When dogs kill — understanding canine aggression

A newborn child was killed by the family's dog, a husky, in Aidrie, Alta., on Wednesday. Such a tragedy leads to questions about why it happened and, of course, how it could have been prevented.

One of the leading experts on the people-pets relationship is Alan Beck, the director of the Centre for the Human-Animal Bond at Purdue University in Indiana. Beck is also the co-author of Between Pets and People and co-editor of the 2011 book, The Health Benefits of Dog Walking for People and Pets.

Beck has 30 years of experience studying the relationship between humans and pets, from his early days looking at animal bite epidemiology while with the New York City Department of Health.

That research found that dog-bite fatalities tend to come in categories, including "a bite gone wrong." In those cases, the dog wasn't attacking anyone but the bite happened to take place in a fatal location.

Another major category of bite fatalities is with large or medium-size dogs that are socially isolated from children.

Often the dogs were raised by people who didn't have kids, or were not properly socialized. "They come across a human target and almost treat it as a prey species because they aren't used to dealing with young people," Beck said.

CBC News spoke to Dr. Beck by phone from his office in West Lafayette, Indiana.

CBC News: How common is it that a dog would attack an infant?

Alan Beck: In the U.S. dogs kill about 20-30 people a year. About half of them are pit bulls. Most of the fatalities tend to be the two extremes, the very old and the very young.

If you look at non-fatal dog bites, yes, they are much more common in children, 6-14 years, because that's when kids and dogs are active. The fatalities tend to be younger, under one or even under two, or a very old person who cannot defend themselves at all.

For a very young person, it even predates childhood activity, so you can't blame it on the victim, although people try. A majority of the fatalities are the younger group.

For non-fatal dog bites, it's kids, then adults in occupational things but they're not fatal bites.

It's hard to imagine how a baby could provoke a dog to attack, so why would this happen?

Alan Beck: If it's an unsocialized dog, or where the dog is not perceiving it as a baby, perhaps it's perceiving it as another dog, even as a prey species.

That's one of the problems with some of the larger working dogs, especially working dogs that aren't socialized with people.

You have a dog which just doesn't have any interaction with children and then sees this toddler moving and tries to pick it up, maybe not even to eat it or kill it, but just tries to pick it up and in the process, because of the difference in size and vulnerability, kills the child.

It would be nice to see the whole history of this husky, [to determine if it is] more socially isolated, if it's the kind of thing which should just be a bite but turned out to be fatal, versus a true attack.

With babies, are there any breeds of dogs to worry about?

Alan Beck: Size is usually one of the risk factors.

Except with pit bulls. It's the only medium-sized or small dog that has very high fatality rates. There it's probably a behavioural difference with the breed itself. There, too, young people are the most common victims.

Once you go beyond a 15-pound dog, the pit bulls, you find it's the Rottweilers, the Akitas, the huskies; which is probably just a matter of their jaw size and body size.

Are there any warning signs that an individual dog may exhibit, that parents should be on watch for?

Alan Beck: That's another reason why the pit bull is interesting. Many, many  people report that they had no idea, in the pit bull's case, that it's aggressive. While we find in other situations, that if you really talk to the people, you find they actually did have warning.

The dog did growl, it was very protective of maybe clothing or food, was maybe involved in less serious bites. Most dogs do show warnings though very often people don't realize what that kind of growling, or that kind of posturing means.

When you do an interview with the family, especially if they were brought here for dog bites or for being aggressive, you find out that if they had really been looking there was some signs and they should have known it before the first bite.

That's common. Not everybody understands all that is going on with animals but most dogs show some signs.

The pit bull or a dog that perceives an infant as a prey species may not show any warning ahead of time. Although if they are a predatory dog, chances are that the family should have known that if they chase rabbits, squirrels or anything else, that dog may make a mistake when looking at an infant, especially if it is new to the family.

We've had a few cases like that, where it was a first child, new to the family and the dog behaved more like a dog than as a pet, which happens.

Given that situation of new parents with a dog and a newborn coming into the house, what would you advise?

Alan Beck: There's a whole literature of what to do, especially if there's a newborn to the family, about introducing the dog; making sure that when the dog and the child are socializing there's someone there; that the dog is socialized.

In other words, that the dog doesn't perceive the newborn as a competitor but as an extension of the family, and that you work together, that you do things together, so that the dog starts sharing those bond behaviours with the child as well as with the mother and father.

There are all kinds of ways of introducing but absolutely under no circumstances, do you ever let a larger dog and an infant have access to each other in any kind of unsupervised way.

You supervise, you keep reinforcing the dog being nice and you share things together, you give the child a treat, you give the dog a treat, and so it all becomes part of a network, because once either a human or a dog is part of a social bond then it is much less likely to attack.