Dogs have an amazing sense of smell and benefit from opportunities to sniff. Particularly in the stressful environment of animal shelters, there is great interest in finding ways to improve welfare, and scent enrichment is one potential avenue. This study examined the effects that two common scent activities had on overnight activity and stress-related behaviors of dogs in a United States shelter. Dogs were included in the study for three consecutive days and were assigned to the Sniff Walk, Nose Work, or Control group. During their inclusion, they wore collar-mounted accelerometers which recorded the time overnight they spent resting versus active. Cameras were set up on their kennels; for one hour each evening, video was taken and analysed to determine the amount of time spent in various positions (lying, sitting, standing, or moving) and performing stress-related behaviours (vocalising, spinning, pacing).

On the second and third day of inclusion in the study, just before the shelter closed for the evening, dogs in the Sniff Walk group were walked using a long line and were allowed to stop to sniff as much as they chose. Dogs in the Nose Work group practiced an exercise in which they searched for treats in boxes. Dogs in the Control group got the usual routine of time in a play yard or a “normal” walk on a 6-ft lead. There was no significant effect of either scent exercise on the overnight activity levels of dogs or the frequency with which they showed stress-related behaviors. Despite the lack of significant effect shown, this study demonstrated that both scent exercises were easy and inexpensive to implement in the shelter setting. Future studies with larger sample sizes and longer periods of inclusion for each dog may better highlight the potential benefit of these activities for dogs living in shelters.