Trailing Canine

Trailing dogs, like Joe Potter's Hank in the picture are trained to follow a persons trail.  Trailing dogs use a scent article from a person that they are trying to find.  The dog is trained to sniff the scent article when the handler presents it, find that scent and follow the scent left behind by the person they are looking for.  The scent can be moved by wind and other environmental factors, so the canine doesn't actually follow the persons track (like a tracking dog), they follow the scent trail until it leads to the person they are looking for.  The canine most usually associated with trailing work is the Bloodhound, but many breeds including Beagles, Labrador Retrievers and other working dogs can do trailing as well.