Trailing and tracking are commonly mistaken, and the phrases are sometimes used interchangeably. Tracking relies on the visual impression of an event by humans in the form of observable tracks or spoor. I believe the phrase is incorrectly applied to our understanding of events that only the dog can observe. Typically, tracking with a dog requires the animal to follow a certain set of footsteps without deviating. Typically, the dog’s nose is driven to the ground by a leash that runs under his thigh and around his neck. The lead pushes the dog’s head down as the handler applies tension, supposedly to keep the dog’s nose in the smell zone of the footprint. My objection has always been: How do you know the footprint has a scent? This article explores the nuances and strategies of scent trailing. It will hopefully offer a deeper knowledge of how K-9s use human scent to pinpoint a specific individual.
There are several variants on the “tracking” subject, but they all ultimately refer to the same thing: a dog’s nose in human footprints on a soft surface. Once the paradigm transforms to that of a hard surface, such as any roadway in any modern urban jungle, the police K-9′s capacity to track footsteps that are now invisible is nearly eliminated. This is true not because of the breed or the aptitude of the dog, but because of the nature of the K-9’s training.
The principle underlying track is twofold:
- The footstep that generated the ground disturbance is the odor that the dogs pursue.
- The footprints are the most concentrated source of human odor. It is simple to understand why so many early trainers had this opinion. Therefore, the perception was reality; the dog’s nose hung near the human’s actual path.
Consequently, training programs that adhered to the training concept were developed. If the dog’s nose deviated from the specified height above the track, it was immediately pushed back into place without any examination of the underlying cause. It was presumed without question that the dog was odorless. Many individuals assume that a dog must be within inches of the scent to detect it. I believe that perception stems from our own scent-limited environment and erroneous justifications. Nothing could be farther from the truth, since simple experiments have repeatedly demonstrated that most dogs can detect odors from a fixed place and at distances ranging from inches to yards and beyond. Consider the following: if it has been demonstrated that a dog can detect an odor from either a ground disturbance or the person who made it, and from more than a few inches of the physical trail, why must a dog’s nose be forced into the track?
Now, let’s analyze how paradigm alterations affect human fragrance. Step from the newly plowed corn farmer’s field onto the neighboring gravel road. You may be able to discern the human track and direction of travel if you are fortunate enough to view the trace from the beginning and if you can distinguish the subtle variations in rock discoloration from the top to the bottom. Then convert the farmer’s dirt driveway onto the adjacent roadway. The trace vanishes, making it hard for the dog to lay its nose in it. Consequently, the hard surface track is rarely successful for the ordinary police K-9, which is unfortunate.
In contrast, training is simply training a dog to follow a single human’s smell pattern wherever it may lay — on the ground or in the air — as opposed to following a specific set of footprints. If, for instance, the dog is following a scent trail on a path along which the suspect is known to have walked and detected the same odor on the wind coming from the direction where the suspect is currently located, the dog is permitted to follow the air scent and deviate from the footpath, even if the suspect did not walk in this new direction.
In contrast to a tracking dog, a trailing dog enjoys greater freedom of movement and, more significantly, independence. Ordinarily, independence in a police dog is viewed as an oxymoron; nonetheless, it is essential to recognize that smell is the dog’s world, and it is quite probable that the dog has a greater understanding of identifying it than humans. As handlers, our only responsibility is to interpret the dog’s behaviors and hold on properly. This does not imply that the dog is free to conduct himself as he pleases; rather, the relationship is founded on mutual knowledge of constraints and individual capacity.
My belief is that trailing exemplifies the dog’s natural reactions to smell patterns and duplicates or approximates what a coyote or wolf may do when tracking prey based on scent. Add smell discrimination to the mix to take this one step further. Every animal, including humans, emits a particular odor depending on its species and other sub-determining criteria, such as infirmity, relative age, sex, and specific distinguishing characteristics. The amount of odor created is determined by a number of major elements, including emotional states such as fear or rage, physical exercise, and relative health difficulties. Some folks simply smell stronger to our dogs than others. The more pungent they are, the better. The inclusion of the human handler ensures that the tracking dog stays on a particular smell for as long as possible.
The Nature of Human Scent on the Trail
Unusual smell theory knowledge is required for a handler to comprehend trailing. Every environmental or anthropogenic circumstance affects human odor and how the dog senses it. Each factor must be studied and analyzed not just before the dog begins working, but also as it performs. Trailing might be a constant length of human odor from one spot to another, or it could be a sophisticated game of linking subtle smell “dots” in many locations to reach a conclusion. The dog’s ability to track a scent is contingent upon his training and intrinsic physical characteristics.
Trailing takes into account the fact that smell does not remain in the “trail” of the hunted subject, particularly on hard surfaces. Depending on the conditions, the human fragrance of an individual strolling might potentially carry hundreds or even thousands of yards. It would be absurd to compel a dog to follow a small trail that may no longer exist in the initial location.
Consider a particularly hot, dry, and windy day in the downtown of any American city. There is little to no greenery, and the asphalt radiates heat like a quick-service restaurant grill. The asphalt’s heat reflects and eliminates aroma, and if any scent falls, it will not remain where it lands. Instead, the small particles are distributed by wind, heat waves, and physical manipulation to every potential barrier that may trap them. Objects containing moisture, such as flora, attract smell particles more than others. My hypothesis is that smell particles, or rafts, or whatever you want to name them, tend to be hydrophilic. In other words, they are drawn to damp, chilly, oxygen-rich environments. This is because all biological stuff is susceptible to biological breakdown processes. Carbon-based matter or odor-producing human particles are prone to the same sort of aerobic bacterial activity as comparable matter. As the substance degrades, so does its odor. I feel that when odor degrades, it also changes or ages. As well, it appears that some gases, such as carbon monoxide, have a deleterious impact on odor.
In regions with little to no flora, however, the smell will still gather in spots that may impede its movement or destruction. Cool, shaded places, such as the north side of a building, retain fragrance far better than flat, open stretches of hard surfaces that are exposed to solar radiation or human manipulation.
A smell trail cannot be identified visually; rather, it is invisible and must be interpreted by observing a dog’s bodily reaction to its presence or absence. It is one thing to be able to read a dog when he is working, but handlers frequently feel confused when reading a dog that is not on scent or, more crucially, when he is not on the smell he started with. Unbeknownst to the handler, the ease with which a police K-9 may switch animal or human scent tracks is uncanny, unless the handler has a unique knowledge of the dog’s subtle behavioral changes when he hops trail.
Humans are visually oriented, and our natural inclination is to reason things visually. Thus, when I explore the nature of the human odor, I attempt to make it visible, if only momentarily and in our minds. Imagine a person standing alone in the midst of a grassy park while clutching a red smoke grenade — red being the predominant color that distinguishes this individual. If there is any wind, the crimson smoke will travel with the breeze and cling to any item that can retain it, such as a tiny valley, a tree, or even grass blades. As this individual moves or walks, so does the smoke trail. Changes in environmental circumstances, such as more or less wind, rain, extreme heat, or humidity, have a larger or lesser impact on the smell trail.
Now, let’s add a second human with a different-colored smoke grenade who follows alongside the first individual’s smell trail. Both odors may remain visually distinct, but it will be difficult to distinguish between them. Complicate the situation by adding another individual, then another. There may come a time when it is nearly difficult to distinguish one hue from another. I feel that dogs face the same difficulty in different situations. Instead of imagining a scent trail, the subject smells it. Who has the simpler task?
When I am training a new dog for obedience, I try to keep the aforementioned scenarios in mind. During early training sessions, most dogs are able to distinguish between the scents of one or two persons. Adding a city street with hundreds of millions of unfamiliar odors may be a nightmare for any dog, regardless of how strong the scent is. With a clear objective in mind, trail training is best performed in simple, straightforward steps.
I expose green scent-trailing dogs to each level of smell discrimination, from little to heavily polluted. Completing the training might take up to a year, and particular approaches are necessary to assure dependability.
Trailing is sometimes equated with scent discrimination, or the capacity of a dog to recognize an individual human odor amid a large number. Regarding this topic, there are several schools of thought. Some individuals claim that dogs lack the capacity to discriminate scents and instead rely on the most recent smell track to leave an area. To adequately discuss this topic, I would need to write a book. I believe that all canids have the ability to distinguish between human and animal odors, and this is what distinguishes them as exceptional hunters in the natural environment. I do not think this capacity is 100 percent correct, though. On the track of prey, some circumstances can confuse and divert a dog. This is especially true when a dog is needed to navigate through the melting pot of human odors on a suburban or urban street. The degree to which a dog works is proportional to his training, innate characteristics, or prey drive.
The Scent Article
The key to scent discrimination, or ensuring that your dog locates and follows the intended trail, is contingent on a number of variables, the most important of which is the scented object used to initiate the trial. As a fragrance object, anything that a person has touched, handled or been in the presence of may be utilized. In the event of a crime scene, it may be difficult to discern what, if any, object is reasonably uncontaminated and robust enough to be used as a weapon against your dog. The greatest issue arises when investigators pollute the crime scene. A brief window of opportunity normally exists for locating, protecting, and exploiting a suspect’s smell. The handler should preferably be the first person on the site to discover and acquire a suitable item. In the absence of this luxury, competent first responders can also fill the need.
Frequently, everything at a crime scene may be tainted. In this situation, it is essential to recall who was present at the crime scene and who made touch with the desired smell object. There is a method known as missing member for utilizing a contaminated item. The dog is permitted to pre-sniff the individuals who have been present at the crime scene and distinguish between their scent and that of the missing person (s). Extensive, though inconclusive, is my experience with the missing member strategy. I’ve found it to be a vital tool for polluted crime scenes, although it’s not entirely dependable. Regardless, I have discovered effectiveness with this technique, and I feel it should be utilized when odorous objects are severely tainted.
The scent item is not always required for a successful trial, but it is a vital tool that the handler should always be able to recognize and apply. If they are to be used to train a trailing dog, little to medium-sized scent objects must be preserved at all costs. In my patrol car, I maintain an assortment of heavy-duty zip-top bags in various sizes. Paper bags are ineffective because they are excessively porous, and the contents soon become polluted. If an object is too delicate to be moved and handled by a K-9 handler due to its evidential importance, the next best option is to extract its fragrance. In addition, I have a supply of cheap, 4×4-inch gauze pads in the trunk of my vehicle. Simply laying the pad on the object and allowing it to rest for a few seconds can transfer the scent from most objects to the pad.
A fragrance piece does not need to be portable or baggable; it might be a stationary object, such as a windowsill, car seat, or doorknob. It might perhaps be a victim. A person who has been touched by another individual can also function as a fragrance item. This is not a simple method, but it may be used to scent the dog.
Once the following dog has been trained to differentiate smell and follow unique trails among numerous, the handler must be increasingly aware of the variety of a single scent object and how readily it can be corrupted. If the dog is to be effective, the scented piece must contain an overpowering fragrance of the subject, and the subject’s scent trail must be inside the region where the dog started. The vast majority of our tracking instruction is devoted to the nature of human smell, its collection, preservation, and presentation.
Very little contamination from other humans is required to degrade the quality of a smell product. Couple the contamination issue with the contaminator having the freshest trail out, and you have the premise for a failed scent article; in other words, the dog may simply follow the freshest path. The issue with the majority of scent-article training is that many handlers and trainers fail to account for how readily the smell article might get polluted. In addition, they seldom take countermeasures to circumvent or avoid the problem in the first place.
Scent-article and scent-discrimination training are the most vital components of the trailing continuum, although they get the least focus. The erroneous assumption is that if you merely present a dog with a scented piece containing a person’s fragrance, he would know what to do with it. When a new route has been blazed for someone else, the article is typically irrelevant.
The normal canine response appears to be to constantly pursue the most recent or strongest scent. Good scent-article training necessitates that the trainer resists the natural canine response to new scent stimuli and act counter-intuitively. Good scent discrimination training requires unique measures to guarantee that the dog can follow the scent of the handler to one door among numerous others. This does not occur easily or swiftly. Additionally, some dogs cannot be educated to “out” of the fresh or hot trail syndrome; they are so focused on quick fulfillment that selective scent selection and the following is virtually impossible for them.
The second component of good training in scent discrimination is training in smell, sight, and sound discrimination. The trailing dog must be able to navigate all three distractions with relative ease, and the handler must be able to interpret the dog’s subtle or not-so-subtle body language changes when it meets them. The trailing K-9 must be exposed to every conceivable human and animal distraction in organized circumstances where the handler can read the behavioral reaction and implement the necessary countermeasure to guarantee the K-9 continues on the trail he began on. The issue is that most dogs may switch to another human or animal track, and the ordinary handler has difficulties recognizing the changeover; hence, he follows the dog happily until the new scent peters out or until he encounters a distraction.
The kind and quality of the equipment a handler uses are crucial. This is particularly true if the K-9 team develops adept at tracking. Invariably, when this occurs, the number of service calls and the severity of the trails, especially in terms of distance, increase. I recall several 10-mile treks that not only tested my body but also destroyed my equipment. I quickly switched to goods that were more durable and sturdy. Also essential is usability. If anything was difficult to put on my dog in the dark, I did not use it.
Long lead and harness are the two most important components of K-9 gear for a trailing dog. The following dog must always be walked with a harness and never on a collar alone. The work’s intensity and length will exert an excessive amount of strain on a dog’s neck and cause health issues.
I like 20- to 30-foot leashes, which many dog trainers consider excessively long for control. When a high-drive patrol dog is let to trail rather than track, he has a predisposition to work at a rapid rate. If the dog is not given sufficient freedom to operate, the handler’s weight becomes a distraction and an anchor, increasing the likelihood of losing the trail, particularly in an urban setting. A 30-foot leash gives the dog greater mobility in expansive places, but it may be lowered to a few feet if safety becomes an issue. It requires little more than reeling in and reeling out. Most handlers do not train enough with the long lead to feel comfortable with it: lead control and plenty of practice are the keys to success.
After considerable trial and error on the tracks with my hefty Bloodhounds, I landed on a rather large, draft-horse-style leather harness that looks cumbersome but proved to be really comfortable for my dog and simple to put on. The breast pad was fashioned from double-thick, 12-ounce leather that was very broad and smooth, therefore decreasing fatigue and skin abrasion by dispersing the force of resistance across a vast surface area of my dog’s chest. Attached to this was a 30-foot leather lead constructed from 14 to 16 ounces of the rolled bull hide. This sort of leather is uncommon and in high demand. It provides a very strong and resilient connection between the handler and the dog. It does not tangle easily and, more importantly, it does not burn the hand when the leather is shot through a loose hold if the dog decides to fire.
Many individuals may question the necessity for such durability and price in dog-trailing equipment, but I have found that you get what you pay for. A training deployment might span anything from a few yards to many miles, thus it is essential that the trailing dog has quality equipment. No expenditure is too big when it comes to the life-or-death duties of a tracking police canine.
I quickly realized that for my own equipment, a lighter was preferable. If I anticipated the journey to be lengthy and challenging, I brought very little. In the trunk of my patrol vehicle, I always maintained a pistol belt with my sidearm, an extra magazine, and a water bottle. I would replace that equipment with the Sam Brown leather I always wore on patrol. Later, I switched to a water-carrying bag like a Camelbak. Boots were always essential, and I had to be able to run great distances in them without developing foot pain. I rapidly realized that beauty was irrelevant and that only my bodily comfort mattered. If I grew fatigued or hurt a short distance into any path, my ability to interpret my dog’s behavior was impaired. It goes without saying that traditional wool outfits are terrible for running. Blends of polyester and cotton are significantly more comfortable. Obviously, what an officer carries on the field is a combination of personal choice and agency directives.
First On The Scene
The optimal circumstance for a squad in pursuit is to get on the site first. If the K-9 handler has the luxury of coming immediately, he or she will be able to scan the situation and evaluate all of the circumstances that will have a favorable or negative impact on the dog. Consider how your environment may distract your dog from working. If, for instance, neighborhood dogs are making a ruckus and might be a distraction if your route passes directly by them, determine whether it is possible to temporarily confine them indoors.
If authorities are already patrolling the area, check if you can slow them down or maybe temporarily suspend them while you get your dog started on the trail. If the K-9 detects a smell and discovers a trail, the investigation will be restarted. There is nothing superior to a good, scent-discriminating, tracking dog for locating evidence, and a skilled handler will minimize the risk of upsetting existing evidence. Occasionally, a well-intentioned investigating officer will accidentally touch or contaminate your targeted small piece and leave the location on his or her scent trail. If the officer’s smell was the most recent on the object and he or she has the most recent scent trail leaving the location, your dog will follow the officer. This has occurred to me several times.
If you are unable to be on the scene immediately, inquire with a responsible party about individuals who have come and gone, where they have been, and, if feasible, what they were doing. Better better, if everyone is still there, let your dog scent each individual before you begin your trail. It is simple and can be completed in a few seconds.
When I get to the crime site, I gather a summary of how the event unfolded without going into excessive detail. I am interested in travel directions and specific witness testimonies, so long as they are accurate.
Contrary to popular opinion, witnesses frequently lie, either to satisfy their own egos or to make an impression on authorities. I take witness testimony with a grain of salt and interpret my dog’s behavior for indications of the genuine departure track. Once I have a broad understanding of the scenario, I search for my favorite smell item, collect it if feasible, bag it, label it, and store it safely. If someone has handled my item, I make sure they are present when I start my dog. Thus, I will have a far greater chance of locating the suspect’s trail.
My final step is to give my dog rest and let him explore the area on his own. This is an ideal moment for him to urinate, and it also affords him the opportunity to scent-inventory the area beyond the site. I attempt to make one complete round around the area with my dog on a short leash and by the collar, and then I walk him by every remaining person. This can occur with relative rapidity and velocity. Depending on the nature of the crime and the suspect’s mental state, the suspect may have left a trail that stands out from the others. Occasionally, when we are strolling, my dog will abruptly jerk his head in a certain direction. I document this response but do not endorse it just yet. The path has not yet begun, and we have not yet begun working. The head pop may signal a suspect’s direction of movement, or it may signify that my dog has seen his greatest police partner. Catalog but do not encourage.
Beginning the scenting process with your dog might be difficult. Many individuals assume that the ideal location is where the suspect was last seen. This may not always be physically or olfactorily simple for the dog. Often, the smell scenario is the worst circumstance. If the place has last seen (PLS) is the suspect’s house or a frequented spot, enormous quantities of the suspect’s smell may permeate the region, generating a big scent pool with several departure points of varied ages. This can be perplexing for even the most skilled tracking dog.
His past training routine is the common denominator among dogs who cannot find their way out of a vast or confusing smell pool. Typically, handlers train their dogs in reasonably “clean” places or in the same regions again. Rarely are fragrance simulations created to resemble genuine crime scenes. As soon as my tracking dog has mastered the fundamentals of his art, all of our subsequent training will be conducted with smell contamination and diversions in mind.
When I meet a situation in which my dog has difficulty escaping, and the scented piece is not to blame, I must evaluate two alternatives. First, the person I am searching for may not have been there in the first place, or second, the smell trail may be too masked or tainted; thus, it is time to search the perimeter. I employ a time-honored visual tracking approach to assist me to discover a new track when the old ones disappear. I train my dog in predefined concentric rings beginning at the origin. The distance between each circle will vary based on terrain and weather, but I prefer to maintain 20- to 30-foot intervals. I continue the rounds until either my dog catches the scent or it becomes evident that he has found nothing and it is time to stop. If you push a dog long enough, he will likely choose a path just to please you. A dog that has never been exposed to this sort of task cannot be expected to perform it effectively. As with any duty, the dog must be trained for this one as well. I begin by providing a trail for the dog on the first circuit, and once he has mastered it, I expand the size of the circuit or add another.
Reading A Trailing Dog
Most handlers struggle the most with reading their dog correctly. This is particularly true when the path is an authentic one. Every time you work on a genuine case, you must recruit the assistance of a cover guy. The cover man acts as an additional pair of eyes and ears for the handler, keeping an eye out for obstructions, dangers, and diversions. This permits the handler to see his or her dog without being distracted.
Every scent-trailing dog shows distinct actions when on a smell trail. However, each dog is different. It is erroneous to assume that a specific tail position or headset is the same for every K-9. When a tracking dog is actively tracking his prey, his body reacts based on instinct and breed-specific physical characteristics.
Depending on the animal’s sense of smell, the animal’s head may be high or low to the ground. Environmental variables also have a role, although a cold-nosed (poor smell) dog will often keep a higher head position than his contemporaries. When examining the head of a trailing dog, I feel it necessary to additionally examine the placement of the ears. Are they pointed forward, set back along the sides of the head, or widely spaced? Even floppy-eared K-9s such as Bloodhounds, Labs, and other hunting breeds demonstrate considerable variances in-ear set, but these distinctions are not as pronounced as they are in pointy-eared breeds.
When monitoring head position, handlers frequently misinterpret the dog’s mouth position. How wide is the mouth, and what does the tongue do? Typically, the dog’s lips will be slightly open to completely close so that he may utilize his nose and pick up scent most effectively.
I have observed that there is no predetermined tail location for trailing. Commonly, a dog’s tail is held out and erect, although many tails droop, swing to the side, or wag continuously. The most crucial thing to remember is the position of your dog’s tail when he is vigorously pursuing prey. Unless there is an injury or some other issue, this position will remain mostly unchanged.
How the dog proceeds along the smell trail are the final bodily action to evaluate. Some K-9s have a tendency to enter and exit the scent trail. I’ve seen that Malinois are significantly more susceptible than any other breed. It seems proportional to speed and a general impatience to locate the quarry.
A competent manager will store in memory all of these subtle body language indications for future use. It is acceptable to presume that the dog is actively tracking if the dog’s head, tail, and body language stay unchanged. A change in any or all characteristics indicates a break in the scent trail.
Few dogs will instantly halt when a new smell is detected; instead, they will continue in the old route. As the smell cone evaporates, a dog often pauses or begins to quarter into the wind in an effort to reposition the odor. The issue here is the length and width of the fragrance cone. In rare instances, human stink may have extended hundreds of yards beyond the quarry’s initial track or maybe around a curve. This is especially true on expansive, hard surfaces like parking lots and city streets. If the handler fails to recognize a tiny shift in the dog’s body language when the trail is overshot or the turn is passed, the dog may lose the real trail and never recover it again. Nonetheless, if the handler recognizes the body language signs as they are exhibited, he or she will be far better prepared to move the trail and cast the dog.
I have seen that the majority of trailing dog teams suffer from a lack of handler comprehension of distraction behavior. Distraction behavior refers to any K-9 conduct apart from trailing behavior or body language. This behavior is stimulated by odor and sound. Most handlers confuse distracting smell behavior with trailing behavior, making scent the most difficult to manage. In other words, the majority of handlers cannot distinguish if their dogs are following a person or another dog. The trail may begin by following the person, but even the finest tracking dog will frequently deviate to something more intriguing, such as another dog or a more exciting human trail.
Most handlers are blind to minor distracting scents that divert their K-9s off their subject trails, and even when they do notice distraction behavior, they are typically hesitant to fix the issue because they are unaware of the nature of the distraction and the original trail’s quality. It is essential that every service-trailing dog have distraction training in which a variety of recognized distractions are encountered. I have devised a distraction training routine with all of my dogs that enables the handler to easily rectify the distraction.
The K-9’s tendency to follow the most recent or nearest path regardless of the presence of a scented object is the second-greatest difficulty in interpreting a tracking dog. The majority of handlers, including myself, will follow a dog that is fixated on an odor when we read it. What occurs when numerous trails departing a single source point are of varying ages? If the dog has not been educated about this possibility, he will always follow the most recent scent. This has caused many in law enforcement to erroneously believe that canines cannot distinguish between human and animal odors, resulting in the reinforcement of simplistic, soft-surface, fresh-scent tracking training methods.
Split-trail training is a training plan that is quite effective in addressing this issue. This is when two parallel paths are built out and the subjects divide at the end. The second element of this training is trail splitting in the beginning. The dog is required to locate the proper person based on the initial odor he detected at the beginning of the route. This training is typically quite effective and simple to do.
The difficulties outlined in this article are only a few of the numerous obstacles a trailing team faces. Trailing is by far the most challenging K-9 discipline for all participants. This is shown by the ease with which dogs lose the scent or pick a distraction. A basic reality is that the majority of urban paths and trails are ineffective unless they are extremely new. This is unfortunate, as a competent trailing dog can typically overcome hurdles through intelligent and gradual training settings.
Almost as ancient as man’s productive use of the canine nose is trailing. Dogs are capable of smell discrimination, can follow scent trails that are several hours old, and can navigate most urban jungles if properly trained. Occasionally, a dog comes along that defies all training and is a natural-born master of trailing. However, such canines are quite uncommon. K-9s, like their owners, rely mostly on muscle memory. We work as we train; if our training is inadequate, so will our work.
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