For a long time, it was commonly thought that deer saw the world only in shades of gray. Scientific research now shows that deer do perceive color, though their experience of color differs from that of humans. Understanding these differences provides insight into how deer interact with their surroundings.
How Deer Eyes Work
Deer eyes contain two types of photoreceptor cells: rods and cones. Rods are highly sensitive to light, providing black and white vision in low light. Cones are responsible for color perception and detailed vision in bright light. Deer retinas have a high concentration of rods, allowing them to see well during dawn, dusk, and at night.
Deer have fewer cones than humans, affecting their ability to see fine detail and a full range of colors. Their eyes also feature a reflective layer called the tapetum lucidum. This layer reflects light back through the photoreceptors, increasing light absorption and enhancing their night vision, which is why their eyes appear to glow in the dark when illuminated. Deer eyes are located on the sides of their heads, providing a wide field of view, 300 to 310 degrees, helping them detect movement from various directions.
What Colors Deer See
Deer possess dichromatic vision, with two types of cone cells, unlike humans’ three. This allows deer to perceive colors primarily in the blue and yellow spectrum. They are particularly sensitive to short-wavelength light, including blues and ultraviolet (UV) light, which humans filter out.
In contrast, deer struggle to differentiate between longer-wavelength colors such as reds and oranges. These colors often appear to deer as muted shades of gray or brown, rather than the vibrant hues humans see. For example, what appears as bright orange to a human might look like a dull yellowish-gray to a deer. Deer are considered red-green colorblind, similar to some forms of human color blindness.
Applying This Knowledge
Understanding deer vision has practical implications for outdoor enthusiasts. Because deer are highly sensitive to blue and UV light, wearing clothing that contains these colors, or has been washed with detergents containing UV brighteners, can make a person more visible to deer, especially in low-light conditions. Many commercial hunting garments are designed with patterns that break up the human outline, which is a more significant factor than color alone in concealment.
Despite not seeing red and orange as vivid colors, safety blaze orange remains important for human visibility to other people. To a deer, blaze orange appears as a neutral, muted yellowish-gray, which can blend into natural backgrounds. Focus on minimizing movement and disrupting your silhouette, as deer are highly attuned to motion and changes in contrast within their wide field of view.