A Coyote's Nose
"The Coyote’s Nose
Anyone who has called coyotes has, at some time or another, fallen victim to the coyote’s nose. With cover scents and scent-masking clothing, hunters invariably think with these new wonder tools they can completely thwart a security device millions of years in the making when, in fact, even the very best scent-altering technology serves only to modify how an odor is perceived rather than block it completely. With their use, odors are muted in such a way that rather than being like a slap in the face, the odor’s intensity is more of a tap on the shoulder. The coyote, in our case, still knows that you’re there and where you’re at, but your presence isn’t a punch to the nose.
We should also understand that before we can have any meaningful discussion about how a coyote’s nose functions and how that knowledge can be applied to hunting, we need to acknowledge that a coyote smells differently than we do. In fact, considering the big three senses we use every day, coyotes not only smell differently than we do, but they see and hear differently, too. Furthermore, it’s not enough to say that the only difference between them and us is that they simply smell, see or hear better because it’s much more than that. Their world is different than ours in terms of how they perceive sounds, colors and odors, and to think in any lesser terms is a gross oversimplification of their abilities.
Modern technology has afforded researchers the ability to identify how coyotes perceive their world. We’ve known for years that canines can hear frequencies well above those detectable by human ears, and recent research has proven that they see things differently because of the inability to see certain wavelengths of light (colors) and the fact that the structure of their eyes lends itself to detect movement much better than ours, but not to see detail.
Their sense of smell is no different.
By understanding how their noses are built, what equipment they have buried deep in their noses and how it works, we’re able to develop hunting strategies that better prepare us by knowing what to do to circumvent their defenses, and more importantly, what not to do.
What’s in the snout?
Coyotes are what science-oriented sorts like my friend Rich Higgins of Mesa, Ariz., refer to as “long-snouted canines,” similar in form and function to drug and cadaver dogs. Having spent an obscene amount of time studying everything coyote, Higgins was my go-to man when I wanted to know more. And, according to him, that long snout, or rostrum, contains just enough room to house what amounts to an impressive array of gear designed specifically for smelling stuff.
The rostrum, running from the tip of the nose to just in front of the eyes, can be divided into two identical halves called nasal cavities, which are separated by a thick wall of cartilage and bone called the septum. Within each of the left and right sides of the septum is a vast network of thin, honeycomb-like bones called the ethmoturbinates, all of which set immediately above a bony surface called the subethmoidal shelf, which is the uppermost part of what we lovingly refer to as our palate.
The surface of these turbinate bones is covered with a thin layer of soft tissue with another $10 name called the epithelial mucosa, and buried within this mucosa is the first secret ingredient to the coyote’s famed scenting ability — 250 million nerve endings, each of which is hard-wired directly to the scenting (olfactory) center in the brain. For comparison, our noses have barely 5 million nerve receptors and nowhere near the number of turbinate bones.
While we’re on the subject of this mucosa, let’s not forget the cilia — tiny hairs covering the surface of the mucosa that entrap molecule-sized scent particles as they’re drawn into the nose with each breath. As a coyote inhales, scent particles are brought through the nose and into the turbinates where they are snagged by sticky mucous (snot) on the cilia where they await processing.
With certain odors, the concentration of scent particles is so high that one sniff is enough, such as when kissing close to where a skunk has sprayed. But, how can a coyote detect concentrations of scent particles so small that one sniff just doesn’t seem like enough to get the job done? The answer to that question is the second part of the recipe and has to do with the structural engineering of the nostrils.
Within each nostril, or nare, is a tiny flap of skin that acts like a valve, opening and closing depending upon whether the coyote is breathing in or out. When the coyote inhales sharply or sniffs something, scent-particle-laden air is drawn into the nose, where it is directed down the center-most corridors and over those turbinates. Immediately afterward, when the coyote exhales, that flap of skin closes and redirects exhaled air down different corridors along the outer edges of the nasal cavities.
The purpose for this is that particles being drawn in are entrapped by and deposited on the cilia lining the epithelial mucosa and are protected from being blown right back out by this redirection of exhaled air. With each subsequent sniff — and all of us has seen a dog or coyote sniff something about which they’re curious many times before their curiosity is satisfied — more scent particles are deposited and accumulated, until the concentration of particles is sufficient enough for the nerve endings and brain to identify the scent’s source, allowing coyotes to identify odors in only parts per trillion.
How coyotes use scent
Just as important as how a coyote smells is knowing how they use this information and why. To fully understand and exploit this critical information, we should first discuss a few relatively new concepts to hunting as they apply to coyotes: pressure and security levels.
For as long as we’ve been calling coyotes, we’ve used the term “educated” to refer to coyotes that have presumably been called, shot at and escaped, and because of this experience have become call-shy and difficult to call. As sensible as this line of thinking might sound, it isn’t practical to attribute all call-shy coyotes to a prior exposure with calling because it’s highly unlikely that all call-shy coyotes have had such an experience.
A more accurate term to describe these coyotes is “pressured,” and pressure can come in many more diverse forms. Predator hunters, all other hunters, bird watchers, ATV riders, ranchers and farmers, amongst untold others, put pressure on coyotes through their daily activities that lead them to come into close proximity to coyotes. A coyote doesn’t have to be shot at to feel this pressure. The encounter might result in nothing more than the coyote being temporarily displaced from its resting place, but displaced nonetheless, and intrusions like this take their toll on how secure a coyote feels in its home.
As a coyote endures more of these intrusions and, as a result, more pressure — consider hunting seasons and feeding winter cattle on winter-dormant range as causing profound increases in the number of people in the coyote’s house — their security levels begin to decrease to the point that they become very wary and difficult to approach. At this point, even the slightest trigger puts them into full-blown paranoid mode, which, to most of us, best describes the coyote in its natural state.
After they get to this point, the insecure coyote will then become increasingly dependent on its senses as a form of defense rather than offense alone, especially its sense of smell. As Higgins is fond of saying, “For the coyote, to see is to be deceived, to hear is to be misled, but to smell is to believe.
Witnessing the phenomena
To illustrate this phenomena, Higgins shared with me his experiences when he was invited to take part in a project with Michael Jaeger of the Logan, Utah, Predator Research Center on the Idaho National Lab in Mud Lake, Idaho.
Coyotes that had never been shot at or hunted were outfitted with radio collars that allowed researchers to monitor their location 24 hours a day by satellite. At the end of each six-week study cycle, the coyotes were recaptured, and the information collected was uploaded to computers, where the collected data allowed them to create real-time animations of the coyotes’ activities. Although the coyotes weren’t hunted, these coyotes endured a great deal of pressure from the study researchers, and their behavior clearly demonstrated the effects this pressure had on their security levels, and thus, their willingness and how they approached calling during Higgins’ visit.
“Only two coyotes made a direct approach,” Higgins said. “All others immediately circled straight downwind where they remained throughout the entire stand.
Coyotes have an incredibly sensitive nose.
“I set up all my calling stands on the upwind side of large meadows in the study area, thinking that if a coyote wanted to wind us, it would have to reveal itself.”
All but two of the coyotes ran to the downwind side immediately upon hearing the distress sounds and howls that Higgins offered them while calling, moving through the sagebrush out of sight and undetected.
“One of the meadows we called was more than a half-mile across,” he said. “The target coyotes (being tracked by satellite and computers from the collars they wore) ran at top speed to the downwind side, where they stayed until well after we were finished.”
Another meadow was within a wide bowl.
“The target female used the lip of the bowl to conceal herself as she ran three-quarters of a mile to the downwind side, where she remained for only 15 minutes before continuing at full speed around the bowl to her starting position,” he said.
Higgins’ conclusions based upon what he saw?
“All my stands were made well within established and defended territories,” he said. “I believe that the residents felt compelled to investigate the intrusion within their territory, but their low security levels prohibited a direct approach. Their noses told them what they needed to know, even at very long ranges, while remaining concealed. It makes you think twice about dry stands where sign is present but the coyotes don’t show, doesn’t it?”
Using the information
Equipped with all this new information, how can we change our hunting methods for the better when forced to deal with the wind?
First and foremost, the only way to beat a coyote’s nose is to never allow them to get downwind of you, by their own or by you calling from or passing upwind of their position. But this isn’t always possible.
Second, recognize and appreciate the effects of human intrusion (of all kinds) on coyotes, their security levels and how it affects their willingness to respond to calling.
Third, outfit yourself with the proper gear, and modify your hunting methods to address what you now know about how pressured coyotes respond to calling.
Approach stands quietly so as not to broadcast your presence, and be painstakingly careful to avoid ever being upwind of where you expect coyotes to be when you hunt. This becomes increasingly important as fall and winter progress because of the increased presence of other people in and around where you hunt.
Set up so you have a commanding view of your leeward or downwind side so that you increase your odds of spotting a coyote circling to get your wind. Elevation is always a plus. Understand that “downwind” is not necessarily a straight line. Topography, brush and other structures, thermal currents and a litany of other factors cause air passing over you to move erratically, swirling and eddying until that single narrow column of straight line air has transformed to a broad swath of stink covering areas 45 degrees to either side of that aforementioned straight line.
Consider the benefits of hunting with an electronic caller or partner. In either case, set yourselves up downwind from the source of the sound to take advantage of coyotes that want to circle, thus directing them into your waiting lap.
Also, consider the benefits of misting a mixture of various urines both before and during the stand as a way of confounding and overloading the coyote’s sense of smell. (See “Coyote Nirvana,” January 2004 Trapper & Predator Caller). It won’t buy you time in terms of minutes for the shot, but it will get you seconds when seconds count.
And finally, don’t forget the value of a simple lip squeak or decoy. Although not a silver bullet, decoys and lip squeaking might keep a coyote’s attention focused on what it can hear and see until it enters the kill zone, whereas the sound of silence might compel the coyote to circle before you can get the shot.
Exploit the weaknesses
I’ve always said the best coyote callers spend more time learning about coyotes and less time worrying about learning to call. Knowledge is king, and knowing your coyotes — their behavior, physiology and ecology — are the true secrets to becoming a better coyote hunter.
Every facet of the coyote’s physical being lends itself to survival. Whether it’s the structure of its eyes, ears, hair or nose, function goes hand in hand with form and ultimately, all parts together form what we know as the ultimate prey animal — the coyote.
Despite $10 words that are often hard to spell, let alone say, knowing how a coyote is built and being able to develop and implement calling strategies that exploit their few weaknesses is the key to successfully and consistently calling coyotes.