By Chris Eberhart
Is it possible to kill a big mature buck without following strict scent control? The answer to that question is a resounding yes. People hit the jackpot every day, and even mature bucks make mistakes. But just like it’s not wise to base your retirement plan on lottery success, you shouldn’t base your hunting on pure chance either. Regular success on mature whitetails means properly using the right tools for success. Scent control is an essential tool, but you must be meticulous with your use and follow through.
Before I get into how to implement strict and careful scent control it is important to understand a little bit about the science of scent, and how animals smell and react with the olfactory world.
Scent itself is reactive molecules in a gaseous state released from both solids and liquids. The released scent molecules are very reactive, and bind with the moist surface area of our nasal cavities. Special scent receptors in our nose then transmit the information to a portion of our brain that analyzes the scent and interprets the odor. The interpretation is both instinctive and learned. Some scents, like rotten meat for instance, we know instinctively that it is something to be cautious of, while other reactions to certain scents are learned over time.
Humans rely far more on their visual capacity than their sense of smell for survival. We have some of the best vision in the entire animal kingdom, at least during daylight (apart from the raptors). Most prey animal rely more on their noses for survival. Evolution has refined their sense of smell. One of the first morphological differences is surface area of the nasal cavity. Humans have about 2 square inches of nasal cavity surface area. By comparison a good hunting dog, a German shorthair for instance, usually has around 34 square inches. Whitetails have about the same nasal cavity surface area. And at the top end of the nasal cavity surface area is the wild boar, which has around 115 square inches. By merely comparing the surface area of the nasal cavity of various animals it should be obvious that animal’s sense of smell is far better than our own. But how much better? Knowing just how much better animals smell will give you a better idea of what you are up against. Based on this simple measurement we can easily calculate that deer have at least 17 times the nasal cavity surface area compared to humans, which suggests they can at least smell 17 times better than we can. This suggests that if we can smell a certain level of scent from 10 yards a deer experience the same amount of scent form a distance of 170 yards. That is a big advantage already, but it gets even better. Humans have relatively few scent receptor cells per square millimeter in their noses. Deer with about 50,0000 per square millimeter have about 5 times more than humans. So now deer have 17 times more surface are with 5 time more scent receptor cells. If we multiply those two together we now come up with a number that suggests that deer detect scent 85 times better than humans. This certainly isn’t direct math, but just as general guideline it’s at least like this: the things we can smell from ten yards away a deer can smell from 850 yards. And if that isn’t bad enough, prey animals dedicate larger portions of their brains for scent analysis than do humans. It is unknown just how much this increases scent detection ability, but it is probably a multiplier similar to the amount of scent detector cells. Take that 85 times better smelling ability and multiply it again by 5 and you come up with 425. Though this is a speculation on my part because there is no way to truly measure brain processing capacity of deer, but it is reasonable to assume that deer detect scent, at a minimum, 425 times better than we can. And in fact studies on foxes have shown that male foxes can detect estrous females under the right conditions up to 2.5 miles away. Deer probably can do the same.
That was a round about way to point out the obvious: whitetails sense of smell is incredible. We all knew that right? Indeed, we do all know that, but the point is to show just how careful you have to be with your scent control if you want to do everything in your power to beat a mature buck’s nose. Despite all the naysayers out there it is possible, especially with scent eliminating technology at our disposal.
The next stop is to understand how deer perceive their world. The best way to understand a deer’s sense of smell is to compare it to something we understand, our own vision. Humans color vision is spectacular, which is why we focus so much on visual camouflage, which actually when compared to scent control isn’t very important. We can easily detect a single red leaf or piece of paper (see photo above) in a complete forest of countless colors and shades of greens, browns, blacks, yellows, etc. When we actually notice the red leaf we can still see it from an incredible distance, in fact it is almost impossible not to see. If someone attempted to camouflage the red leaf by hanging a bunch of yellow leaves all around, or blue, or green, we would still be able to see that single red leaf. This is how deer smell. They smell a particular scent and can differentiate it from thousands of others at the same time. So no matter what you do to cover your scent, say with fox urine, deer still smell you and the fox urine and a thousand other things. Sorting out which scent is which is no problem for deer.
If, however, that red leaf suddenly shrunk to the size of a quarter (see above) we might walk right by it without noticing. Even if we do notice a tiny red spot, we might not consider it a threat. The situation with scent is similar. If we can reduce our scent to an absolute minimum (there is no such thing as total scent elimination) deer may not detect us at all, or, the more likely situation is that they may not perceive us as a threat. Understanding this is critical to regular success on mature whitetails, and critical to the Eberhart Way of Bowhunting.
My next post will be about how this affects your hunting, the science of beating a deer’s fantastic sense of smell, and the steps you should take to hunt as scent free as possible.