Why Do Dogs Bite?

Dogs bite as a last resort when their boundaries are not respected, they feel threatened, or they are afraid. According to the CDC, 4.5 million people are bitten by dogs in the United States each year. Over 50% of dog bite victims are children, and most people are bitten by their own pet or a dog they know.

Once a dog has bitten, she is more likely to bite again because she has learned it works for her and stops the unwanted interaction. So, dog guardians need to take preventative measures to reduce the likelihood of a bite. You can start by educating those around you to treat your pet with respect.

You Can Prevent Dog Bites

Preventing bites starts with understanding your dog’s needs and learning to listen to what they are telling you. Review Dog Communication to learn more about dog body language and communication.

Every dog has his own level of tolerance for different stimuli which causes him to react in many ways, from discomfort to biting. Just as some people are quick to anger whereas others remain calm when upset, dogs are the same way! They have different personalities and different things that can “set them off.” As responsible pet guardians we have to learn our dog’s triggers, educate others, and take preventative action to keep our dogs and others safe.

woman posing wit two dogs outdoors

The Tolerance Threshold

Below is a general emotional scale of the different ways a dog can feel in response to certain stimuli such as other dogs, strangers, being touched, or children. On this scale, the dog’s feelings towards stimuli are equally distributed.

A spectrum of happy to angry

However, each dog’s tolerance threshold is different. Some dogs have very little green, or tolerance to stimuli, and have more orange and red. This means they are quicker to react negatively to a stimulus and possibly bite.

A spectrum of happy to angry, with greater areas of angry

Some dogs have more green, or a higher tolerance, and take longer to react negatively. More green does not mean that they will not react negatively, but it will just take longer for them to become angry. So they are “more tolerant.” 

A spectrum of happy to angry, with greater areas of happy

But, each dog has a different tolerance threshold for different kinds of stimuli. Your pet may be tolerant to some stimuli, but not all. For example, a dog that is tolerant with other dogs may be intolerant with children. 

How do we know where our own dog’s threshold levels are? By watching and learning. In Dog Communication you learned that dogs communicate with body language. Pay attention to those messages. If your dog lip licks and whale eyes every time a stranger approaches her, she is uncomfortable with strangers. With more observation you could learn she is head shy, because she is only nervous when strangers pet her head. Notice how long your dog lets a stranger pet her head before reacting, and how she reacts.

The Ladder of Aggression

This brings us to the ladder of aggression model, which shows the behavioral steps dogs will take before they bite. The signals discussed in Dog Communication 101 are listed low on the ladder in green. Some dogs will follow the steps of the ladder and show each warning signal before biting, but some dogs may not display every step, like the ladder on the right.

A dog’s tolerance threshold for a stimulus that is causing stress, fear, or nervousness determines how he may react to that stimulus. Understand the ladder of aggression model, but be aware most dogs won’t show all of the signs on the ladder in chronological order. The graphic on the right shows a dog’s ladder of aggression that skips several steps before resulting in biting. That is why it is so important as responsible pet guardians that we pay attention and respect the first signs of stress, unease, or fear in a dog before it’s too late.

A ladder of aggression showing dog reactions, from walking away to biting
A ladder of aggression model with missing ladder rungs

Not Your Dog

We started with education on how to better understand our own dogs in order to learn how to better recognize these same emotions in a dog that is not ours. Other dogs do not know you like your own pet does, so their threshold of tolerance for you or another stranger is immediately lower. We must always respect a dog’s boundaries, especially when they are not ours.

Children and Dog Bites

First and foremost, younger children (newborn to 10 years old) should never be left alone unsupervised with a dog. Even if that dog is your own family pet, too many things could happen. It is very important to educate our children how to interact with a dog properly, safely, and humanely. The child pictured to the right is not.

Children are the most common victims of dog bites. This is because children can be very scary to pets when they move quickly and unpredictably, scream loudly in play, or touch the dog roughly or in a way that makes the dog uncomfortable. Imagine being a dog and not understanding why a tiny human is doing all these things. Too many people see this as harmless play or affection. But we need to learn to recognize whether our dog is actually enjoying the play.

Children who are bitten by dogs are often bitten in the face, because their face is so close to the dog’s face during interactions.  As humans we show affection to one another using hugs and kisses. Dogs, however, do not. To them, a hug is a form of restraint and a kiss is invasive, and these actions can make them uncomfortable. So, even though we are just trying to give them love and affection like we would any other family member, these actions are interpreted differently by a dog. The photo to the right is one we often see on social media, and yes it is cute, but photos like this are often taken moments before a dog bites.

graphic showing canine bite levels one through six

Prevent Bites with Socialization and Training

The critical socialization period for dogs is between 3 and 12 weeks of age. This is the time to carefully introduce a puppy to lots of different stimuli to increase their confidence and get them used to different people, other animals, children, noises, cars, new places, and more. The hope is they will build a higher tolerance to stimuli as they have been safely and gently exposed to them during the critical socialization period. Learn more about socializing your puppy here.  

Dogs who are not socialized as puppies can become afraid of things that they were not exposed to during that time. Many of us did not have our dog during this critical socialization period, but we can still help them gain confidence around new things. Positive counterconditioning is a form of training that can help your dog learn that something they see as “negative” or “scary” is not so scary because it predicts good things. For example, if your dog is scared of cars, give your dog yummy treats every time she sees a passing car.

Preventing your dog from biting is important for not only the safety of the humans interacting with your dog, but for your dog himself. Accidents do happen, but we encourage you to follow this advice the best you can, and protect you and your dog from the consequences of a bite.


Written by Nayla Garcia

Dog Communication 101

Need a refresher? Review this page to learn about dog body language and better understand how to prevent dog bites!

Learn more!

Test Your Knowledge!

Can you prevent dog bites? Put what you’ve learned to practice and see if you can spot the dog’s warning signs in “What’s Wrong with This Picture?”

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