors won't fall apart!

The Ladder of Aggression

As mentioned, the Ladder of Aggression is an illustration by Dr. Kendall Shepherd. The illustration depicts the different escalation phases in ascending order dogs go through when they are feeling stressed or threatened. Just as when climbing a ladder, the signals shown on the lower rungs of the ladder, include mostly appeasement signals such as yawning, lip licking, turning the head away or pawing. In dog language the dog is trying to say something in the means of meaning “I am starting to feel uncomfortable, please calm down”. As things progress, there may be more and more signs of discomfort where the dog may appear to be almost pleading " I am getting more irritated, please, don't make me escalate."

On the top of the rungs instead are signals that grow more and more in intensity. These signals are the most evident signs of aggression, the ones that are unmistakably recognized even by the untrained eye. In dog language, these dogs are likely saying something like " Those on the higher rungs of the ladder, such as growling, snapping and biting mean “I have had enough, leave me alone right now!”

While these signals are meant to communicate with us, problems start when we fail to take notice of these signals. From the dog's perspective, we are ignoring his effort to maintain peace and avoid conflict, which makes him more likely to escalate to something you may understand better such as growling or snapping. Dr. Kendal Shepherd cares to precise in her article on Keeping Ourselves Safe Around Dogs that : "It must be stressed that aggression is not, however, a routine means of communication – it is a last resort if all else fails. She adds: "If a dog bites a person, it must mean that, at that moment, communication between the two individuals had failed to such a degree that aggression became the only option as far as the dog was concerned.To prevent dog bites, it is essential to realise that all dogs want to avoid aggression if at all possible."

For those interested in viewing the Illustration by Dr. Shepherd click here: Ladder of Aggression by Kendal Shepherd, in BSAVA Manual of Canine and Feline Behavioural Medicine, © BSAVA 2002.

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Disclaimer: this article is not meant to be used as a substitute for professional behavioral advise. If your dog is acting aggressive, please consult with a behavior professional for proper assessment.

Alexadry, all rights reserved, do not copy.

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Adrienne Farricelli (author) on September 28, 2015:

Thanks Ladyguitarpicker, my male dog is very vocal and in a few instances he has let me know when something I do is bothering him. Like once he told me he wasn't comfortable with me brushing a particular tooth (turned out if was infected) and when he was a pup he once got tired of me repeatedly trying on an Elizabethan collar to get the right fit. Poor boy! I see it as a kid saying "mom, I have had enough, please give me a break OK?" I haven't heard him growl now for quite some time, but I really appreciate him telling me when something I am doing he's not much comfortable about.Making me aware of it, makes me more attentive in being less intrusive in the future and taking steps in making the activity more pleasant.

Adrienne Farricelli (author) on September 28, 2015:

Lambservant, it's hard to say why this dog may be doing this without seeing the behavior . It could be due to fear, herding instinct, territoriality or even play. The chances of biting are based on the dog's level of bite inhibition and one must consider that high arousal levels can cause a dog to escalate to real biting. I never trust when my clients say: "never really bites." Any dog can bite given the right circumstances or escalate to biting. I would say, go with your comfort level. I sometimes stumble on dogs with serious behavior problems and bite histories and have followed my gut instinct and referred them to a veterinary behaviorist to play it safe.

stella vadakin from 3460NW 50 St Bell, Fl32619 on September 27, 2015:

Wonderful hub and full of good information. I never could understand why people think their kids should be able to hang on dogs. I have never heard my dogs growl, just one when she sleeps.

Lori Colbo from United States on September 27, 2015:

I have been doing a lot of dog sitting and am learning a lot about canine behavior. Someone called me seeking my services yesterday and he shared that with one of his rescue dogs "nips" at your heels when you turn your back on him, but he never really bites. Famous last words. Why do dogs do this and does it indicate they can really attack and bite hard under certain circumstances when ones back is turned? Should I consider not sitting this dog? Owners forget or don't consider the stress some dogs are under with them gone and a stranger watching them.

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