How do SAR dogs work?

How do Search Dogs Find Missing People?

Back in the olden days when dogs were bred for certain work, like German Shepards and Boarder Collies for herding or Catahoula Leopard Dogs for hunting wild boar or Labrador Retrievers and Golden Retreivers hunt birds, we take that natural instint to go after their prey and direct it towards humans. 

Starting this process young is preferable although some older dogs (2-4 years old) have worked in the past. This is due to the process of training and certifying a dog takes around 2 years. By the time the dog is certified, they only have so many years as a deployable SAR K9 until health issues and old age sets in, the dog will retire sometime around 10 years old. 

Humans constantly shed skin cells which hold a unique scent of ourselves. I like to relate this to a person holding a smoke bomb (like what we see on the 4th of July). We can see that if there is a slight breeze, the smoke will shift to blow with the wind. We are constantly doing this! If someone sits in a spot for a long time, the amount of scent we have produced is insanely large. That scent pool is what our dogs are after. They want the largest, freshest scent pool because more times than not, that scent pool is for the missing person we are after!  

Where scent decides to stick is constantly changing throughout the day. It is up to the K9 Handler to set the team up for success by knowing where the wind is pointing, what the temperature and humidity is like, what time of the day it is, and the conditions of the search area are like. 

Although nobody can truly say they know scent theory, we can have a basic understanding. An example is that if it is above 70 degrees with no cloud cover in downtown and a trailing team is deployed to find grandma, the dog will refuse to work. It is as simple as that since the scent has nowhere to fully stick to and it will rise, most likely dumping somewhere far from the actual trail grandma walked. When you're walking on a sunny day in the city, you can see that just down the street, there is a mirage made from the heat of the concrete, right? The scent of the missing person won't stick to the grass or the road. It'll be balancing on that mirage of heat, constantly moving since it cannot stick anywhere.  

 

How do SAR K9's lock onto a specific scent if there are tens of hundreds of people walking around at any given moment? Imagine that somewhere in your neighborhood, someone is cooking steak for dinner out on the barbeque. You can smell that charcol, the meat, the seasoning, you think to yourself "Oh man, I wonder who is having that for dinner tonight!" Right? You can stick your nose up into the air and know that without a doubt that someone is cooking steak in the area. Continuing with that analogy, you can go on a walk and figure out which house it is exactly that is cooking the steak. The Airscent and HRD dogs will put their nose up into the air and without a doubt, they know that there is somebody with a massive scent pool, they will range out and figure out exactly where that scent pool is.