Deer Dynamics: Casting and Hierarchy

As bucks lose their antlers, both sexes reform the bonds that carry them through the spring and summer.

Tommy Kirkland

February 24, 2010 at 10:35 am  | Mobile Reader | Pring this storyPrint 

Although bucks are highly aggressive during the rut, they periodically engage in conflict throughout the offseason. Once two mature males of equal status clash, they may battle for dominance through the act of “flailing.”
TOMMY KIRKLAND
Although bucks are highly aggressive during the rut, they periodically engage in conflict throughout the offseason. Once two mature males of equal status clash, they may battle for dominance through the act of “flailing.”
The rut has come and gone. Bucks that survived hunting season are dropping their battered racks. Though the whitetails are no longer at war for dominance, the competitiveness still exists — even in the off season.

Bucks that didn’t go to the freezer and were able to evade predators, disease and injury are finally shedding their antlers. However, there can be variations as to when bucks begin to lose their racks.

Typically, most mature males here in South Carolina shed antlers anywhere during January and February; yet some can maintain the headgear on into March and even April.

However, if harsh cold weather sets in early in the Upstate area, and if nutrition is lacking— particularly from a scarce acorn crop — mountain bucks will shed antlers earlier than normal. Bucks in the Midlands and Lowcountry, which are usually under less stress, may tend to keep their racks longer if drought isn’t affecting nutrition.

Known as casting, biologists believe that antler shedding takes place when a buck’s testosterone diminishes — especially due to all the relentless physical exertion of the rut and the demands to procreate. Mature bucks generally drop their racks first; younger, immature bucks keep their antlers longer.

Whitetails in the upper Midwest and New England experience more stress than southern deer; therefore, northern bucks usually antler-cast in December. Also, the animal’s overall health plays a role in determining when casting occurs. The extent of the rut has influence as well.

Simply, the harder and more intense the rut, the more likely it is that mature bucks will shed earlier in comparison to sluggish ruts.

Another factor impacting antler shedding is “predator stress.” Whitetails that are periodically evading coyotes are depleting energy, which induces stress on their metabolism. Here, along with other physical realities, the headgear can drop off earlier than expected. Simply, the level of a buck’s testosterone, stress, nutrition, weather and the geographical region dictates when bucks shed their antlers.

While it is extremely rare, a buck may shed both antlers at the same time. More commonly, one will fall off, leaving the other antler to drop later. A small amount of blood may appear on the ground after the antler drops off, and the pedicel (the pit in the head) will appear red or raw for a few days. The shed antler left on the ground contains calcium and phosphorus, and is coveted by other wildlife for the mineral content.

After the season, hunting for antlers has become a popular pursuit. It’s a good time to survey the land and actually take note of bruisers not taken. However, it’s wise to use caution, mask your scent and not overly intrude their turf.

Some areas to search are feeding locales, travel corridors and funnels, edges, fencerows, creek crossings and near bedding sites.

One may not have had the opportunity to bag a particular buck for the venison, but at least part of a trophy is accessible in the thrill of shed hunting. Also, while one surveys the land for antler sheds, there’s opportunity to observe the reformation of whitetail hierarchy.

For the most part, late winter and early spring is the time for whitetails to socially reorganize themselves from the rigors of the rut. Antlerless bucks congregate and are separate from the females — with the exception of when limited food, extreme weather or predators force both sexes into close proximity.

Bucks that were instinctively witty enough to avoid the freezer will restructure their social bonds they maintained back in the summer months. Through scent communication, these deer recognize one another as homing abilities draw them back to their old feeding and bedding sites. Bucks that were together before the rut will maintain those relationships if undisturbed. Yet there are also loner bucks that stay isolated, and these particular bucks can be difficult to locate and assess.

Bucks are still on edge at this time — not only from winding down from the rut, but an instinctive hierarchy is in effect. Though not near as intense as the rut, bucks during this time can still display a host of body posturing and aggressive vocalizations. Though most mature bucks are antlerless at this time and testosterone levels are rapidly declining, their interactions will still reveal the top dogs.

Just like behaviors seen during the rut, bucks still display their struggle for dominance through bristled fur, ears folded back and circular moves with “sidling” (tilting the body or swaying at an angle while moving toward another deer). Occasionally, they will stand upright and fight with their sharp front hooves — resembling two boxers contending for a prize belt. This is known as flailing.

So even with the post-rut over, whitetail bucks are still in a carousel for dominance. This works to maintain a hierarchy that, in time, cumulates into the rut once again.

Bucks congregating into bachelor groups also allows hunters, through the use of trail cams and old-fashioned scouting, to assess the number and age structures in a given area. In general, bucks usually hang together in groups of three to six — consisting of one or two mature bucks and the rest being 2½ to 3½ years old. But sometimes only two or three bucks form this important deer hierarchy.

As for female deer, they too also work even a stricter bond of socialization. First there is the old matriarch female, otherwise known as the “alpha doe.” She is the dominant one, and can be distinguished by assertive body gestures she inflicts on all the other deer.

The alpha doe is usually the one that is constantly on alert and is quick to warn the herd of danger with a swift loud snort or a slow steady front leg hoof stomp. She is almost always the sentinel for the herd, accompanied by one or more of her daughters and their offspring.

The alpha doe teaches the younger deer all the basics for survival within a given home range. This area may fluctuate from time to time in the South, but is usually anywhere from 60 to 500 acres depending on nutrition, water and cover. Her commands and instinctive dictates of socialization are crucial for survival — especially when it comes to predators.

For example, if coyotes run the deer during the night and the whitetails are forced to separate, then the matriarch’s guidance kicks in. Even without a scent trail to locate one another, the younger females are still able to regroup as day breaks and the coyotes retreat. Simply, the herd returns to familiar feeding and bedding sites — a learned habit due to a strong bond and the matriarch’s dominance to guide the herd.

It’s this structure of herd hierarchy that not only keeps order but contributes to young-buck dispersal to maintain procreation and minimize inbreeding. The alpha doe can drive off young bucks.

Good herd health, nutritious habitat and the proper age and social structures of whitetails requires a sound hunting and management program. Though controversial, antlerless harvest is one approach to achieve healthy and diverse whitetails. Also, controlling high female densities prevents the habitat from being overbrowsed.

Basically, the Quality Deer Management Association methods stress to periodically remove a certain number of females, while allowing young bucks the opportunity to grow and reach maturity. Of course, determining the carrying capacity (number of deer a particular locale can biologically maintain without adversely affecting other plants and wildlife) is crucial for assessing a proper doe harvest. This can be a daunting task, especially within the understory of swamps.

Harvest programs must be evaluated with the number of deer per square mile as well as buck-to-doe ratios and buck age structures. Once a census of deer has been determined, then a hunting agenda can be pursued. Some years may require a liberal doe harvest, while other years may need a more conservative approach — especially if predators are adversely affecting fawn recruitment.

As for buck management, it all depends on one’s objective through traditional, quality or trophy deer management. A combination of these programs can also be implemented depending on fluctuations from year to year.

State regulations, particularly antler restrictions, will ultimately dictate what one can or cannot do. Overall, although there is controversy between these three basic deer management programs, most state agencies managing public lands as well as private landowners are now attempting to practice sound programs that benefit hunters afield, the habitat and the deer as well.

The whitetail’s social hierarchy is vital not only for procreation but survival in evading predators. Today, hunters are encountering more and more predators afield and are primarily concerned about fawn predation — the topic for next month.

Antler shed hunting is becoming a popular pursuit after the season. Sheds can be located in or near prime winter feeding areas, fencerows, creek crossings, common travel corridors and funnels.
The typical doe herd consists of an alpha doe (matriarch) and her offspring and their daughters as well. The alpha female is recognized not only by her size and age, but her assertive behavior to show dominance.
Fresh blood stains on the pedicels, located on the forehead, indicate a buck just after an antler shed. The blood quickly dries and forms a scab.
The social structure among groups of bucks and does helps determine the makeup of a localized herd.
 





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