by paul vallandigham on Wed Aug 30, 2006 2:29 pm
Actaully, a well trained dog is not going to be thrown off your scent easily. Getting into a car that is completely closed, and driving on a very busy interstate highway, so that there are lots of cars and trucks to disperse the dead skin cells( rafts) that carry your personal scent signature, may possibly do it, but I know of one televised case where a dog followed the scent from one exit to the next, and actually found the exit where the suspect drove off the interstate.
There are things that can be used to interrupt a dogs scent glands for awhile, preventing him from following a scent trail further, but I would rather not discuss them here. And there are drugs that can be used that will actually kill the dog if he is following your scent and gets a whiff of them, but I will not mention them here.
As to rivers and streams, air scenting, as opposed to ground scenting, dog are actually able to smell your scent in the air above the waters, and pick your scent back up on the other bank. You would have to travel downstream in the water for a long distance to lose the dog and his handlers, who would rather work the riverbank than actually go into the water to follow you. Today, you then have to deal with airplanes and helicopters and heat imaging devices that can see you in the woods, where you might hide.
I worked with a master K-9 trainer teaching visual tracking skills to his k-9 officers, and helped him while he taught scent work to the officers and dogs. We laid out scent tracking problems, both for practice, and for training. One of my best friends, who was a tracker, and also was working his own bloodhounds, ran a trial course for an AKC event, where the trail went through a drainage ditch. The track layer had waded up the stream aaout 50 feet and then climbed out of the ditch on the opposite bank. There was so much disturbance of the grass and weeds that lined the bank that it was easy for Don to see where he came out from where the tracks entered the water. Although the tracks had been layed hours before Don ran the course, his bloodhound had no trouble following the scent up stream, and she tracked the man into a crowded pavillion at a county fair site, and went right up to him where he was sitting up on some bleachers.
When you understand where the scent the dog is smelling comes from, and that is not just an aroma wafting in the breeze, you understand how difficult it is to lose a scenting dog. 65% of your body heat escapes off the nape of you neck and back of your head. With it goes thousands of dead skin cells. You shirt sleeves act like funnels forcing air out and throwing out thousands of skin cells . Your pant legs likewise act like huge pepper shakers, and send out thousands of dead skin cells with every step. Run, and the shaker puts down more cells. The cells are attacked by bacteria, and as they decompose as they are eaten, they give off the odor the dog is sniffing. If it was not for the presense of bacteria, we would be buried in miles of thick layers of bones, and dead skin cells. In fact, Life could not exist without the bacteria that live in the air, and soil.d So, it only takes a well trained dog handler, and a well trained and practiced scenting dog, to follow a trail. The handler is more likely to wear out than the dog will. And, if they get off trail, it is almost always handler error that is responsible for the move. Even my friend, the master K-9 instructor screwed up during a practice session one day, pulling his dog off my scent, to wander off after some visible tracks made several days before by someone working on the grounds. I purposely stopped when I saw those tracks. stomped my feet several times, scuffed the ground to bleed the vegetation to give a ripe odor, before walking on in the same direction I had been heading before seeing the cross tracks. He was embarrassed, but admitted that this was the very reason he wanted to do this practice session, as he had not run his dog on a scent trail in weeks, and was afraid he was getting rusty!
That dog , a few years later, back tracks a man who was found hanged in a tree through the woods( going from strong scent to weaker scent) to the man's car, where they fond his wallet and car keys, and found a note on the front seat with a map showing the path he was going to walk through those woods to the tree he had chosen to use to commit suicide. My friend had then the only dog certified to be able to do back tracking scent work, and I know of no other case in Illinois, where such a feat was done, and verified not only by footprints found on the trail, but by the victim's own map. Police found a suicide note at his home. He is one heckova trainer, and that was one fine dog.