Physicians are always complaining that whenever they are at a casual social event or meeting, people often approach them for advice about treating or diagnosing their various physical ailments. Those of us who study dog behavior often have similar experiences in that people use any social gathering or meeting as an opportunity to seek advice or understanding about the latest problem or quirk being demonstrated by their pet dog. For me the latest example of this occurred at a reception which was associated with a psychological conference in Ottawa, Canada. A military psychologist, who I had met a few years earlier, came up to me to seek some advice about his Labrador Retriever, Major.
He explained, "Recently Major has started to engage in inappropriate chewing. He seems to like leather, and my wife caught him chewing on the strap of her purse, and then some time later he shifted to chewing on her shoes. Every time she catches him in the act she yells at him. Occasionally she will grab the nearest magazine or newspaper which she rolls up and swats the dog with — all the time she is shouting 'Bad dog! Bad! Bad!' Major acts guilty, as if he understands that he's done something wrong, but within a day or sometimes even just a few hours he's back at it again."
I tried to explain to him that I doubted that the method his wife was using was going to change the dog's behavior. I then suggested a much simpler way, "When you catch the dog engaging in any inappropriate chewing, simply make a trade. Take the object away from him and give him something more desirable — and acceptable — to chew."
He looked at me very skeptically and commented, "I thought about that, but somehow it seems to me that giving him something desirable in that situation is tantamount to rewarding him for bad behavior. This is certainly one of those situations where the dog is doing something wrong and should be punished. Certainly if the punishment is appropriate it should stop the behavior."
I pointed out to him that one of the ongoing controversies among dog behaviorists and dog trainers has to do with the effectiveness of rewards versus punishments. Most of the data that I had seen so far, generally shows that punishment is not a particularly effective training or behavior modification tool when you are dealing with dogs (click here, or here, or here for some examples). As I was speaking to my colleague I remembered that I had previously encountered one study that specifically addressed the best way to deal with problem chewing behavior. So I told him that when I returned home after the conference I would look for that research report and send him a copy. It took a little bit more digging than I expected, since the article was published a decade ago, and the information that I was looking for was just one of many comparisons in a larger investigation. The study was headed by E.F. Hiby who was in the Department of Clinical Veterinary Science, at the University of Bristol and it was published in the journal Animal Welfare*. The purpose of this research was to see how effective typical dog owners found reward-based or punishment-based techniques to be when training their own pets.
The investigators distributed questionnaires to 364 dog owners living in Hampshire and Cambridgeshire England. Most of these dog owners were approached while they were out walking their dogs. The questionnaire asked them to describe the specific methods that they used to train their dog to do some basic tasks, such as coming when called, sitting on command, to leave or give up an object, and to walk at heel. It also asked how they tried to control certain problem behaviors such as chewing household objects or stealing food or other things. It turns out that these typical dog owners used a variety of different combinations of rewards and punishments in their attempts to train their dogs. The data showed that 66% of the dog owners reported using vocal punishment (loud forceful voice or yelling), 12% used physical punishment (hitting the dog, jerking the leash), 60% used praise as a reward, 51% used food rewards and 11% used play as a reward. To see how effective these methods were the researchers got the dog owners to rate how obedient the dog was after training for each task. Basically what they found is that the more tasks that were trained using rewards the better the dogs overall obedience performance was.
When it comes to punishment the authors conclude that "Although the most effective technique varied according to the specific training task, for none of the tasks was a punishment-based method most effective." However, punishment, although not being particularly effective in training the dog, did have an effect — although not one which most people would find favorable. When asked whether their dogs exhibited any of 16 common problematic behaviors (the list included several varieties of aggressive behaviors, fearfulness, over excitement, separation distress, among others), it was found that the number of problems that the dogs showed was directly related to the number of tasks for which the dog was trained using punishment.
Taken as a whole the results of this study seem to confirm other reports in the scientific literature which show that reward-based training is more effective than punishment-based training and that punishment may well trigger problematic behaviors in dogs. However up to now we have been talking about the overall results of this study averaged over a variety of tasks. I am sure that an astute reader would still be left wondering what this has to do with my colleague's difficulties with a dog that chews objects that he shouldn't. It so happens that the authors actually singled out that particular situation for comment saying, "Even for chewing and stealing objects, where punishment is very commonly used, those owners who used it did not report greater obedience." But they go on to suggest a remedy which works, "Obedience for not chewing household objects was greater in those dogs that had received an alternative object to chew in response to their chewing behavior, in comparison with those dogs that had not received an alternative." So although the focus of this study was much wider, we are left with a practical suggestion for remedying one common problem behavior in dogs. I did send a copy of the research report to my colleague, as promised, but also suggested that keeping shoes in a closed closet, and not leaving handbags on the floor might be a helpful strategy in this case.
Stanley Coren is the author of many books including: The Wisdom of Dogs; Do Dogs Dream? Born to Bark; The Modern Dog; Why Do Dogs Have Wet Noses? The Pawprints of History; How Dogs Think; How To Speak Dog; Why We Love the Dogs We Do; What Do Dogs Know? The Intelligence of Dogs; Why Does My Dog Act That Way? Understanding Dogs for Dummies; Sleep Thieves; The Left-hander Syndrome
Copyright SC Psychological Enterprises Ltd. May not be reprinted or reposted without permission
Data from: EF Hiby, NJ Rooney and JWS Bradshaw (2004). Dog training methods: their use, effectiveness and interaction with behavior and welfare. Animal Welfare, 13, 63-69