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I was sitting in front of a coffee shop at a tiny outdoor table, drinking an overpriced cappuccino with two friends. At the table next to us sat two women, one of which had a Chihuahua with a red leather, rhinestone studded, collar. The dog hovered near her feet and paced back and forth to the extent that his leash would allow, acting in an excited and vigilant manner. The pavement next to the coffee shop had the usual collection of pedestrians, however when a young man wandered by with a large, mature, Labrador Retriever, the Chihuahua became frantic — barking and lunging toward the bigger dog. The Lab slowed his pace a bit to look at the tiny, noisy dog, and then resumed his leisurely strolling pace as though nothing particularly interesting had happened. One of my friends leaned over to me and said in a low voice, "Another example of a yappy, frenzied small dog and a calm and reserved bigger one. It seems like it's always the case."
My friend was expressing a commonly believed stereotype which suggests that there are behavioral differences between larger and smaller dogs, with the small dogs being viewed as more excitable and anxious. A number of pieces of research have suggested that there may be some truth in this stereotype. For example one of the more recent studies of this issue appeared in the journal Applied Animal Behaviour Science. The research team was headed by Christine Arhant from the University of Veterinary Medicine Vienna. It was a large ambitious study, involving a survey questionnaire that consisted of 237 questions, and was sent by mail to registered dog owners in Vienna, Austria. The final analysis was based on 1276 completed surveys. Given the mass of data and the complexity of the results I will only be able to touch upon some of the highlights of this research here.
For the purposes of statistical analysis the dogs were divided by size, arbitrarily classifying as big dogs those who were larger than 44 lbs. (20 kg) and as small dogs those who were less than this weight. The first behavioral dimension tested had to do with dog obedience. Owners were asked whether their dog reliably obeys the commands "sit", "down", "heel", and the "come" when off leash. There were also questions that asked if the dog is attentive and not easily distractible, learns commands easily, obeys commands to hand over objects, pulls on the leash and so forth. Overall the researchers' analysis showed that the smaller dogs were significantly less obedient than the larger ones.
The second behavior component that they analyzed was called aggression and excitability. Typical behaviors which they looked at included whether the dog growled, snapped or barked at dogs, or at visitors to the home, or at strangers in the street, or at family members. They also determined whether the dog typically fights with other dogs, barks at or pursues joggers or cyclists, is excitable when the doorbell rings or when other dogs are seen. Other items looked at whether the dog guarded its food or other objects, and a variety of other similar behaviors. Once again the results were unambiguous with the smaller dogs showing more aggression and excitability to a significant degree.
The third behavior component that they looked at was called anxiety and fearfulness. This included owner's ratings of whether their dogs showed behaviors such as, anxiety in unknown situations, fearfulness when exposed to loud noises like traffic or fireworks, is afraid of unknown humans, dogs, or crowds, seems restless and unable to relax, or frequently shows various body signs of anxiety such as lowered body posture, panting, salivation and trembling. Once again there was a significant difference based upon the size of the dogs, with the smaller dogs being significantly more fearful and anxious.
These results seem to confirm the stereotypes about small dogs, namely that they are less obedient, more excitable and aggressive, and more prone to anxiety and fearfulness. Are these differences due to genetic factors or to the way that small dogs are treated in comparison with large dogs? This Austrian group of researchers had the suspicion that some of the behavioral differences between the smaller and larger dogs are related to the owner's behaviors and interactions with the dogs and analysis of their data seemed to confirm this.
The first important factor that they discovered has to do with the owner's consistency when interacting with or training their dog. Examples of inconsistent behaviors include not always giving commands in the same way, not maintaining fixed rules for the dog (for example sometimes punishing a dog for a particular behavior and other times allowing that behavior), or not responding to a specific misbehavior in the same way each time. The data from this study shows that the more consistent the owner's behaviors are the better the dogs' obedience behaviors are regardless of their size. However, support for the researchers' suspicions that the owners' behaviors were important came from the fact that the data also shows that owners of small dogs are more inconsistent in their interactions with their dogs than owners of large dogs. This problem is compounded since it appears that inconsistency has a larger negative impact on smaller dogs.
Another finding has to do with shared activities between the dog and owner. These include formal activities like obedience training or agility work, but also informal activities like playing fetch or jogging with the dog. The data shows that the more engaged that the owner and dog are in such activities the more obedient the dog appears to be. Once again we find a difference in the behaviors of dog owners, with the owners of small dogs spending significantly less time in shared activities with their pets.
One particularly important finding has to do with the specific techniques that owners use when training their dogs were trying to control their behavior. A number of studies have shown that the use of punishment has negative effects on the dog's training success and on emotionally-based responses such as anxiety and aggression (click here or click here for some examples). This was verified in this current study where the use of punishment in the form of leash jerks, hitting, scolding, grabbing the dog by the scruff of the neck and shaking and so forth resulted in more disobedience for the dogs. Regardless of their size, dogs that were punished more frequently showed more aggression, however the effect was greater in smaller dogs. Another major difference between smaller and larger dogs concerns the relationship of punishment to anxious and fearful behaviors. The researchers found a positive correlation between the frequency of punishment and the anxious and fearful behavior scores of the dogs — but in this case this relationship was only significant for the smaller dogs.
Based on their research these investigators derived certain recommendations for owners of smaller dogs, specifically, "We conclude that smaller dog owners could significantly improve obedience in their dogs by being more consistent in interactions and engaging regularly in play and training activities with them. Behavioral problems could be reduced by avoiding habits of punishment that might reinforce fear or fear-related aggression."
These recommendations might have been a value to the owner of the Chihuahua that day, since her response to her dog's noisy lunging at the Labrador Retriever was to jerk at the leash and to scold the dog with a loud "Stop that!" Definitely not recommended owner behavior according to this research.
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: Christine Arhant, Hermann Bubna-Littitz, Angela Bartels Andreas Futschik and Josef Troxler (2010). Behaviour of smaller and larger dogs: effects of training methods, inconsistency of owner behavior and level of engagement and activities with the dog. Applied Animal Behaviour Science, 123, 131-142
