In writing a summary of dog park law, Fran Breitkopf and I noted that dog park sociology would inevitably become a topic for scientific journals. We were thinking about what dog parks mean for people, rather than dogs, but four Canadian researchers (Ottenheimer Carrier et al., citation below) have published a study suggesting that dog parks may be very entertaining places for dogs that score high on Extraversion in personality tests, while probably being threatening and uncomfortable for dogs that score high on Neuroticism.
Cortisol, hydrocortisone, is a steroid hormone produced in the hypothalamic-pituitary-adrenal axis in response to stress and other stimuli. It increases blood sugar through gluconeogenesis and aids in fat, protein, and carbohydrate metabolism. It has been studied in baboons, monkeys, dogs, horses, and birds, though a recent paper notes that the relationships between cortisol, social behaviors, and personality traits have rarely been studied in non-human animals. There have been some cortisol studies of dogs in kennel settings, as well as work situations for trained dogs, including service, therapy, and police dogs, but companion animals have generally been ignored.
Canine Personalities
In an attempt to determine why cortisol levels might increase more in some dogs than others during visits to dog parks, the authors of this study looked for correlations that might occur based on a dog’s personality. Studies of dog personality have often focused on “coping styles.” Quoting Horváth et al., a study of police dogs (cite below), they note:
“[P]olice dogs characterized behaviourally as having an ambivalent coping style showed more signs of acute stress (e.g., low body posture, snout-licking, and paw-lifting) and demonstrated a cortisol surge in response to a threatening stimulus.”
Other assessments of personality are based on analysis of personality traits, such as exploration, boldness, fearfulness, and aggression. For their dog park study, the Canadian researchers chose a personality assessment called the Monash Canine Personality Questionnaire-Revised (MCPQ-R), which uses a rating scale for 26 traits clustered into five personality dimensions:
- Extraversion
- Motivation
- Training Focus
- Amicability
- Neuroticism
Motivation and Training Focus are perhaps unique to domestic dogs in terms of personality measurement. The researchers sought to determine relationships between cortisol, personality, and specific behaviors and postural changes indicative of play, agonism (conflict behavior), and stress, of dogs interacting in dog parks.
Study 1
Study 2
The second part of the research involved 60 companion dogs ranging from 6 months to 15.5 years, 34 of which were purebred and 26 mixed, also recruited from the Quidi Vidi Dog Park. Dogs had been owned an average of two and a half years and 81% were spayed or neutered. Most dogs visited the park more than three times a month. Since the dog park is recommended for dogs weighing more than 12 kg (26.5 lbs), most dogs were medium to large in size.
Owners were recruited by researchers who had set up video equipment and asked if they would consent to having their dogs videotaped. A consent form was provided, and basic information about the dog and the household was obtained. Owners completed the MCPQ-R as a means of assessing a dog’s personality. In other words, the personality assessments in the study were not made by the researchers, but by the owners of the dogs. After a play session, a sample of the dog’s saliva was taken with a swab.
Categories of Behavioral Activities
The behaviors documented by the research team from the videotapes were divided into four broad categories: (1) play/attention, (2) agonism, (3) stress, and (4) mounting. Each of these broad categories except mounting had a number of possible manifestations, as described in the following table:
Behavior | Description |
Play/attention | |
Exaggerated approach | Slow, running approach in sightline of partner; loose, rolling nature to run. |
Exaggerated retreat | Backwards leap; head up towards partner. |
Play bow | Forelimbs down; hind legs raised; tail erect or wagging. |
Chase-me | Withdraw with looks backward; at a reduced pace or with loping stride; new instance of behaviour when it persisted for 5 seconds. |
Open-mouth | Frontal display with teeth and lips showing; no biting. |
Bow head | Nod head below shoulder level; maintain or nod up. |
Play slap | Usually simultaneous slap of ground with two forelimbs, occurs in play bow position. |
Leap-on | On hind legs, with front paws around partner’s head; tail up. |
Bump | Use part of body to knock into partner. |
Nose | Put nose and closed mouth to other; non-investigatory. |
Bite | Make firm mouth contact (of scruff, rum, face, or body); force is tempered |
Bite-at | Can have no clear object; biting at air in the direction of, but not touching, partner; can be partial or repeated. |
Paw | Paw at other’s face or body. |
Agonism | |
Growl | A low frequency but audible rumbling produced in the throat. |
Bare teeth | Lips curled upward, possible exposure of teeth. |
Snap | Sudden biting motion in direction of a conspecific. |
Bite | Firm mouth contact where mouth and teeth have firm grip on conspecific. |
Lunge | Sudden angular leap towards conspecific. |
Chase | Driving away conspecific. |
Stress | |
Tucked tail | Tail positioned between the back legs; new instance when tail remained tucked for 5 seconds. |
Hunched posture | Back curved upward, body and head lower to the ground; new instance when back stayed curved for 5 seconds. |
Paw lift | One front paw is lifted off the ground and slightly bent. |
Snout lick | Tongue runs over top of snout, usually going over the nose. |
Run away | Removing or attempting to remove oneself from altercation with conspecific; new instance counted when dog had chance to interact with other dog (stopping, looking back), but removed itself. |
Yawn | Mouth open wide with large intake of breath. |
Pull away | Removing or attempting to remove oneself from physical interaction with human. |
Mounting | Attempting to clasp or successfully clasping front legs around conspecific’s body and performing pelvic thrusts. |
On average, dogs were alone about a third of the time they were in the Quidi Vidi Dog Park. They spent about 40% of their time with humans and about 23% with another dog or dogs. Young male dogs spent more time in dyads (with one other dog) than was true of females of any age. The researchers observed that “dogs that displayed more agonistic behaviours tended to exhibit more stress-related behaviours.” (Perhaps it is true that bullies worry more about being bullied than most members of any species.) Hunched posture was correlated significantly with stress-related behaviors. Hunched posture also correlated highly with tucked tail, and the latter with “run away.” Exaggerated approach correlated with play bow.
“Only males mounted and of the seven males that did so, three were sexually intact.” There were no sexually receptive females, however, so mounting occurred outside of a sexual context, and was determined to occur “mainly in the context of play.”
“Only males mounted and of the seven males that did so, three were sexually intact.” There were no sexually receptive females, however, so mounting occurred outside of a sexual context, and was determined to occur “mainly in the context of play.”
Agonistic behaviors were, according to the researchers, fairly rare. This has been our personal experience as well. An aggressive dog, or one prone to attacking, is uncommon in most dog parks. Owners will sooner or later put pressure on someone with such a dog to get control or leave.
Cortisol Levels
Cortisol levels increased more from visits to the dog park than from taking walks. Cortisol levels in five dogs were negatively correlated with the number of visits to the park. That is, for some dogs that came infrequently to the park, cortisol levels were very high upon making a visit. Hunched posture correlated significantly with cortisol levels.
Dogs that had not visited the park for some time tended to show more stress-related behaviors. Thus, “dogs that had visited the park within 1 week of the test session showed significantly fewer behavioural indicators of stress than those which had visited more than a week prior to the session.” The researchers hypothesized:
“Taken together, these data suggest that the increase in cortisol seen in dogs in the dog park is caused by at least two processes: first, most dogs are likely emotionally and physiologically aroused by the presence of conspecifics [other dogs], both familiar and unfamiliar, and by the dog park’s physical environment, resulting in increased cortisol; second, dogs who are not frequent or recent visitors are likely additionally aroused, or stressed, by the novelty of the dog park setting, thereby contributing to higher cortisol levels (in dogs that visit rarely), or to higher stress-related behaviour frequencies (in dogs which are not rare visitors, but which had not visited the park within the past week). An additional reason for increased cortisol in some dogs in the dog park may be related to their underlying predisposition towards fearfulness. In this study, dogs which scored high in the MCPQ-R Neuroticism dimension showed higher frequencies of hunched posture, but not higher levels of cortisol. This may be due to the fact that less fearful/low neurotic dogs in this setting show arousal-induced increases in cortisol that may mask any relationship between neuroticism and cortisol. Those dogs showing hunched posture are arguably the most stressed dogs in the park, as the frequency of hunched posture also correlated highly with the frequency of total stress behaviours, and more specifically, with the behaviours of tucked tail and run away.”
The researchers suggest that “owners of dogs showing lowered posture in the dog park might be advised to reconsider exposing their dog to this setting for welfare reasons.”
Extraversion in Owners and Dogs
Dogs that visited the Quidi Vidi Dog Park were significantly higher in Extraversion than in a prior study of a large group of dogs.
“This may imply that the dogs in our sample represent a subset of the dog population, i.e., highly extraverted dogs, which are described by their owners as highly active, energetic, excitable, hyperactive, lively and restless…. It is possible that the owners of such dogs are more likely to bring their dogs to an off-leash park than are owners of less active dogs to provide them with opportunities to socialize and exercise. Alternatively, dogs that attend the dog park may become more extraverted through that process, as they have opportunities to be physically active and to socialize.”
Our prediction that dog parks will lead to sociological studies of humans may have to be modified to say that a comprehensive study should include both human and canine behavior.
Conclusion
The researchers conclude that most dogs, “especially those which owners rate as physically active and friendly, appear to have overall positive experiences in the dog park, and likely benefit from the physical activity and social interactions that such a setting provides.” The researchers note that a study on factors that relate to dog park attendance patterns and behavior outcomes is warranted. If the dog park phenomenon continues to grow, as seems to us inevitable, such studies will surely follow.
Thanks to Fran Breitkopf for comments on this blog. Thanks to Dr. Walsh for providing the pictures of the Quidi Vidi Dog Park.
Sources:
Ottenheimer Carrier, L, Cyr, A., Anderson, R.E., and Walsh, C.J. (2013). Exploring the Dog Park: Relationship between Social Behaviours, Personality, and Cortisol in Companion Dogs. Applied Animal Behaviour Science, posted online 2013)
Horváth, Z., Igyártó, B.Z., Magyar, A., and Miklósi, A. (2007). Three Different Coping Styles in Police Dogs Exposed to a Short-Term Challenge. Hormones and Behavior, 52, 621–630.
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