The terms “scent detection” and “scent discrimination” refer to the ability to detect odor and to identify one odor from another. The powerful ability to detect and discriminate odor by dogs has been widely utilized by people.
Police and customs dogs are trained to locate narcotics, currency, counterfeit currency and weapons while other dogs work at border crossings to find prohibited products like certain agricultural products or parts of endangered species.
At the Czech Republic Police Regional Headquarters, 10 specially trained police dogs have been able to distinguish the individual scents of identical and non-identical twins even though each pair of twins tested lived in the same house and ate the same food as one another.
Police in France have used trained German and Belgian shepherds to help resolve criminal cases. These detection dogs undergo a two-year training program and then are able to establish whether an individual has been present at a crime scene. The dogs have helped resolve 162 cases.
A rescued male German Shepherd cross named “Frankie” dog was trained to identify the presence of thyroid cancer in humans with an 88.2 percent accuracy. The study’s lead investigator David Bodenner, MD, PhD, from the University of Arkansas, said that scent dogs could be used to detect cancer (through the scent of human urine samples.) at early stages and assist in avoiding unnecessary surgery. He also said that the usual method of diagnosing thyroid cancer involves fine-needle aspiration which is more invasive and only very slightly more accurate than the results obtained by “Frankie”.
In Argentina, “Train”, a scat detection dog and his handler assisted scientists by identifying scat of jaguars, pumas, ocelots, oncillas, and bush dogs which the scientists collected and analyzed. The scientists could then develop models for movement corridors between that region’s protected areas.
There are many other ways dogs work in scent detection but scent detection is not just for working dogs. Family dogs can do this too and there seems to be an activity and organization for every interest. For those who like to test their training, there are trials and competitions. The work can also be useful. For example, dogs can learn to find items for their owners and recover missing pets or join a dn Search and Rescue organization and search for missing people.
Tracking, trailing and scent discrimination are three popular activities.
In tracking, the dog follows a scent a human has laid out for them. The dog follows the track where the handler thinks the scent is. The trailing dog is given the scent they need to locate and follows that scent wherever it is strongest. The handler learns to read the body language of their dog so they can interpret the behavior to assess whether the dog is still following the scent, or has switched to another scent or has lost scent. Dogs will “alert” when they have found the scent. Trailing dogs also discriminate between odors. For example, dogs who are trained to search for missing dogs are trained around “decoy” dogs so that the search dog learns to focus on the missing dog and ignore other dogs who may be in the area. They are also trained to give an indication that they have not found the scent.
Other scent discrimination exercises can involve identifying an individual human scent while others use essential oils and other odor sources. In these activities, the dog is trained to find the odor source on certain items or in containers, vehicles and indoor and outdoor search areas depending on the individual scent discrimination activity.
Doing scent work is tiring for dogs and builds confidence in a dog. Dogs who seemingly cannot calm down even after a lot of exercises tend to calm down when doing scent detection. It is also a lot of fun!
Jane Bowers, B.A., CABC, CPDT-KA
Jane Bowers has been training dogs for over two decades. She teaches people to train their dogs in group and private training courses and has a keen interest in assisting dogs with behavioral issues. Her company is Dogs of Distinction Canine Training Inc. Jane has a monthly newspaper column on dog-related topics and is a former host of a live call in TV show on animals. She is a strong advocate for force-free and humane training methods for all animals. Jane has a degree in psychology and is certified as a dog trainer through the "Certification Council of Professional Pet Dog Trainers" and as a behaviour consultant through the "International Association of Behavior Consultants" and through the "Association of Animal Behavior Professionals". These organizations require a minimum number of continuing education units be obtained to retain certification. She is also a professional member of "The Pet Professional Guild," an organization committed to force-free training of animals and the "Association of Professional Dog Trainers," a professional organization of individual trainers who are committed to being better trainers through education. Jane is the content creator of the online course "Assessing and Interpreting Dog Behaviour," which is a course for law enforcement personnel who meet unfamiliar dogs in the course of their duties. She is the author of "Perfect Puppy Parenting," a guide to raising a happy, confident, well-behaved dog. Jane spent 17 years working for Customs Border Services and in joint teams with US Homeland Security and the RCMP. She spent a further 8 years working as an Animal Control Officer and Bylaw Enforcement Officer. Jane lives on a small farm with dogs, sheep, donkeys, and chickens. The dogs each came from situations that prevented them from living in their original homes. The dogs range in size and age and with the dog training and behavioral work, whether it's participating in the development of an online training course, working with a client's dog or tracking a lost pet or animal.