Just how blind is everyone's favorite game?

It's a common question and often something debated between hunters. What exactly is the vision of a deer like? There are common tales that deer can see ultraviolet light, that they can pick out the difference of blaze orange. So what exactly are deer capable of seeing.

First things first, what colors can deer see? For any mammal the eye contains two light sensitive cells, rods and cones. Rods are used for picking up light in low light situations, cones are used for distinguishing color in daylight. It so happens the humans have three types of cones, red, blue and green. These colors make up all the other colors that we are able to see. Deer only have two sets of cones, blue and green. Once more they are unable to distinguish red from green. So that means deer CAN NOT see blaze orange, as they will tend to perceive it as an greenish grey color. This doesn't mean that if you are wearing a blaze orange coat that you will just disappear. They can still see your shape, and so a break up pattern (if legal) is highly recommended.

Why do deer only have two cones? Deer are crepuscular (they are active during dusk/dawn) so they need to be able to see in low light situations. There for they have more rods than humans, and have sacrificed the ability to see red for the ability to see at night. Adding to a deers ability to see at night is the Tapetum lucidum, a shiny mirror like membrane that reflects light and gives eyes a second chance to pick it up. That is why deer's eye glow when a light is shined on them.

Another interesting ability of deer in low light situations is it appears that, yes, they can see UV. Humans have a filter on our eyes that blocks UV from entering it. A study in 1992 by the The University of Georgia found that deer lacked this filter. They do also have a cone to pick up blues, so it would appear that deer can pick up some UV. To what extent? It's not really clear, and it would only seem to be of benefit in low light situations anyway, as in well lit situations the other forms of light would simply wash out the UV light.

Another thing to look at with a deer's vision is how the eyes are set. Deer, like most other grazing animals have eyes that are set on the sides of their heads. This gives them a field a view that is far, far better than ours, in fact they can see about 80-90% of the world around them. Humans, at best, can see about 50% of the world around us. That does mean that deer can literally see things that are behind them. Don't fret, as there is cause for hope.

The reason that humans can see so little of the world is that we've pooled a large amount of our field of view in binocular vision. We are not alone, many predator (dogs, cats) have forward set eyes, and so have extremely good binocular eye site. There reasoning is because if your going to pounce at prey, it's good to be able to judge where the prey is. Or if you happen to be jumping from one branch of a tree to another, you really want to know exactly how far to jump.

So where as humans can only really see half of the world at once, we do have the distinct advantage that we can focus far better on things. With out turning our heads, humans can focus nearly on everything in their field of view. Deer cannot. Deer's depth is only a small fraction of what they see. Their peripheral vision makes up the vast majority of their sight. So, though a deer may see you sitting up in a tree, they will unlikely be able to separate you from the tree unless you move. We have created an image to help illustrate the difference between what a human would see and what a deer would see. (Note: larger image available for down load at the bottom of this page)

So should you go out and purchase some new detergent with out uv brighteners. It's difficult to say, as we don't know to what extent deer can pick up UV. It defiantly wouldn't hurt for low light level situations. I would also look into getting a break up patter for a hunter orange if they are available in your state. However it is important to remember that the best camouflage and being completely hidden from view will do nothing with out good hunting techniques. Just because a deer may not see you doesn't mean he/she won't smell you or hear you.