Dogs track walking humans
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TRAILING DOGS
The trailing dog is often referred to as a "tracking" dog, although "tracking" and "trailing" are not the same to the purist. The trailing dog is directed to find a specific person by
following minute particles of human tissue or skin cells cast off by the person as he or she travels. These heavier-than-air particles, which contain this person's scent, will normally be close to the ground or on nearby foliage, so the trailing dog will frequently have its "nose the ground," unlike the air scent dog.
A Bloodhound is typically trained for scent discrimination. Each dog is usually worked in a harness, on a leash, and given an uncontaminated scent article (such as a piece of clothing) belonging to the missing person. The dog follows that scent and no other. At times, the dog may track, following the person's footsteps,
or air scent, and home in on the subject's scent.
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