Years ago as a doctoral student at the University of Georgia’s Deer Lab, Gino D’Angelo put whitetails in a sound-testing booth and monitored their brainwaves to see how the animals responded to different sounds and frequencies. (Dr. D’Angelo is now is an Assistant Professor of Deer Ecology and Management at UGA’s Warnell School of Forestry and Natural Resources.)
Here are 4 things Dr. D’Angelo and his colleagues found about the whitetail’s sense of hearing:
Deer do not hear that much better than we do! The frequency of sound is measured in hertz. Studies have found that a healthy human can hear from 20 to 20,000 hertz, with our best and most sensitive range from 2,000 to 5,000 hertz. The researchers found that deer hear best at moderate frequencies of 3,000 to 8,000 hertz. To put perspective on it, both our normal speech and most deer vocalizations fall within these frequency ranges. So while deer generally vocalize at lower frequencies than we talk, they hear similarly.
Low-frequency sounds travel farther and can be heard better by deer at greater distances than high-frequency sounds. A good example is a hunter walking in the woods, crunching leaves. Deer can hear that, so go slow and carefully and step as quietly as you can. Human speech is a moderate frequency sound that is well within the peak hearing range of deer. Talk softly and whisper in the woods. As Dr. D’Angelo says, “The deer are listening.”
How deer use their ears makes us think the animals can hear a lot better than we can. Deer ears are like tiny satellite dishes that tip back and forth and roll around to pick up, sort out and lock in on various sounds in the woods. Think about this, because you’ve probably been there. A buck is within 100 yards and hears you bang your bow or gun, or scrape your boots on a metal platform; you watch him work his ears, look your way and start stamping his foot. Wow, those ears are amazing and almost supernatural, you think. But Dr. D’Angelo points out that the animal is simply reacting to a strange and potentially dangerous sound in his environment, in much the same way that we jump and look if we hear a sudden horn or a car backfire nearby.
The sounds and frequencies of grunt calls match well with the whitetail’s hearing. As an off-shoot of this study, the researchers analyzed several brands of grunt calls to see how they aligned with the hearing of deer. All the calls produced similar sounds with the strongest frequency range between 3,000 and 4,000 hertz—well in tune for a doe or buck to hear your grunts.
Dr. D’Angelo points out that while your grunt call sounds true and is well tuned to a deer’s hearing, it is not as loud as you think. So if you’re “calling blind” with no deer in sight, don’t be afraid to grunt loudly, especially during the rut. There’s a good chance that somewhere out there in the woods an old 8-pointer will roll his ears and home in on your stand. Keep grunting and with luck he’ll come.