The most amazing feat of a detection dog is how they understand scent behavior and how the dog is able to use scent to find what they are looking for. Olfaction, the sense of smell, is the least understood of the five senses.
Therefore, the more you know about how scent behaves the better you will understand or read your dog when you both are looking for clues to where a person went or where they are buried in rubble.
Scent is defined in the Encarta Dictionary as a pleasant smell or a smell used as trail, or a perfume. The word is also defined as a smelling sense and as a hint or indication that something is likely to happen.
The scent a search dog follows is actually skin and chemical particles along with oils that are so small in size we cannot see the dander unless they accumulate to the point of dandruff or oily skin complaints.
The chemicals that are mixed in with our natural odor come from the soaps and man made items we come into contact with. Everything we come into contact with contaminates our own personal body aroma.
These particles are shed ever minute of our lives and constantly changing but remain somewhat the same to distinguish each of us by our very own scent print similar to a fingerprint.
Whenever we stand, sit or lay a “scent pool” of particles falls, so invisible to our naked eye yet enticing to our 4 legged friends, these particles settle until a wind or movement swirls them to mix with other scents.
As we walk we leave behind a scent trail no matter how hard we try not to do so, we will leave particles behind.
When a person attempts to cover or clock their scent all they are really doing is adding to the unique mixture of ingredients which make up the scent. The overall scent may change but the ingredients remains and a dog taught to discriminate scents can detect even the smallest percentage of the scent they are looking for in the ingredients.
The wind and motion around the scent or person plays a role by moving the scent around and when two people come together their scents mix but a dog who is asked in the correct way can show you which person is the one they first set out to find.
We are never really alone and on every leaf or grain of sand we pass outdoors our scent settles, sometimes on branches several feet away where a particle of us may linger for days, weeks and indefinitely depending on the weather or inside climate conditions.
As our scent drifts to sit upon a surface the wind or motion moves it but eventually like all things, the scent will fall to the lowest surface we cross. As we step up a curb from the street our scent falls to the cracks and crevasses of the street and sidewalk. Everywhere we go, a piece of us is left behind.
The slower a person walks the heavier the scent trail remains because the particles have more time to settle in place.
This is true with less windy conditions too. The faster a person walks the less the scent will be contained in a trail or path because the motion dispenses more scent over a large pathway making concentration of scent but a larger area.
This is why a Bloodhound will track 3 or 4 feet off to one side of a person’s actually path of travel. This is always why we do not ask search dogs to stay exactly on a person’s foot print which can slow us down in finding the person.
Scent trails can be affected by drafts that are created from buildings or clear cut areas, roads, ditches and tunnels all can make a draft. A scent trail that comes out of the wooded area to cross a narrow road to another wooded area will hit a draft at the road.
The road will be like a tunnel the wind and air has more space to move the scent around and the scent will drift more regardless of the speed of the wind or even if there is a wind. In a city or urban setting the buildings, alley ways and all of a sudden open spaces create a draft to move scents.
Watch a novice dog at these crosses to learn how your dog will work a drafted area and follow your dog through the puzzle.
Never try to trick a tracking dog or trailing dog because you will only make the dog not trust you to give them the correct scent. A dog will refuse or ignore your wishes if they cannot trust you to know what you want.
A dog smells all the ingredients of a scent and it is up to us to tell them which scent particle we wish to find.
Caution: A dog’s nose can be damaged or desensitized by chemicals and common household cleaning agents or smells depending how close the nose comes to the produce. Never hold any scent to close to your dog’s nose.
Allow your dog to reach over to the scent at their own speed and distance because the dog knows how close they can get to the scent. They have actually smelt the scent long before you called them over to have a smell.
The average dog has a sense of smell much greater then man’s, some say as much as 1 million times greater then ours. Plus they can smell each ingredient which we cannot unless we practice or know beforehand what to notice.
Learning how scent behaves will help you to read your dog for clues that can help you find a missing person or evidence of the person’s whereabouts faster and help you to understand what your dog is telling you.
This lesson gives you the basic idea of how scent plays a role in your dog finding a person.
There are many good books on the subject of scent which can be very complex but interesting reading that will help you to learn how to read your dog better.
Every effort should be made to prevent contamination at the LKL (see glossary page) by other scents, including people at the location or on the scent article you collect.
Once contamination overpowers the person's scent on a scent article or location the dog has a much harder puzzle to figure out and often will become confused which is where the importance of " preventing the contamination the scene or article" comes into play.
I will cover how to secure a search dog location to work in later lessons, be sure to subscribe at the easy link at the left or below so you do not miss a lesson.
The next lesson will explain how handlers read their dogs for clues that help the dog communicate what they find along the trail route.