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Dogs Don't Bite Out of the Blue

Dogs let us know when they’re uncomfortable; we just need to listen.

by Ilana Reisner, DVM, PhD, DACVB

It can be devastating to live with a dog that bites, especially if those bites seem unpredictable or random. This behavior is dangerous for people as well as for the dog, who now is at high risk of being rehomed or euthanized because of his behavior.

The concept of provocation is poorly understood by dog owners and guardians, and even in the scientific literature. In one study of children brought to an emergency room for dog bite injuries, for example, the authors reported that “more than half of these attacks were not provoked.” [1] It’s important to note, though, that even unexpected bites rarely (if ever) occur for no reason.

In fact, unless the dog is sick, all bites are provoked by something. A few considerations:

  • The purpose of aggression is to put distance between the aggressor and his target (“I can’t easily get away from you, so you’d better get away from me”). It’s safe to assume, then, that most dog bites of people are based on defending themselves (fear) or are about the resources they care about (food, bed, human).

  • People and dogs don’t speak the same language and neither is perfectly bilingual. This disconnect sometimes results in interactions which people consider to be “friendly” but dogs view as threatening. If your dog is anxious, a visitor bending to tie a shoelace might be seen as a significant threat.

  • Understanding canine body language is helpful, but knowing your own dog’s “dialect” is most important. Be mindful of your dog’s reactions to people, other dogs, and traffic, near and far. We humans are sometimes so caught up in the surrounding environment and our own self-consciousness that we fail to look down to watch our dogs’ eyes, ears, mouth, tail, and posture.

  • Dogs are often uncomfortable when people face them, stare, reach toward or above them, touch the tops of their heads, or loom over them. They don’t like to be cornered. They’re not great fans of being in a room — veterinary office or your own living room — as someone unfamiliar enters.

  • Remember that dogs can quickly change their minds about interactions with people or with other dogs. Those who seem to accept “sitting visitor” might jump and bite “standing visitor." If you’re even a little uncertain about your dog’s reaction, err on the side of caution and keep some distance between him and the person about whom he’s concerned.

A dog who is conflicted, worried or nervous about an interaction may:

  • Yawn.
  • Flick his tongue.
  • Look away or turn his head away and continue to look at the person indirectly with “whale eyes.”
  • Lift a front leg.
  • Lower his head and/or body.
  • Roll onto his back.
  • Urinate.

Unfortunately, without a dog-human dictionary, people are often unaware that a dog is indicating, “I am worried over here. What is it about STOP that you don’t understand?” For an anxious dog, the next step is to up the ante to growling, baring teeth, snapping or biting, “out of the blue."

What can you do to avoid such tension and, most important, prevent bites?

  1. If your dog is uncertain in some situations, be his advocate. Keep him on a secure lead, and offer him reassurances and food to classically counter-condition his anxiety.

  2. If there is a situation in which your dog has growled or snapped, catalogue it and closely manage similar situations the next time around. Watch that body language closely.

  3. Most important, give your dog the gift of distance from those uber-intimate folks, close to you. Better yet, let him chill in a separate space, with a food toy and radio.

Probably the most important message lost in translation from dog to human is that a dog might not want to interact physically (or at all) at a given moment. Luckily, they’re expressive and social animals, willing to tell us quite a lot, if we listen.

Ilana Reisner, DVM, PhD, DACVB


[1] Gandhi RR, Liebman MA, Stafford BL et al. Dog bite injuries in children: a preliminary survey. American Surgeon (1999) 65:863-864.

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