Deer Vision
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The Science Behind Deer Vision and How It Affects Hunters

Like it or not, deer have many weapons in their arsenal to prevent hunters from getting a harvest opportunity. We all know that a deer's greatest defense is their nose. Science has shown us that deer have 800 times more receptors in their nose than we do. That's a lot! As hunters, we never cut corners when it comes to a whitetail's sense of smell. We wash our gear in odorless detergent, use field spray, hunt the wind, analyze thermals, etc. Why don't we put that same type of caution into staying hidden visually? Wouldn't being able to better blend into our surroundings and avoid being spotted to add one more advantage to our hunting strategy? Hunters and scientists have been trying for decades to figure out exactly how deer view the world, something that's not easy since they can't exactly speak and tell us.

It's an interesting subject from a biological standpoint, as well as from a hunting standpoint. As hunters, the more that we learn about a whitetail deer's vision, the better we can stay hidden from them while hunting. These studies have led to several new and improved camo patterns hitting the market, with claims that their camo has the most advanced technology to prevent being spotted by deer. While some may argue this is just simply a marketing ploy, I find it fascinating and reassuring as a hunter that we are figuring exactly what these sneaky animals of North America see as they walk through the woods each day.

What We Do Know

Deer Vision

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Ungulates, which are hoofed animals such as deer, sheep, elk, etc. have very interesting eyesight that has evolved slowly through the years like most common prey animals. Like most ungulates, scientists now know whitetail deer are dichromatic, which means that they can likely only see the blue and green color spectrum, unlike humans, who can see blue, green and red. This is due to smaller concentration of cone cells within their eyes. Dr. Bradley Cohen, a wildlife biologist, did a study back in 2014 focused entirely on whitetail deer vision. He found that while deer can pick up the blue spectrum very well, they don't pick up on specific details very well. This created a dramatic shift for many camo companies, which prior to that spent lots of time on "sticks and leaves" style patterns with tons of fine detail. But this new research showed that mimicry isn't quite as important as just breaking up your pattern. It seems those old patterns may have been designed more for hunters than the deer!

Thus, the digital age of camo begins. More and more companies are switching over to digital camo patterns, designed to break up your silhouette, to the point the hunter just melds into all the background brush. Essentially there is a macro and micro science to camouflage. The macro patterns of camo should break up your silhouette, and God forbid if you are spotted, the micro patterns should make you seem less predator-like. In our experience, there may be some truth to this science. While wearing these newer, more subtle patterns, we've gotten in those dreaded stare-downs with does that seemed to have a harder time figuring out what they were looking at than they did the stick and leaves variety of camo in the past.

While deer lack a high concentration of cone cells in their eyes, they make up for it with how dense their rod cells are in their retina. In case you've forgotten middle school science, cones are responsible for detecting color in daylight. Rods are light sensitive and affect visual acuity in the dark. Studies show that rods are over a thousand times more sensitive than cones. These rods act as fantastic motion sensors for deer, alerting them to even the slightest bit of movement. Every bowhunter knows the pain of trying to remain undetected as you reach for your bow. Rods are also what can make getting into your treestand in the morning very interesting if there's deer around. If you've ever had a deer start blowing at you in low light or deer pitch blackness and you wondered how on Earth they saw you, it's because of the rods in their eyes.

Due to this intense sensitivity to movement, taking your time getting into the treestand is crucial. Take a few steps and wait. An old deer hunting friend of mine used to tell me it should take me thirty minutes to walk to a treestand that's only 100 yards away. That may seem like an overkill, but it taught me just how great deer are at spotting movement.

Additionally, according to the National Deer Association, scientists have found deer do not have UV light filters in their eyes like we do. That means deer eyes can pick up on ultraviolet light that human vision simply cannot detect. Why does this matter? Well, because many clothing companies use UV brighteners in their clothing, including those who manufacture camo. Many companies have since slowed or stopped the use of these brighteners once they realized it was making their camo light up like a Christmas tree in a whitetail's eyes. Additionally, there have been specialty washes developed to take the brighteners out of clothing, but it's now viewed as a blunder that hunting clothing makers had to deal with for a while!

How Do Deer See Blaze Orange?

Deer Vision

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Many non-hunters are often confused when they see hunters wearing blaze orange. After all, to humans, wearing bright orange in nature is like waving a giant flag saying: "Here I am!" However, due to whitetail deer not being able to see the red color spectrum like the human eye can, it's very likely that deer see orange as just another shade of gray. They are effectively color blind to these shades. This is great news for firearm deer hunters, as it allows them to follow safety guidelines, and not worry about being picked out due to their vibrant appearance. Even knowing this, I always advise hunters during gun season, you should wear some form of camo on your limbs. Just to break up your outline so you're not a solid block of gray. For me, I generally wear a blaze orange vest and ball cap, with my camo underneath. However, you should consult the hunting regulations made by your state or province's wildlife management agency. Some will have rules requiring a certain amount of orange, and some states do not allow blaze orange camo patterns. In recent years, some have taken to allowing blaze pink as an alternative safety color.

Let's face it, whitetail deer have many tools to outsmart us and leave us scratching our heads at the end of every season. We spend so much time worrying about our scent, I think we sometimes can't see the forest for the trees. That makes us disregard the importance of vision in the hunting equation. That's why you should spend a little more time this coming season focusing on how you blend into your surroundings. Don't just climb into a lone maple tree with no cover. Pick a spot that allows you some mobility without being detected, and a setup that looks as natural as possible.

And with all due respect to the old timers who went hunting with street clothes, leave the blue jeans and plaid at home and find a camo pattern that works for you.