The most powerful of all canine senses is the olfactory sense of smell. The average dog has around 220 million receptors in their nose compared to the average human with 5 million (source: "The Dog"s Mind", Dr. Bruce Fogle). Being just an average, some breeds are much better in their scenting abilities than others (bloodhounds, beagles for example). While scent is without a doubt the most important of a dog's 'practical' senses, it is also the most difficult for us to comprehend. Frequently it is said that odours literally play tunes in the dog's nose!
In tracking, we take advantage of a dog's natural and powerful scenting abilities and teach it to follow a previously laid 'track' along which specific articles have been dropped. The object of the training is two-fold; first, to precisely follow the laid track and second, to 'indicate' finding these articles by either lying down (or sitting) with the article between the dog's front paws.
There are many 'styles' of tracking. Some dogs are taught to 'air scent' (i.e. lift their heads from the ground to smell the air that is carrying the scent). This type of tracking produces dogs that are 'in a hurry' to get to the end of the track. Other dogs are taught to alternate between ground and air scenting and become comfortable at alternating based on where the scent is stronger (ground or air).
There are many practical applications of tracking in everyday life. Police dogs use an alternating air/ground scenting style to pick up the scent of a suspect when in pursuit. They follow both the naturally shedded dead skin cells as well as the scent of adrenaline, sweat, crushed ground cover and like disturbances when tracking. A similar style of tracking is used by search and rescue dogs where time is of the essence in following the track and pursuing an individual in need of being rescued.
In contrast, "deep nose (Schutzhund-style) tracking" is where the dog learns to methodically follow the footsteps of a person who previously laid the track while 'indicating' (by laying down or sitting in a specific manner) articles that have been left behind on the track by the tracklayer. The dog is slow, deliberate and precise in this style of tracking. The terrains used to teach a dog to track vary in size and type as does the distance the handler can be from his dog. Eventually, the schutzhund-trained Tracking Dog will learn to track the footsteps of a tracklayer who laid the track two hours prior, with his handler being 30 feet behind. This style of tracking is used to train dogs to track down their objective when time is not of the essence, for example search and recovery (cadaver) dogs are known to use this type of tracking. In direct contrast to search and rescue operations, delaying using search and recovery dogs actually assists in the task of recovery as natural decomposition produces much stronger scents.
In CKC tracking, the style is somewhat less precise compared to that of schutzhund-style tracking. Dogs that enter in these tracking trials are permitted to veer off the track laid by a tracklayer and are not disqualified as long as they are visibly continuing to 'work' and do not lose interest. Tracking speed and style is also unimportant as long as the goal of finding and indicating the article(s) left on the track in a certain manner are achieved. In contrast to scoring in the Schutzhund tracking phase, a pass or fail grade is awarded in CKC tracking.
In tracking, beginner dogs are taught in a purely motivational way - there is no room for compulsion and corrections on the track, otherwise the connection and bond between the handler and the dog is lost. Although, who's kidding who, eventually all we are left to do is follow thirty (or more) feet behind and document whether or not the article indication happened where it should have! The dog, upon understanding what is expected of her, will take over the hard part of the job!
Unlike other trials where trialing dogs enter a ring and are often surrounded by other dogs and handlers practising before their turn (and generally a great deal of barking and dog-commotion), tracking is essentially a solitary dog sport where the dogs and their handlers learn to work together as a cohesive team while being separate from other dogs. Tracking trials are therefore ideally suited for dogs that may have behavioural difficulties being in the presence of other dogs and/or strangers.