Solving Mature Buck Mysteries

While bowhunters rarely agree on much, few disagree that something magical occurs when a whitetail buck reaches 4.5 years of age. Sure, their antlers are typically larger than the previous year, but I’m referring to other changes which make them significantly more difficult to harvest, especially with stick and string.

Some say that once bucks reach 4.5 years old they become more nocturnal, others say they become “smarter,” and still others contend they are nearly “unkillable”, except during the rut. In fact, if not for modern game cameras, few hunters would believe these bucks even exist in their hunting areas. These bucks would be relegated to ghost stories and old wives’ tales.

Despite the widespread agreement regarding the difficulties of harvesting mature bucks, the reasons for this remain widely debated. So, let’s examine the Whitetail Science and see if we can improve our odds of collecting some bone from a mature buck this fall.

Super Senses

Without question, a whitetail’s senses make it an extremely challenging game animal. But, have you ever wondered why it is equipped with such good senses? It’s simple, for the past 4 million years the whitetail has had to elude numerous predators which enjoyed dining on venison as much as me.

Their senses are highly specialized for this purpose. First, their sense of smell ranks among the best of all land mammals. Under good conditions, whitetails can detect humans and other predators several hundred yards away, a distinct advantage from an escape standpoint. Second, through their large and rotating ears, they are highly adept at detecting and locating sounds of potential danger in their environment. Third, their widely-spaced eyes enable them to detect movement across a 310-degree field of view. Their eyes also are highly adapted to low-light conditions, enabling them to move and feed at night, thereby reducing their chances of becoming a snack for a daytime predator.

Specialized Behaviors

A whitetail’s behavior also is highly adapted to avoiding predators. Their feeding strategy is based on sneaking into the open, consuming as much forage as quickly as possible, and retreating to cover. Once there, they bed and “masticate” – swallow, regurgitate and re-chew their food so it can be processed by their rumen (stomach).

Research by Dr. Mickey Hellickson in South Texas revealed other interesting behaviors of mature bucks. Over three years, Dr. Hellickson collected 470,000 one-minute locations of 43 bucks outfitted with motion sensors that revealed if the bucks were active (feeding, walking, etc.) or inactive (bedded, standing, etc.). Surprisingly, during the course of a year, bucks were active only 43 percent of the time. In other words, nearly 60 percent of the time, bucks were not moving. During the hunting season, there were two primary activity periods – 7:00 to 9:00 AM and 6:00 to 10:00 PM. This reinforces why whitetails are considered “crepuscular,” or most active at dawn and dusk.

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Research by Dr. Dave Hewitt at Texas A&M-Kingsville revealed significant variation in home range size and activity patterns among individual bucks. While the study is ongoing, early results suggest no strong correlation between age and home range size. In other words, some bucks are “homebodies” and some are “wanderers” regardless of their age. They also discovered that some bucks are four times more active than others. However, those which were most active didn’t necessarily have the largest home ranges. They were simply more active within their existing home range, regardless of its size.

Whitetails also are highly in-tune with their environment and sensitive to human intrusion. Research by James Tomberlin and others in Maryland suggests that some bucks have the ability to “pattern” permanent hunting stands. Using GPS radio-collars, they monitored movements of numerous adult bucks throughout the hunting season. While several bucks regularly avoided permanent hunting stands, some occasionally made mistakes and were harvested by hunters. One mature buck, however, never passed within shotgun range of a permanent stand in daylight hours during the entire hunting season. However, after dark, this buck frequented many of these same stand locations.

Despite numerous studies of wild bucks, there is no clear evidence yet that bucks become more nocturnal with age. Certainly, bucks of all ages may reduce daytime movements in response to increased human activity. Equally surprising, studies to date have not supported the claim that bucks are more active at night during a full moon or more active in daylight during a new (dark) moon. All studies reveal the same two primary driving forces regarding deer behavior – their need to feed and their need to breed.

Sheer Scarcity

Despite the whitetail’s highly evolved senses and predator avoidance strategies, the number one reason mature bucks are so difficult to harvest is their sheer scarcity. Throughout the whitetail’s range, the percentage of bucks 4.5 years old or older in most populations is less than 5 percent. So, simple odds dictate that most hunters observe numerous deer before crossing paths with a single mature buck.

Luckily, increasing numbers of hunters are implementing Quality Deer Management (QDM) guidelines on their hunting properties, and the number of mature bucks is increasing. In fact, due largely to volunteer participation in QDM, the number of mature bucks harvested each year has steadily increased during the past decade.

Putting it All Together

Clearly, there are many reasons why mature whitetail bucks represent such a difficult hunting challenge. So, how can we use Whitetail Science to give us the upper hand this hunting season? When it comes to combating a whitetail’s senses, it’s really “back to the basics.” Minimize human scent, watch the wind, avoid making unnatural sounds and minimize movement. Apart from their sense of smell, their other senses aren’t much better than ours. But, whitetails are much more in-tune with their surroundings, as we would be if our life depended on it on a daily basis.

You also can use a deer’s behavioral patterns to your advantage. Recognizing that some bucks are far more active than others, frequent sightings of a buck, especially at multiple locations, suggest he is one of the active ones. This is both good and bad. If it’s a young buck with good potential, it is a great one to pass because the chances are pretty good he will be equally active and visible the following season. However, being active, he also is more likely to be harvested by another hunter. In contrast, a buck that is seldom seen or even photographed at night is likely to be less active and will be more difficult to harvest. Bucks like this also are more likely to reach full maturity given their “shy” nature.

While many hunters don’t need the Maryland study to convince them that some bucks can pattern frequently-hunted areas, it’s surprising how many hunters continue to hunt the same stands and use the same access routes over and over. Whenever possible, avoid permanent stands altogether and rotate other hunting locations as well as entry and exit points. Simply put, besides paying close attention to the wind, be random, not predictable in your hunting approach.

When it comes to overcoming the largest obstacle in harvesting mature bucks, their sheer scarcity, management is the key. Many of you are probably thinking, “Sure, that’s great for those with large properties, but I only hunt a small tract, and my neighbors adhere to the ‘if it’s brown it’s down’ mantra.” Don’t give up, hunters throughout North America are joining forces with their neighbors and forming QDM Cooperatives, and the results are impressive. If you would like more information on QDM or QDM-Cooperatives, contact the Quality Deer Management Association at www.QDMA.com or 800-209-3337.

So, are mature bucks really smart or unkillable? I don’t think so. Certainly, they are an extremely well-equipped prey animal with highly developed strategies to avoid predators. As good friend and mentor Dr. R. Larry Marchinton once stated, ”The prey needs the predator just as much as the predator needs the prey.” One without the other causes both to be less wild, less natural, less than they should be.

In the absence of large predators in most areas, hunters provide a critical role in maintaining, possibly accelerating, the wildness in our beloved whitetail. This also maintains the wildness in the human soul, connecting us to nature in an intimate and spiritual way that only hunters can comprehend. It’s the perfect balance for both the hunter and the hunted.

Brian Murphy is a wildlife biologist and CEO of the Quality Deer Management Association (www.QDMA.com). He also has been an avid bowhunter for the past 30 years.