Training Aggressive Dogs

Punishment-based training is inappropriate yet the dominance theory persists

November 3, 2014 (published)


The most common reason a dog is surrendered to a shelter is bad behavior, and aggression to people and/or other pets is pretty high up on that list of bad behaviors. Most dogs euthanized in a shelter for bad behavior are less than a year old.

Sad, isn't it? In many cases, these dogs weren't trained well or were not trained at all.

What can we do to change this? After all, we don't want to see dogs dumped at the shelter or euthanized for bad behavior. Studies tell us that training dogs results in dogs with fewer behavior problems, and thus less chance of ending up in a shelter. We've also learned that using positive reinforcement is, by far, a much, much better method of training. Thanks to that positive reinforcement, we see better obedience and fewer bad behaviors.

Veterinary behaviorists such as Sophia Yin and trainers such as Karen Pryor have developed training methods using positive reinforcement with great results and far fewer injuries to trainers, owners and the dogs themselves. In contrast, trainers such as Cesar Milan, who teach aggressive dogs to submit to a person using dominance rolls, are practicing an extremely outdated method. Using dominance rolls today is kind of like wearing those huge shoulder pads from the 80s or go-go boots from the 60s: they may have been popular in their time, but today they're just part of Halloween costumes.

It turns out that practicing dominance over a dog, a punishment technique, has resulted in trainers and owners being bitten, as well as dogs getting hurt both during and after training sessions. That's not likely what you had in mind when all you wanted was a dog who behaves well.

Over the past 25 years - yes, a quarter century! - both veterinary and non-veterinary behaviorists have said that punishment based-techniques are not appropriate, especially for aggressive dogs, yet the dominance theory persists. Usually aggressive dogs are anxious and fearful, and this type of training actually makes them worse, not better.

Why did we think it was useful? Sadly, this theory of dominance training was misinterpreted from a study on wolves. The truth is the polar opposite of the myth: in the wild, subordinate wolves show deference to dominant wolves by rolling onto their backs, unasked. They choose to roll over, they are not asked to do so. Dominant wolves never force subordinate wolves onto their backs. Using this tactic on a dog makes no sense from a training point of view, plus it is dangerous to the bewildered dog; he only learns that people can be terrifying (getting rolled reinforces his view) and the owner can get bitten.

That dominance roll is the most dangerous canine behavior myth, according to behaviorist Valarie V. Tynes, DVM, DACVB, in her 2008 peer-reviewed paper "Behavior Myths" (peer reviewed means that lots of other scientists agree). A dominance roll is trying to show an aggressive dog who is boss by rolling the dog on his back to discipline him and remind him the human is the leader of the pack. Sometimes yelling accompanies the roll. The human certainly should be the leader, but these dogs should be trained using a type of positive reinforcement called the "no-free-lunch" or "learn-to-earn" method that teaches the dog that the owner is trustworthy, predictable, and not likely to fly into anger.

Our emotions and actions, including those based in anger, drastically impact our dog's world.

I imagine myself as a dog, dropped into a foreign country where I don't speak the language. If someone is trying to get me to cross the street and their body language and tone of voice is kind, I am more likely to listen and follow them, even if I can’t understand what they're telling me. If someone is yelling and screaming at me, trying to grab my arm and haul me across the street, I'm not going to want to go. I'm going to pull away so I can run away; I may even kick and hit at the person. I'm sure that is how a lot of our dogs feel when we're trying to train them, especially with punishment-based training. No wonder they try to flee or bite when we treat them this way - I would too!

So what should we be doing to train fearful or aggressive dogs? Use kindness, which we call positive reinforcement. Didn't grandma always say that you can catch more flies with honey than vinegar?

Clicker training is one form of positive reinforcement that can be used to train dogs - actually most any animal. It's fun for the dog and fun for the owner, and anything that's fun is more likely to be done consistently. Consistency is important in all training, be it dogs, cats, horses, or toddlers. Can you imagine how a toddler feels when someone is yelling and screaming at him all the way through toilet training? Don't kid yourself: That would come in up therapy.

No veterinary behaviorist, or member of the American College of Veterinary Behaviorists, would recommend dominance-based training today. If you are looking for a trainer, first ask what methods are used. If they rely on a pinch collar rather than a head collar, if they insist you show dominance, if they teach you to snap the leash to get your dog’s attention, keep looking. If they believe that the dog will learn better without you around, think again. After all, not all training is taking part on the dog’s end of the leash: dog training is as much about training the owner to handle the dog as it is about training the dog.

Tynes says, in her 2008 paper, that "appropriate training for a dominant dog requires teaching the dog that the owner is the leader and involves being calm, consistent, and trustworthy." She recommends some version of learn-to-earn or no-free-lunch training, in which the dog is asked to respond to a command such as "sit" or "shake" for every resource the dog wants, including meals, walks, and play. The worst thing that can happen to a dog in this method is that he doesn't get what he wants. (Be still, my bleeding heart.) This method teaches the dog to defer to his owner.

The only time a dog should be on his back is when it's his idea; after all, belly rubs strengthen the human-animal bond. But when it comes to shaping behavior, steer clear of any trainer who believes that dominance is the answer to your dog’s aggression unless your goal is to make him more fearful and more aggressive - or if you like being bitten.

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