When was the last time you asked your canine companion, “What would you like to do today?” I, personally, feel this is a question we should ask our dogs a couple of times a week. After all, they have a life, too.
For many years, my canine companion was Lesal, a Weimaraner. I had successfully competed with her in obedience trials. We had also participated in “search and rescue” training and tracking. Everything that we did together was related to scent-specific work. In our spare time, we went to the lake and Lesal swam. We bush walked and in general enjoyed ourselves and each other’s company, no matter what we were doing or where we were. Still, she was getting bored.
I’d read an article in an American magazine on “sniffer-dogs” that sniffed out termites and dogs that detected accelerants. Sniffer dogs are used for detecting drugs, explosives, dead human bodies, termites, contraband food, and for tracking missing persons. Dogs have a sense of smell which is much more sensitive than that of humans. Dogs smell parts per billion. Humans can only smell parts per million. Dogs also have much greater discriminatory powers and can therefore respond much more quickly to target scents.
Their physical abilities and their desire to please people enable dogs to thoroughly scan a large area at a fire scene in a relatively short time. Dogs sample the headspace above the fire debris with their olfactory senses and use their discriminatory powers to determine if the detected hydrocarbons originated from an accelerant. Their discriminatory powers are finely tuned through the training procedure.
All of my work and training with Lesal over the previous few years had involved different forms of scent discrimination. I decided to see if I could train her to be an arson and fraud investigator. Arson and fraud detection was just another aspect of scent training for her.
Lesal and I got to work. I contacted people in the U.S. and got as much information and watched as many videos as I could. These introduced both of us to the world of fire investigation and arson-related fraud. At first, our training involved Lesal sniffing out petrol, diesel, turpentine, kerosene, and a few other accelerants. It was important to train her so that she could not only sniff out the accelerant itself, but also vapors after it had been burned. We played hide and seek with her toys (which carried the target scent) and not a day went by when we didn’t play/train.
After a few months, Lesal was extremely proficient at finding any article, debris, or fragments of soil, concrete, or timber that carried the target scent. She enjoyed every minute of this new game. At nine years old, she was still a pup mentally, but not quite physically. She was a little arthritic in the back end, but that didn’t stop her eagerness, playfulness, and enthusiasm. The reward at the end of a training session was an enjoyable game of fetch and lots of hugs and cuddles.
My method of scent training generally involved a series of exercises utilizing the dog’s aggressive prey drive, where the dog routinely retrieves a hidden favorite toy carrying a drop of the target scent. Upon successfully retrieving the toy, the dog is rewarded with affection or a play with the toy. I know when the dog has found the target scent by the change in its body language. The training then progresses to the toys carrying a micro liter of the target scent, an amount generally unidentifiable to the human olfactory system. These toys are then aged, exposing them to all manner of environmental conditions, harsh sun, rain, wind, and contaminates such as dirt, soot, food odors, and other non-toxic chemicals.
Lesal could discriminate between accelerant vapors and vapors such as those coming from burned plastics, burned rubber-backed carpet, and paints. The difficult thing, of course, was that she must reliably perform this task amongst a background composed of thousands of different chemicals originating from burnt furniture and building materials.
Our first suspicious fire scene was a large commercial building with considerable structural damage. Lesal dealt with the fact that there were gaping cavities in the floor and debris that had to be climbed over. There were also the remnants of wiring that she kept getting caught up in, but she took it in stride, as it was all a big game to her. When a forensic scientist analyzed the areas of debris indicated by Lesal, it proved beyond a shadow of a doubt that there had been an introduced accelerant to start the fire. Three weeks after the fire, Lesal was able to indicate the point of entry and the arsonist’s movements throughout the building.
A couple of weeks after that fire, we were called upon to investigate another suspicious fire scene at a building construction site in an upper class harbor side suburb. Upon arrival, it was difficult to tell that a fire had occurred. The building was a mansion, two stories high, on the edge of Sydney Harbor. Builders had constructed a scaffold so that Lesal and I could access the top story, because there was no internal staircase. Lesal thought this was great and ran backwards and forwards, up and down the narrow plank that led up to the first floor. On the other hand, there was no way that I could be convinced to walk across that narrow gangplank. The investigator eventually managed to get me a ladder up to the mezzanine level.
Once up there, Lesal got to work, sniffing and climbing around the piles of building materials. Then, she discovered the bathroom and climbed the walls via the enormous spa bath, “It’s up there,” She kept telling me. “Up there!” The spa was full of debris that had fallen down from the ceiling, but this did not deter Lesal. She dug, climbed, and scratched — a very excited Lesal. She told us very clearly of the arsonist’s movements.
Today, my dogs are Molly and Skye. Again, both Weimaraners, and they have been trained in this way as successfully as Lesal. The dogs have been rated by forensic experts at suspicious fire scenes. These forensic experts then take samples of the debris where the dog has indicated a target and then analyze it using a portable gas chromatograph. These machines indicate if there are accelerants present in the debris, and, if so, which chemicals and to what degree.
Merely introducing the dogs to fire scenes does not of course mean that arson was the cause; the dogs are just as useful in ruling out the possibility of arson. When this happens, it means that the investigators can focus their efforts on other possible scenarios.
Tags: Lesal, Rescue Dog, sniffer dogs, Weimaraners
