Sight

Nearly every outdoorsman can agree that a deer's vision is different than that of a human. Scientists have done extensive studies on how deer see the world and their conclusions have driven many of us to adjust our tactics in the field and the products we choose to gain the edge on big game.

Peripheral Vision

A deer is much like other herbivores in respect to it's cornea. The cornea is the front of the eye where light enters to create an image. A deer's cornea is large and allows the maximum amount of light to penetrate.

Inward from the cornea is the pupil which is the opening that regulates the volume of light that reaches the retina. A deer's pupil is oval with the long axis parallel with the horizon. This long axis maximizes the area that each eye can view at any one moment.

Lastly, the location of the eyes on most herbivores are on the sides of their head, allowing a clear path for a full range of vision.

This combination of cornea, pupil and positioning of their eyes allow deer and many other herbivores to have nearly a 350° area of view with the only blind spot being directly behind them. Avoiding detection is a critical element to success.

Color Perception

The retina is the surface that collects the light and processes it into an image that then is interpreted by the brain. The retina consists of two types of cells that can be divided into the inner retinal cells and outer retinal cells.

Outer retinal cells are called photoreceptor cells, they collect all the light and produce an electrical impulse based on the type of light contacting the cell. The two main types of photoreceptor cells are rods and cones. Rods are located throughout the retina and have the highest concentration of cells in the peripheral area.

Deer also have two types of cones which respond to specific wavelengths of light, or color. Cones have special chemicals which allow them to respond to specific wavelengths of light, however a deer's vision is dichromatic, or having the ability to only sense two colors of light. These colors have been determined to be in the blue and green range with some perception of UV waves.

All the elements of a deer's eyesight are designed to help them achieve two things. First, to locate proper food sources in both daylight and at nighttime to maintain a clean bill of health. The second is to quickly locate, identify and respond to predators or dangerous situations in the field.