small dog baring its teeth at a human hand

Demystifying Dog Bites

Recently I had the great fortune of attending the 2018 Dog Boarding & Daycare Expo at the Hershey Lodge in Pennsylvania.  In addition to playing host to a number of niche vendors geared towards the dog industry, the expo also offered its guests continuing education opportunities in the form of seminars given by specially curated professionals from the dog care industry.  One of the more popular seminars at the expo was given by Colleen Pelar, a dog trainer with more than 25 years’ experience and the author of a number of books about training (link to her bio here:  Pelar’s talk was entitled “Demystifying Dog Bites: Reducing the Risk by Understanding the Factors”.  I have summarized what I found to be the most poignant points below:

Anxiety and Arousal

Dog bites are always caused by one of two things: anxiety or arousalFor an anxious dog, predictability and routine are of the utmost importance.  A doggie daycare can foster this predictability by encouraging owners of anxious dogs to send the dog to daycare on the same day every week and attempting to ensure the dog follows a standard schedule with minimal deviations. This can take the form of predictable times that the dog will be both indoors and out, as well as attempting to regularly group anxious dogs with other dogs and staff with whom they know and are comfortable.

Unlike anxiety which is never good, arousal, in small doses, is not a bad thing.  Arousal can be fun.  It allows for energy expenditure.  But because it is liked with aggression, it has to be tempered.  Excessive barking should be discouraged.  And dogs whose play activity does not naturally wax and wane should be re-directed periodically.  In a pack setting, forced “time outs” or breaks – interruptions to play – are pivotal.

Both anxiety and arousal in small doses will rarely lead to aggression, but it is important to note that they both  build up over time.   Pelar cited a personal example when explaining this phenomenon wherein a doggie daycare with whom she consults contacted her because a dog that they had been boarding attacked and injured another dog.  Staff members were confounded because the dog that did the attacking (I will call him Fido for brevity), had been coming to daycare once a week for over a year without incident.  They were surprised that the usually happy-go-lucky dog they knew exhibited this sort of aggressive behavior.  When Pelar dug a little deeper, she realized all the signs that this dog was going to bite were there.

As I mentioned previously, Fido normally went to daycare once a week.  He was happy attending once a week.  He was a 5 YO dog and his exercise requirements were not what they were when he was a puppy or adolescent.  On the first day of Fido’s board, he was his usual, happy self.  Nothing new.  On the second day, he was fine in the morning but by the afternoon he chose to separate himself from the rest of the pack.   He did not feel like socializing.  On the third day, Fido seemed to be getting a little cranky.  He was even less interested in interacting with the other dogs and would growl or avoid if any of them attempted to initiate play.  On the fourth day, Fido was clearly unhappy – his hackles were frequently up, and he was growling and showing teeth at most of the dogs that came near him.  The staff members thought this was out of character but given they never had any issues with him in the past, they assumed he would get over his funk and they doubted he would actually harm another dog.  On Fido’s fifth day of boarding, he attacked another dog at the daycare and seriously injured him.

Fido’s anxiety about being boarded, as well as his arousal from being at daycare every day for five straight days, peaked to the point where he could no longer quell his nervous energy and it turned violent.  Fido should have been separated and sat out of daycare by day three.   He was asking to be excused.  When dogs tell us they are uncomfortable we should neither ignore nor punish them for it.   In Fido’s case, separation would not have been a punishment but a welcome reprieve.  The key is knowing the dog and being able to decipher their nonverbal communication clues.



While anxiety/fear and arousal are the emotions that fuel all dog bites, the situations that pre-empt a bite usually revolve around five things as outlined in the acronym SCARF:

Status: There is typically a pack hierarchy in most groups of dogs, although the alpha dominant can fluctuate.  Status also encompasses resources – my turf vs your turf or my toy vs your toy.

Certainty: As mentioned previously, dogs thrive under routine and predictability so when their sense of certainty falters it can lead to anxiety or arousal, both of which can then lead to aggression.

Autonomy: This derives from a dog’s ability to make his own decisions for himself.  If you force a dog to do something he does not want to do — for example, trim his nails– there is a chance that the dog may react by biting.

Relationships: Not to be confused with status, this one hinges upon who a dog knows and feels comfortable with or conversely, who they do not.

Fairness:  Scientific studies have shown that most mammals, including dogs, are born with an innate sense of fairness.  If you doubt this statement than I suggest you watch the experiment conducted by the well-known primatologist Frans de Waal which tests this hypothesis with Capuchin Monkeys.  De Waal designed the experiment to reward two Capuchin Monkeys in adjacent cages for the same simple task; however, one monkey was rewarded with a high value treat – a grape– and the other monkey was rewarded with a low-value treat – a cucumber.  When the monkey receiving the cucumber sees his friend in the cell block over receiving grapes for performing the same task, he becomes irate and begins throwing the cucumbers back at the researchers as well as banging on his cage and screaming.  This experiment has since been replicated using a number of different animals, including dogs, and the results are consistent with that of the Capuchin Monkeys.  Keep this experiment in the back of your mind next time you decide to give two dogs in your pack different value treats or toys.  It’s true that life isn’t always fair.  It’s also true that we’re not the only animals that know that. **



As with humans, dog behavior deteriorates under stress.  Because of this, handlers and daycare attendants need to be clued in to subtle signs of nervous tension in dogs.   While most people know the obvious signs of an anxious or fearful dog – tail tucked, excessive drooling – there are some oft overlooked anxiety markers as well:

  • Shaking: In addition to shaking when wet to dry off, dogs will also shake to “re-set” or attempt to calm their anxiety internally.
  • Lip-licking: This one looks funny, so humans often laugh when they see it, but it is often a sign of stress/anxiety.
  • Yawning: Dogs may yawn when they are tired, but this too can be a stress-marker.  When attempting to interpret a dog’s yawn, ask yourself, is this dog tired (did he just wake up from a nap?) or am I forcing the dog to engage in an activity for which he might not be comfortable?


Adolescent and Young Adult Dogs Are Most Likely to Bite

Did you know that dogs are most likely to bite between the ages of 2 & 5?  Dogs grow into their aggression, so if you notice aggressive behaviors in a puppy, don’t assume they will grow out of it.  In all likelihood, it’s only going to get worse.   At the other end of the spectrum, dogs approaching middle age tend to calm down both physically and emotionally.   If you think about this in human terms, it makes sense.  Young kids may play fight, but you don’t see brawls taking place at a playground full of preschoolers.   Nor do you see many physical altercations between residents at senior living centers.


Kids and Puppies

Kids between the ages of 5 and 9 are bitten more often than any other age group.  Why?  Inappropriate interactions that are typically not being monitored by adults. While no children are employed at our daycare, the frequency with which they are bitten can be used as a helpful metaphor in dealing with puppies.  Puppies are like children in that they will test their boundaries with the older dogs.   Also, like children, they should be monitored to insure they are behaving appropriately toward their elder pack members as even the most patient older dogs will have a breaking point if pushed to an extreme level of annoyance or aggravation.



The good news is that, while dogs do bite, statistically speaking, balloons and slippers are both more dangerous (to both dogs and humans).  And while every dog will have a unique temperament, all dogs will exhibit the same (or similar) patterns of behavior before resorting to aggression.  Pelar also notes that early socialization is hugely important for dog to dog interaction so dogs should not be separated from their litter mates before eight to ten weeks of age.  Doggie daycare can also be hugely beneficial for the development of puppies.

In summary, many things are unpredictable – the stock market, the weather in New England, and American Airlines scheduled departure times – but dog bites shouldn’t be.

*Fun fact: boys are bitten twice as often as girls.

**A video of the experiment referenced above can be viewed here:


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