A Deer's Nose Knows
Reprinted from my Know Whitetails column in a 2007 issue of Whitetail Journal and also found in my "Advantage Whitetails" book, found elsewhere in this website.
It�s a familiar story. I walked into my tree stand before daylight one cold November morning and saw a few deer, but nothing close enough to shoot. I left the stand at noon, and hunted elsewhere that evening and the next morning. The following evening I returned, and due to the prevailing wind, I took a different route to get to the stand.
Just before dark a really good buck was headed my way. The wind was perfect, but at seventy yards, he stopped, lifted his head high, turned and trotted away. As darkness fell, I checked out the spot and realized that he had just intersected the path I walked in on the day before. Gotcha Dave. A deer�s nose knows.
Some folks say that a deer can smell 1,000 times better than humans, and others say it is 10,000. With numbers that big, I�m not sure it matters. What is obvious is that a deer survives by its nose and rely on their nose for everything. It warns them of predators, it helps them find food, and it functions in many ways to help deer communicate with one another. One thing we may never fully understand is how their nose works, but some new science gives us some clues. And understanding that will reinforce your efforts to stay scent free.
In 2004 two researchers got the Nobel Prize in Physiology for their work on how humans detect odors. They found that in humans there is a small patch of odor receptor cells inside the nose where proteins are made that allow the detection of different odors. There are genes that code these proteins allowing them to be made. That�s right, smelling is tied to genes. Mice have 1000 or more of these genes, while humans have around 300. We will probably never know how many odor genes and receptor proteins deer have, but almost certainly it is in the thousands.
Each receptor protein can detect one to two or three odors. Thus, for humans, relative to smell, things are very specific. The odor information in these receptor protein cells then goes to the brain where several odors are combined, forming a pattern. Stay with me here, I know this detailed stuff.
To quote the scientific research on odor detection in humans, "we can consciously experience the smell of a lilac flower in the spring and recall this olfactory memory at other times." "A unique odor can trigger distinct memories...." Now let�s assume that deer function the same way in determining odors (which isn�t a stretch because humans and deer are both mammals).
For deer, odors are inhaled and hit the receptor cells in the nose. Genes code the creation of proteins for these odors and they are sent to the brain where patterns are formed. Several different food odors go to the brain, a pattern is formed wherein deer can discern places to go to eat. If a certain odor helps them get to the food plot, then that becomes part of the pattern. But this system can work against hunters. Clothes, tires, gasoline, cigarettes, perspiration, are different odors that deer take in, appropriate proteins are created and that information goes to the brain where a "pattern" is formed ... a pattern that ain�t good for us.
So not only do they smell good --- as proven by that big buck that smelled my tracks a day after I left them --- they can also take in several odors and form a pattern that stays with them forever. Maybe that pattern might involve acorns, dead leaves, and some human-created odor. If a buck ever has a negative human encounter (shot at, chased, etc.) while smelling those odors, then any time in the future, when he takes in those odors, he may just take off. The older the deer, the more negative human-related patterns they have, and when they smell it again, they may never return to that exact location.
That�s because any human�related odor can be learned, stored away in a deer�s brain and be there forever. If deer are around farms, people, with no negative encounters resulting (i.e. no dogs chase them, no hunters, etc.) then the patterns they store won�t result in flight. However, in most deer country, those human-related odors are negative for the deer, and they react, and they remember the odors that elicited the problem forever.
Now, what enhances those odors? One obvious one is weather. We know that deer lick their noses all the time, especially bucks during the rut. Why? Because odor particles stick to a deer�s nose better when it is wet. Then those odors are inhaled and hit the odor receptors and go straight to the brain, where the "pattern" there tells the deer how to react.
OK, so now we know how it works. What can we do to reduce our odor and defeat a deers nose? I suggest you use all the products out there to reduce odor; scent free soaps, deodorants, scent-reducing clothes, scent-reducing sprays, etc. Also do everything you can to keep human-related odors from your body and clothes. Keep your hunting clothes clean, place them in scent-proof bags or containers, put your hunting clothes on outside, don�t get overheated while going to your stand, etc., etc.
Interview the top deer hunters in the country and they will all tell you that controlling your scent and watching the wind is the most important key to successful hunts. This is especially true for bowhunters who have to get close to harvest a deer.
How many times have you heard a hunter say that the best chance for a big buck is the first time they sit a stand. Why is that true? Odor.
Some folks think that deer are smart, and that the older bigger bucks are the smartest. I don�t think intelligence has anything to do with it. Deer aren�t smart. They have great reaction time, and it�s all about odors that have created patterns in their brain. Patterns that they react to in a millisecond. Young bucks hesitate when they see or smell humans. Those patterns are being built, and if they live another year, that hesitation is gone.
There is no doubt about it, you need to take all the steps possible to increase your chances of harvesting a deer because a deer�s nose knows.
Just a little to add.
All Contents � Copyright 2005
Dr. David Samuel