As prey animals, deer have many amazing defense mechanisms for detecting and avoiding predators like us, and one of them is their hearing. We scoured the research from a variety of sources to learn all about deer ears. Listen up as I cover the science of deer hearing, how deer ears work to detect you, and how deer hearing compares to our own.
Built-in Satellite Dishes
I’ve been told I have big ears, a trait I inherited from my late maternal grandfather, and if the superstition is true, they are doomed to continue growing as I age. Luckily, they probably won’t come near the size of a whitetail’s, which are about 10 times larger than ours on average. This gives them an important advantage in collecting and hearing sounds. The size of their ears is the first piece of the puzzle in how they use hearing to stay alive.
Deer have the unique ability to individually rotate their large ears in different directions at the same time. This makes them very good at pinpointing the location of the source of a sound. Have you ever seen a deer pivot one ear to the rear while the other aims forward? This is how they dial in on sound locations.
The combination of these two traits – ear size and independent rotation – lays the framework for their auditory system. This allows them to pick up some sounds we would unlikely be able to hear and locate them with more accuracy than we can.
Do You Hear That?
Sound is simply vibrations in the air that reverberate at either high or low frequencies, also known as pitch. Low frequency sounds like a mature buck grunt are slower moving and travel further in the environment, while higher frequency sounds such as rattling antlers won’t be heard quite as far away.
Deer hear within a broader range of frequencies than we do. A deer’s best hearing range is from 0.25 kHz to 30 kHz while humans max out around 20 kHz according to research at the University of Georgia Deer Lab. This means deer have the ability to hear certain high frequency sounds that humans cannot.
Researchers also found that deer have the best sensitivity to medium frequency sounds between about 4 and 8 kHz. To no surprise, this happens to be where most deer vocalizations fall, so they simply hear best in the ranges they vocalize most, allowing them to easily communicate with one another and separate those particular sounds from others. You should use this to your advantage this season by utilizing grunts and other vocalizations to help bring deer into bow range.
Distinguishing Sound
Do you know that feeling when you’re in a crowded room and there’s just too much going on to focus on a conversation? Well, that happens in the wild, too. Between birds chirping, leaves crunching, wind blowing and twigs breaking, sometimes it can be hard for us hunters to figure out if it’s a deer or something else making all that racket. According to Dr. Karl Miller from the University of Georgia, deer have a much easier time distinguishing individual sounds than we do and are able to separate natural and unnatural sounds to determine if there is a threat.
One time when I was a kid, I fell asleep in the stand with my dad (don’t worry, we always used our harnesses) and was jolted awake as the grunt tube I was holding clanged into every ladder rung as it tumbled to ground. It’s safe to say that any deer nearby were alerted, because that was a very unnatural sound. Deer are accustomed to hearing leaves crunching, branches breaking, and even loud booms so they don’t necessarily perceive them to be much of a threat. But metal clanging together, candy bar wrappers being opened, and your cell phone ringing is not native to the deer woods, and whitetails can differentiate those from the noises they commonly hear.
So, keep this in mind next time you decide to make a move, and consider waiting for a gust of wind or the ruckus of scampering squirrels before you decide to get into the snacks. Remember, gunshots are not hunting pressure; your presence is hunting pressure.
Keep Your Mouth Shut
We’ve all done it. Answered the phone with a faint whisper, had a quiet conversation with a buddy, and even cussed those damn squirrels that won’t stop rustling behind your stand. We think we’re being quiet enough, but research from the Caesar Kleberg Wildlife Research Institute at Texas A&M-Kingsville found that human voices are the scariest sound of all when it comes to spooking deer.
This particular study examined deer behavior in the presence of various predator sounds to see how they would respond. Of all the sounds evaluated, including wolves, coyotes, dogs, cougars and various birds, deer were nearly twice as likely to flee from the sound of human voices than any other large carnivore that commonly prey on deer. That is very telling.
The NDA published a detailed article about this study last year, so I highly encourage you to check that out and see for yourself.
Not So Different, You and I
Unlike vision, deer and human hearing is not all that different. Deer hearing range and sensitivity is similar to humans, but deer have the capability of hearing higher frequency sounds, like a dog whistle, as long as it is loud enough. There is also some overlap in which we both hear best. Again, deer hear the best between 4 and 8 kHz, while humans do from 2 to 5 kHz. Just like deer, humans perceive sound best at the frequencies in which we communicate, and with this overlap it means deer and humans perceive the sounds of both deer vocalizations and the human voice very well.
In fact, Henry E. Heffner and Henry Heffner Jr. found in their Ohio study that the deer audiogram is remarkably similar in shape to that of humans and looks strikingly like the human audiogram simply shifted about two octaves toward higher frequencies. This means that our hearing is extremely comparable except that deer have better hearing at higher frequencies, and we have better hearing at lower frequencies.
Hear Me Out
Deer are a prey species, and they rely heavily on their senses to detect and identify danger. I hope you take some of these neat facts into consideration this deer season and keep in mind that deer behavior is impacted by the sounds they hear and the perceived threat associated with it. Be sure to stay as quiet as possible, minimize unnatural sounds, and use deer vocalizations to your advantage. If you want to learn more about deer senses and how they communicate, be sure to check out our online modules. Be safe and stay quiet!
