Proper Hunting

Tag: deer senses

  • How far can a deer smell?

    How far can a deer smell?

    The sense of smell among members of the deer family is legendary. In fact, it’s hard for humans to grasp. But recent research into the sense of smell of elk and whitetails finally puts some numbers to it.

    How far can a deer smell? They Can Smell You from a Half-Mile away. Researchers at Mississippi State University found that a deer’s sense of smell, like a dog’s, can be anywhere from 500 to 1,000 times more acute than a human’s. Furthermore, scientists say that whitetails have thousands of sensitive receptors in their nostrils, which they use to sort out up to six smells at one time.

    For more than 50 years Leonard Lee Rue III has observed, researched, photographed and written about deer. He has done more to educate the American public and hunters on the ways of the whitetail than anyone.

    How do you defeat the whitetail’s awesome nose? You can’t. You can only stay in the game by playing the wind and practicing good scent control on every hunt.

    You ought to spend as much time as possible on your hunting property year-round, working on the habitat, scouting and hunting. Every day you’re out there, monitor the wind directions at morning, midday and afternoon. Mark the currents on a map or in a journal. Over time you’ll see the common winds that accompany various weather patterns at different times of the year. That is vitally important info because the majority of the trees you pick for stands will be based on the prevailing winds in your area.

    Most hunters focus on where deer will come in on the upwind side of stands. That is surely important, but it is not enough. When picking a tree, you need to determine where to put your wind, and hence your scent, so you’ll alert as few deer as possible. If a mature buck circles in somewhere downwind of your stand and smells you, he might just melt away into the brush. But an ornery old doe might stand out there and blow like crazy, alerting every deer within a half-mile that she smells a rat. Either way your hunt is probably ruined.

    Always try to set up and float your wind over an area that’s not going to see a lot of deer traffic. For example, let your wind scent drift away from your stand and out into a pasture field, or maybe out over a deep creek that deer probably aren’t going to cross. I sometimes set a stand slightly upwind of a steep hill or bluff that deer won’t or can’t walk up on the downwind side.

    Determining the best wind for a stand definitely involves trial and error. You might look at a map or aerial and say, “Okay, a southeast wind will work best there.” But until you go in and sit the stand several times, you don’t really know if a southeast is best or even adequate. You have to study the unique topography of an area because ridges, bluffs, draws and other terrain features can dramatically affect wind direction. You also need to observe the overall deer movement throughout an area as it relates to various common winds.

    Most hunters concentrate on wind direction, but they often neglect wind speed. Big mistake. I have treestands on the tops of ridges that are perfect for high-pressure mornings with little wind. I also have sets in draws and hollows that are just right for strong northwest winds that kick up after a front blows through. I’ve got a great stand on the edge of a small food plot down in a bottom where, if the wind is above 5 mph or so and stays that way throughout the afternoon, I’m OK.

    But if I try to hunt that stand on a dead-calm evening when the wind drops to nil at dusk, the cool thermals start shifting and falling, spreading my scent all over the bottom and messing me up big time. You’ve got to keep all that in mind to beat a buck’s super sniffer.

    Fortunately, we know a lot more than ever about how deer smell. Let’s take a look at four things that give members of the deer family their amazing ability to smell what’s around them.

    The Long Snout

    Members of the deer family and predators need their sense of smell to survive, so they are equipped with far more olfactory receptors than those animals that do not rely on their sense of smell. The long snout creates more room for special nerve cells that receive and interpret smells. It’s estimated that humans have about 5 million of these olfactory receptors, while members of the deer family, including elk and moose, have about 300 million. Bloodhounds have about 220 million.

    The Specialized Brain

    The area of the brain dedicated to interpreting scent is larger in deer than in humans. The drawing of air across all those receptors in the snout sends signals to the primary olfactory cortex, which is in the temporal lobe of the brain.

    Because this part of the brain is larger in animals that use their nose for survival, this creates an ability to interpret the smells that’s added to their ability to pick up all those smells with those 300-million receptors. This would suggest that using a cover scent of any kind would be futile, because a deer can simply sort the smells out.

    A hunter using deer urine to cover his scent smells like a hunter and deer urine to a deer, not just one or the other. While cover scents have little effectiveness, the ability to reduce (not necessarily eliminate) human scent with antibacterial soaps, detergents and sprays, anti-microbial Scent Killer, and carbon is proven science. The science of the deer’s smell would suggest that reducing human odor is worth the trouble, attempting to cover it up is not.

    Smelling in Stereo

    Members of the deer family also have broader lateral nostrils which allow them to detect smells directionally. Moose have the most pronounced application of this. This allows the animals to determine the direction of the source of the smell more readily. This is called “stereo olfaction,” and it allows members of the deer family to more quickly determine the source of danger.

    You may have noticed a deer raise its head as it is smelling the air. The deer is flaring its nostrils while drawing air across the olfactory receptors in its snout. The animal can quickly determine what it’s smelling and the direction it’s coming from.

    They Live by Their Nose

    The fourth thing that helps members of the deer family survive is simply an increased awareness of the smells around them. We humans might not pay much attention to the scents coming in through our nose until it overpowers our other senses. We don’t think about smells much; until someone hands you a child with a dirty diaper, or you walk into a restaurant where they are frying bacon.

    Contrast that to the life of a deer, which is focused on the smells coming through the nose 24-7. The other four senses take a back seat to the importance of smell in their everyday lives. We humans can increase our awareness of the smells around us just by paying attention to them. Have you ever smelled a rutted up buck before you saw him? How about a herd of elk? Using our ability to smell what’s around us is a skill that can be developed. After all, we are predators at heart.

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  • What colors can deer see?

    What colors can deer see?

    Staying hidden is one of the biggest priorities of a hunter. Those who opt to hunt deer know that deer have a remarkable ability to accurately detect and identify even the most subtle smell and slightest sounds.  Given the deer’s sense of smell and hearing, the next question a hunter has is how does a deers eyes work?

    So… what colors can deer see?

    More importantly, what colors can deer see? Deer perceive colors differently from humans. A study conducted in 1992 found out that deer are actually red-green color blind. Without delving too much into the technicalities of nano meters, rods, and cones, it basically means that they can differentiate red from blue, but not from green or orange. It’s not true that they only see in black and white. They still see in color, it’s just that they have difficulty perceiving colors at the end of the spectrum with the longer wavelength, like the red and orange. Their eyes are only sensitive to colors with shorter wavelength, such as blue. They’re also really perceptive of ultraviolet light, an advantage that we, humans, don’t have.

    How deer see vs. humans

    what colors can deer see?

    To elaborate, humans have a trichromatic vision. We have three different types of cone photopigments or specialized photoreceptor cells in our eyes that enables us to perceive color from different parts of the spectrum, may it be short wavelength light (blue), middle wavelength light (green), or long wavelength light (red). But with deer, this isn’t the case. They only have two cone photopigments, what they lack is the one susceptible to long wavelength light. This is why they have difficulty perceiving reds and oranges. With regards to their receptivity to ultraviolet light, this could be attributed to the fact that unlike humans, they do not have a UV filter which blocks 99% of harmful UV from entering our eyes. Without it, our retinas would be damaged by the UV light. It also helps us see things in finer details. Since deer does not have this filter, they can’t see things with much clarity but they can perceive movement much better.

    What NOT to wear/use:

    So if you want to have more chances of getting your trophy buck, try and stay away from wearing anything blue or using UV brightening fabric cleaners. However, if you’re out there thinking wearing a blaze orange outfit is all it will take to get you your kill, then you’re wrong. Deer aren’t dubbed as an anti-predation machine for no reason. If anything, their eyes are just an added layer to their innate security system. It’s not all there is to it. They may be colorblind but their killer instincts and practical biological makeup definitely make up for what they’re lacking. Needless to say, they’re not easy kill. If you want this hunting season to be a success, it’s important that you go out there knowing exactly what you’re up against.

    Deer Security System

    what colors can deer see?

    Deer have various capabilities that make them well-equipped to detect even the most experienced hunters.

    First, their nighttime vision. Deer are more active during the wee hours of the night. In order to survive, their eyes must be more adapted to seeing things in low light. Retinas of mammals have two light sensitive cells called cones or daytime cells and rods or nighttime cells. Cones are responsible for perceiving light and color. On the other hand, rods function in the absence of the light and can only perceive things that are black and white. A deer’s eye has more rods in it than cones, enabling them to see better during nighttime but poorer in daytime. This also limits their capability of seeing colors. They also have a tape-tum at the back of their eye. A tape-tum is a reflective layer that helps their receptor cells bounce the light that they failed to absorb back across the cells, making it possible for them to use the same light twice. Another reason why they can see better when it’s dark is because their pupils are much more wide-set than ours, allowing them to gather more light in lowlight situations.

    Next is their wide field of view. Since their eyes are set wider apart from each other, their peripheral vision is also much higher than humans. Deer have a peripheral vision that ranges from 250 to 270 degrees while human only goes from 160 to 170 degrees. This gives them the ability to pick up the slightest predator movement from their surroundings as long as it’s just below the horizon. So if you want to stay undetected, you’re better off above the ground than on it.

    Let’s not forget their impeccable sense of smell. They possess no less than 297 million olfactory receptors on their nose while humans only have 5 million. In addition, they also have another scent gland located in their mouth called the vomeronasal organ. To further illustrate their capabilities, let’s compare them to a dog. A dog has only 220 million olfactory receptors on their noses and they can already do pretty great things such as: identifying very small traces of chemicals, detect fear, anxiety or other emotions through smelling the pheromones emitted from a person’s glands, even pick up a human scent from a crime scene that’s a week old! Considering the fact that a deer’s olfactory system is 30% more receptive than that of a dog’s, imagine how much stronger their sense of smell actually is. That’s why when hunting, it’s important to make sure that you don’t smell at all. Not only that, you also have to make sure that your stand is free from your odor since they would also be able to pick up your scent from, say the tree that you’re always on.

    Lastly, a deer’s ears are capable of detecting ultra-high-frequency sounds. Human ears can only detect up to 20,000 hertz while deer’s ears can hear frequencies that go from 30,000 hertz and beyond. Their ears are also built in a way that makes it easier to locate a nearby predator. Like tiny satellite dishes, they could rotate their ears towards the origin of the sound. On top of that, they’re also smart enough to distinguish sounds indicating a threat to sounds that doesn’t. They already know what a hunter’s footstep sounds like. To throw them off, try and change the rhythm of your walking. If you feel like they’re noticed you already, stop making any sound or movement for a while.

    How to Defeat the Security System

    With all that being said, it’s not entirely impossible to outsmart a deer. After all, countless hunters have been doing it for years. Below are a few tips and tricks on how to do just that:

    • Sight

    When it comes to their sense of sight, you already know its weaknesses: they can’t see well above the horizon; they have horrible visual acuity; and, of course, the color orange. So, aside from dawning blaze orange camos, the best way to remain unsighted is staying on top of trees or investing on a ground blind. A ground blind is a tent that’s designed to blend well with your hunting ground. This could give you the stealth that you need without taking away the advantages of being on ground. However, remember that when you’re using a ground blind, you have to be more mindful of your movements since deer are good at detecting movements on ground. If you must move, make sure to time your movements when the deer is looking away from your direction.

    • Sound

    As stated earlier, a deer’s ear can rotate towards the direction of a certain movement. So if your quarry has its ears on your direction, it’s over. You’ve been spotted. Your mission is to prevent that from happening. Be more apprehensive of you’re the sounds that you, your gears, or your weapons could be making. If you must make a sound, make sure that you make it when their ears are turned away from you. Avoid gears with metal pieces on it. Since deer are extra sensitive to high frequency sounds, metals clinking against each other might as well be a glaring alarm that screams danger.

    • Smell

    This might be the biggest challenge yet. Just sniffing off your clothes for any significant odor isn’t going to cut it since a deer’s nose is a hundred times more sensitive. A subtle fragrance might already be a red flag to them. Before going on your stand, make sure that you washed your gear and yourself with an odor-free soap. You can also try some scent eliminating spray or olfactory jamming spray available on the market. Another option is using an ozone machine inside your ground blind to cover and neutralize any of your scent.

    A deer might be equipped with state-of-the-art senses. But so are you! A smart hunter is always at an advantage. At the end of the day, it’s not your gear or your blaze orange camo that would fill your tags. It’s your own skills and competency as a hunter. In the woods, you need to use your own head. Your wit and ingenuity would save you. It’s up to you to come up with various techniques and strategies to fill that freezer, or take that next tropy buck!

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