Facts and Myths About Deer Antler Genetics

Facts and Myths About Deer Antler Genetics

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Selective deer harvest strategies might seem like good ideas for improving a propertyxe2x80x99s buck potential, but naturexe2x80x99s hard-wired realities tell a different story.

Keri J. Butt

Many years and deer seasons ago, long before camo was cool, and technology and social media took the hunting community by storm, I can recall watching a hunting show where the hosts were discussing how a hunter could get rid of xe2x80x9cinferior deer antler geneticsxe2x80x9d on his or her property. The process, known as xe2x80x9cselective culling,xe2x80x9d seemed simple. The gist of the theory was that if a buckxe2x80x99s antlers were small with undesirable characteristics, the buck should be selectively targeted and removed from the herd, preventing him from passing his lackluster antler genetics on to future generations.

Frankly, the idea sounded a bit illogical; but then, Ixe2x80x99ve always been of the mindset that, ultimately, therexe2x80x99s a much larger hand residing over nature, and we are in no way meant or supposed to look that hand in the eye, much less try and surpass it. These days, the advances in technology and social media have introduced many positive changes for the hunting community. But, from my vantage point, there have also been causes for concern.

In many circles, antlers have nearly become the sole focus of hunting, prompting some wildlife managers to take inventory of their own methods and compare them to that of media personalities. However, what the average hunter sometimes fails to realize is that there are a ton of experts out there. Not only do hunters often set their personal goals according to this xe2x80x9cexpertxe2x80x9d advice, but they forge head-on into practices that may do more harm than good. The difficulty is deciphering between which ones are qualified to hold expert status and which xe2x80x9cexpertsxe2x80x9d are merely self-appointed.

Can We Outwit Mother Nature?

Good intentions aside, will our attempts to manipulate DNA for personal gain by targeting specific bucks have negative implications? What makes us think that we can throw natural selection aside? Perhaps, the perception alone makes us believe that wexe2x80x99re being proactive in the namesake of herd health. Why else would we throw the term xe2x80x9cbuck managementxe2x80x9d around like a handful of loose change?

Myths and Facts About Deer Antler Genetics

Almighty DNA

DNA is a powerful entity. Itxe2x80x99s a web of intricately detailed labyrinths that are essentially responsible for assigning unique traits and characteristics to every living thing. But, the science that encompasses DNA is insanely complex and virtually impossible for the laymen to understand in its full capacity. Perhaps itxe2x80x99s this lack of comprehension that has led us to believe that we are capable of bypassing the authority of deer antler genetics.

At a glance, the prospect of selective culling appears clever. A buck whose antlers arenxe2x80x99t wall-worthy should be extirpated xe2x80x94 plain and simple. After all, the reason a buck presents poor antler quality must be at the hands of imperfect genetics, right? This will tidy up the gene pool, paving the way for bucks with superior antler attributes to do the breeding.

However, wexe2x80x99re talking about wild, free-range deer, and in those populations, the only entity that culling can eliminate or modify, is balance.

The truth is that there is nothing precise surrounding the methodology behind selective culling to improve genetically driven antler potential in a deer herd. More is unknown than there is absolute, and there is a plethora of studies that explain why itxe2x80x99s an impossible feat.

Dr. Steve Ditchkoff, professor at the School of Forestry and Wildlife Sciences at Auburn University, says that using deer antler genetics and management in the same sentence is misleading because 99.9% of the land we manage for deer has no impact on genetics. Only different genetics can be achieved. xe2x80x9cItxe2x80x99s easy to believe that we are influencing genetics through selective harvest, but there are many factors that wildlife managers fail to consider,xe2x80x9d says Ditchkoff. xe2x80x9cYou cannot affect genetics as a hunter, and you cannot influence genetics through selective culling in wild deer populations.xe2x80x9d

xe2x80x9cSometimes, folks tend to take information theyxe2x80x99ve seen and heard, and make up their own set of rules. The problem with this is that sometimes TV personalities give a lack of understanding to the perceptions they put out to the public,xe2x80x9d adds Ditchkoff.

He Got it From His Mama

One of the most overlooked facets when it comes judging the quality of a buckxe2x80x99s rack is the role of the doe. It makes sense why we might think that a buck can only inherit antler traits from his father, but this isnxe2x80x99t so. Not only does the mother influence her sonxe2x80x99s antlers environmentally, but she contributes to them genetically as well. Believe it or not, a doe can have an even greater genetic impact on her sonxe2x80x99s antlers than the sire.

According to Ditchkoff, antlers are genetically determined but environmentally influenced. While genetic distribution is a combined input from both parents, when it comes to environmental persuasions, the doe bears most, if not all, the responsibility. There are several key environmental pressures that can compromise a buckxe2x80x99s antler growth. Some begin in fetal development.

Proper nutrition for all deer is by far the most basic, yet crucial environmental additive. With it, a buckxe2x80x99s antler potential can soar. Without it, antler quality will suffer. The importance of a doe receiving and providing adequate nutrition for herself and her fawns is critical. Great deer antler genetics mean nothing if well-being is compromised.

There are a number of events that can prevent a doe from acquiring sufficient sustenance during pregnancy and beyond. A brutal winter or late spring, especially in the northern regions, can wreak havoc on a pregnant doexe2x80x99s physical condition. During the last few months of pregnancy, fetal growth increases rapidly, requiring a higher caloric intake from a nutritionally sound diet. When a doexe2x80x99s nutritional requirements arenxe2x80x99t met, neither are her fawns. Disease, age and other anomalies can also leave a harmful impression on a doexe2x80x99s physical condition that can transfer to xe2x80x94 and are equally harmful to xe2x80x94 her unborn fawns. Low birth weight and other health problems can result.

After fawns are born, itxe2x80x99s possible that deficiencies endured while in the womb wonxe2x80x99t end there. At the very least, it sets them up for a rough start to life. Improper nutrition can cause a lactating doexe2x80x99s milk production to be low as well as nutritionally deficient. For a buck fawn, regardless how impressive his genetics are, when his nutritional needs arenxe2x80x99t being met, this paints a discouraging outlook for future antler development.

That said, nature has a way of righting itself. When inopportune environmental circumstances inflict shortcomings early in the antler development, with optimal conditions, extraordinary deer antler genetics may shine once again in all their brilliance. Of course, this is if he isnxe2x80x99t culled as a 1.5-year-old spike because someone mistakenly forgot to consider outside probabilities. In the name of xe2x80x9cbuck management,xe2x80x9d the buck of a lifetime, and his genetics, may have unknowingly been eliminated.

The reverse is also true. When you consider the growth cycle of antlers, itxe2x80x99s nothing short of amazing the amount of progress that occurs in only a matter of four months. To achieve optimal antler development, a buck requires a generous supply of nutrient-rich sustenance. During the summer, when food plots are lush and agricultural crops are in full swing, bucks typically have no problem attaining adequate nutrition. A young buck may have lived in a prime environment. But, an extreme circumstance, like the drought of 2012 which plagued most of the country, can have a damaging impact on a buckxe2x80x99s antler development, even a mature buck.

Deer Antler Genetics

But when something catastrophic results in distress to overall health, nature compensates by putting survival at the epicenter of importance, thus forcing antler development into the back seat. As a 3-year-old, due to a negative outside influence, what began as great potential suddenly takes a sharp turn toward inferior. However, when therexe2x80x99s a lack of concern for environmental blows, the buck is eradicated from the herd. And with it goes his contribution to the gene pool. His antlers might have appeared mediocre because of outside factors, but genetics that were unobservable dictated otherwise.

The Unequal Equalities of Deer Antler Genetics

The male is solely responsible for determining the sex of his offspring. But everything else, genetically speaking, an individualxe2x80x99s DNA, is a product of equal components inherited from both parents. This means that regardless of gender, bucks and does receive and contribute antler coding material. Doe fawns receive equal portions of antler-coding DNA from each parent. Buck fawns, however, will typically receive more from one parent or the other.

Ditchkoff advises that one chromosome typically weighs more, and is longer and larger than the other. If the larger chromosome that codes for antler traits belongs to the mother, at conception, her son will inherit more antler coding material from her than the father.

xe2x80x9cTherexe2x80x99s an inability to judge a doexe2x80x99s genetic potential for large antlers in the wild, and therexe2x80x99s no way to control breeding, so itxe2x80x99s insensible to assume a buckxe2x80x99s antler traits only come from the sire.xe2x80x9d

Further, in instances when the antler coding material that resides on larger chromosome produces less desirable antler qualities, this doesnxe2x80x99t mean that a buckxe2x80x99s DNA doesnxe2x80x99t harbor genes that will produce a more favorable outcome in his future offspring. Since we canxe2x80x99t regulate or determine breeding probabilities in wild deer, itxe2x80x99s impossible to predict the interaction-based product of both parentxe2x80x99s DNA.

The xe2x80x9cOtherxe2x80x9d Genetics

According to Ditchkoff, there are other genetics that have nothing to do with antlers. xe2x80x9cFor example, the immune system doesnxe2x80x99t code for antlers, but deflects pathogenic challenges which affect antler characteristics.xe2x80x9d

 While the science is multifaceted, pathogenic impairments can begin on a cellular level.

Many diseases, for example, can be transmitted through birth matter. So, if a doe is the carrier of a disease or some other sort of antagonistic agent that may be transferred via placenta, then itxe2x80x99s plausible that she will impart the responsible pathogen onto her offspring xe2x80x93 either in-utero or through environmental contamination after birth. A disease-causing pathogen of any magnitude can be a hindrance on antler development, as well as quality and length of life. This is just another example of how environmental influences can sway genetic dispositions.  

Tumors and injuries are also illustrations of environmental influences that have no bearing on genetics, but can negatively impact a buckxe2x80x99s rack. A buck may have otherwise donned the antlers of a super star; but if his rack no longer outwardly reflects optimal genetics, he may be targeted. This reiterates that, by not considering environmental dynamics, a superior buck and his DNA could be eliminated.

The Spike Debate

Itxe2x80x99s a widespread notion that if a 1.5-year-old buck presents spikes or forked antlers, then bad deer antler genetics must have made him that way. Therefore, to keep these unpleasing traits from impeding the next generation of bucks, he becomes a cull buck. However, a multitude of prolific studies have concluded that this theory is incorrect.

In a five-year study, conducted by Mickey W. Hellickson, PH.D., and chief wildlife biologist at the King Ranch in South Texas, Hellickson noted that selective breeding experiments with penned deer have documented rapid improvement in antler quality. However, this particular study set out to determine if the same was possible in free-ranging deer populations.

The study took place on a 9,500-acre enclosure with treatment and control areas. Both areas were hunted. Additionally, the treatment area underwent rigorous culling of 1.5-year-old bucks with fewer than six antler points, and 2.5-year-old bucks with less than nine antler points. The areas were monitored by helicopter and spotlight surveys as well as live capture surveys.

The results ended with 165 bucks culled from the treatment area and 106 bucks culled from the control area. The percentage of bucks that qualified as cull bucks never changed over the course of the study.

Hellickson concluded that despite intensive culling practices that were specifically designed to eliminate inferior antler traits, in five years, the antler quality in the 1.5-year-old and 2.5-year-old cull bucks never wavered.

To reiterate, Ditchkoff likes to use his xe2x80x9cYELLOWxe2x80x9d analogy. “YELLOW refers to the combination of genes that a buck has that go toward his antler potential. For instance, a buck has a Y, an E, two L’s, etc. Even if you cull that specific buck, the individual letters are still present in the population. He just had these letters in a particular combination that allowed him to display that potential. There are other bucks and does out there with some of those letters (genes), and others. So, even by culling an individual, you havenxe2x80x99t removed the genes from the populations that made those antlers. Youxe2x80x99ve just removed them from one animal.xe2x80x9d

The Heritability Clause

Heritability lends an important aspect that sides with the mindset that we canxe2x80x99t alter deer antler genetics in wild deer through culling. For an offspring to receive and exhibit a trait from its parents, the trait must be heritable. Meaning that the variations of a specific and observable trait can be attributed to genetic components, rather than environmental ones.

Genotype refers to the genetic makeup of an inheritable trait, like height or eye color (in humans), an offspring receives from its parents. A genotype may or may not be an expression of what you can physically observe. Phenotype, on the other describes an observable, physical expression of a genotype. For the average observer, a phenotype can reflect a conflict between nature and nurture. Is the trait a function of the way the animal was born, or a function of what was learned? Or, can the physical expression thatxe2x80x99s being notated be the result of an environmental impediment? Since wexe2x80x99re talking about genetics in which there are literally millions of combinations and variations xe2x80x94 and that canxe2x80x99t be controlled in the wild xe2x80x94 therexe2x80x99s no way to discern the true answer.

The bottom line is that in wild whitetail populations, itxe2x80x99s impossible to determine heritability and its functions. Therefore, we canxe2x80x99t know what wexe2x80x99re in fact removing or the implications it may have.

Another study, conducted by Harry A. Jacobson, professor emeritus, Mississippi State University, looked at, xe2x80x9cAntler Development and Genetic Relationship.xe2x80x9d

xe2x80x9cCaptive deer demonstrate that heritability of antler traits for yearling bucks are low and that more important than heritability was the significant influence of the dam. The results of these studies argue against the practice of culling spikes for the purpose of genetically improving antler traits.xe2x80x9d

In a separate study by Jacobson that took place from September 1997 through January 2000, 15 fawn and yearling bucks were captured, tagged and released on a 2,300-acre high-fence property. Fourteen of the bucks survived to at least 3 years old, and 12 survived to 4 years or older. The bucks were photographed each year to document antler growth. As yearlings, seven of the bucks were spikes, and six of them had forked antlers. One buck wasnxe2x80x99t photographed until he was 2 years old.

Jacobson concluded that, xe2x80x9cWhile some spikes had smaller antlers than forked antlered yearlings through 3 years of age, by 4 years, there were no apparent differences, and the buck ending up with the most impressive antlers was a spike as a yearling. These results demonstrate the importance, and need for caution, in making management decisions.xe2x80x9d

A study by D.F. Waldron of the Texas Agricultural Experiment Station suggests that, xe2x80x9cVariation in antler traits is partially due to genetics and partially due to the environment. Yearling traits are a predictor of antler traits at maturity. However, because antler traits can be affected by environmental effects, they are an imprecise predictor.xe2x80x9d

Each of these studies, which are only a small tip of the research iceberg, support the idea that the characteristics of a buckxe2x80x99s antlers early on have no indication on their outcome at maturity. It goes to show that predicting genetic potential in free-range deer, based on external observations, is only a mere guess xe2x80x94 and often proves counterproductive.

Collateral Damage

So, what will culling eliminate? The truth is that culling for anything other than to keep herd numbers in check, (which the last time I checked, is otherwise known as hunting), will only adversely affect herd balance and structure. Even by eradicating a mature buck that, according to several yearsxe2x80x99 worth of trail cam pics, has never amounted to greatness in the antler department, youxe2x80x99re also removing something imperative to a healthy deer population: structure and balance.

Ditchkoff explains:

xe2x80x9cEven mature bucks with inferior antlers provide biological and unseen benefits to the herd that we canxe2x80x99t appreciate,xe2x80x9d says Ditchkoff. xe2x80x9cItxe2x80x99s generally assumed that dominant bucks do most of the breeding, but this isnxe2x80x99t always the case. Juvenile males come and leave a property, so there is a constant influx of young bucks, including yearling bucks and sometimes even buck fawns, that will happily breed does. Older males, even those with subpar antlers, lend social stability and breeding structure to the herd. This can help compress the breeding season, which not only makes for a more action-packed rut, but also reduces the number of late-born fawns.xe2x80x9d

Ditchkoff, who is also an avid deer hunter, believes that, xe2x80x9cThe only reason to cull bucks is if you have too many, and I donxe2x80x99t know anyone with that problem! If a deer steps into your shooting lane that gets you pumped up, take the shot. We make hunting too hard. Have fun and let nature do the rest. The notion that we can manipulate antler-coding genetics through culling to suit our agendas is like spitting into the ocean. It may raise sea level, but not by any measurable amount.xe2x80x9d

Ultimately, we must decide for ourselves which side of the culling debate we sit on. However, before we make that judgement call, itxe2x80x99s worth investing a few hours into research. It may provide a new perspective on thoughts wexe2x80x99ve previously entertained.

In the end, itxe2x80x99s not these reasons combined why culling to improve deer antler genetics is impossible. Rather, itxe2x80x99s all these possibilities why it wonxe2x80x99t work.

xe2x80x94 Keri Butt is a longtime D&DH contributor and whitetail hunting fanatic from Illinois.

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