By Josh Honeycutt
Imagine this, taking 20 years to ‘cull’ an untold number of “inferior” free-range bucks. Burning tags on wild deer you’d likely otherwise pass. And being told that you’ve done good for the local deer herd.
Newsflash — it’s NOT true. Even the most intensive culling efforts on wild whitetails is so diluted that measurable results are virtually non-existent. Even after decades of efforts the minuscule rate of return is not worth the real result. So, to those who’ve spent years believing in the fallacy, you fell for the lie through no fault of your own. This fallacy has been propagated, and in grand fashion, for far too long.
Those who believe they can impact antlers in wild deer herds
by culling inferior bucks are falling for a long-held myth.
Photo by Honeycutt Creative.
To those who are considering implementation, or still believe in the culling concept, I urge caution. It isn’t what you think. There are too many variables that can’t be controlled in wild whitetails. The science has undoubtedly decided that hunters can’t impact genetics by “culling” deer with inferior antlers. “Many (maybe most) hunters do not believe this, but research clearly shows it is true,” said Kip Adams, chief conservation officer for the National Deer Association.
The Fall of the Culling Concept
The culling concept hinges on the idea that hunters can improve the overall average score of mature bucks in the herd by killing (culling) inferior bucks. This action is directly linked to genetics, and the belief that removing inferior antlered animals from the herd will prevent such deer from passing on their genetics. This is in turn will allow bigger, more desirable antlered deer to do the breeding.
Unfortunately, this idea falls flat. Modern science has proven this to be an incapable task and unfillable order for those attempting to manage free-ranging whitetails. Even hunters who manage thousands of acres cannot rely on culling as an effective tool.
Here’s why. There are four primary factors that impact antler growth. These include age, environmental conditions, genetics, and nutrition. “Of these, deer hunters and managers have the ability to impact two (age and nutrition),” Adams said. “Research studies clearly show we can impact antler growth via genetics in captivity, but not in wild deer herds.”
There are numerous reasons for this. The first and foremost is that Does contribute half of their male offsprings’ genetic code. Does also are responsible for feeding, protecting, and otherwise caring for offspring during the first year of life, of which also impact future antler growth.
“Because selection can only be applied to males, the gain or loss in antler size per generation is half of what would be expected if selection could be applied to both sexes,” Anderson said.
“Bucks are responsible for 50% of their son’s DNA, but the doe is also responsible for 50% of it, and she provides all the maternal care,” Adams concurred. “A buck fawn could have the best genetic potential from an antler growth standpoint, but if his mother doesn’t take good care of him, or she’s not healthy enough to provide abundant milk, then his antlers will be far below their potential.”
According to Adams, antler traits aren’t completely heritable from bucks to fawns, and that you cannot predict a buck’s future antler potential by looking at its father’s antlers. Big-antlered bucks can have small-antlered offspring, and vice versa. Cole Anderson, a graduate research assistant for the Caesar Kleberg Wildlife Research Institute at Texas A&M – Kingsville, recently worked on a research study that supported this.
“For me, the most interesting finding has been the incredible variation of antler scores produced by individual sires,” Anderson said. “For example, a single sire produced offspring that ranged from 121 Boone and Crockett (B&C) inches to 206 B&C inches. We estimated the heritability of antler scores to be about 33%. In other words, about a third of the variation in antler scores is due to the genotypes passed from parents to offspring. Age, nutrition, and the environment all interact with the genotype to influence the traits we see.” Other research studies support these findings.
Even if antler genetics were 100% impacted by bucks, and if antler genetics were completely heritable (neither of which are true), there are still many other issues with the culling theory. There’s a high likelihood an “inferior” deer has already bred one or more does by the time you kill it. They’ve already had ample time to pass on their genetics, even at young ages.
“The whitetail’s breeding ecology simply doesn’t allow any buck (big or small) to dominate the gene pool through breeding,” Adams said. “They’re not like elk or Alaskan moose that form harems. Most of the whitetail rut is quick from start to finish, so the majority of does are bred over a relatively short time. This simply doesn’t allow any buck to dominate the breeding in any given area.”
Even prolifically breeding bucks with big antlers will have a hard time siring offspring with big headgear. Most bucks will sire very few fawns that survive any length of time. “Bucks can breed multiple does, and those does may have multiple fetuses, but only a fraction of those will survive to six months of age and be recruited into the fall deer herd,” Adams said. “Then, only a portion of those will live to the following year and grow their first set of antlers.” Still, even fewer grow a second set of antlers, and so on.
Furthermore, land managers who practice culling also shoot the largest-antlered bucks on the landscape. Therefore, even if culling did work (which it doesn’t), you’d be shooting both the smallest and biggest bucks in the herd. You’d be attempting to increase antler score by shooting inferior deer, all while shooting the bigger deer, too. These actions conflict in nature and outcome, and in theory, would work against one another. With that being said, neither are true. Neither culling nor high-grading impacts wild herds.
Another factor is whitetail dispersal rates. More than half of bucks leave their birthlands. Dispersal distances can vary from 0.5 to 30-plus miles. Unless you control vast, unfathomable acreages, it’s unlikely that a giant buck born on your property will remain there. Anderson’s research concurs. “We believe that intensive culling is unlikely to cause genetic change in wild deer, especially free-ranging populations, where dispersal will tend to homogenize populations making it difficult to achieve high enough selection intensity to affect population genetics,” Anderson said.
On top of that, some bucks move great distances from year to year, and even have various seasonal home ranges that can be miles apart. In fact, a recent study by the Mississippi State University Deer Lab is currently tracking a buck that annually migrates 18 miles from one location to another.
And thus, attempting to grow bigger deer by shooting the ugly ones is likened to playing tennis with a baseball bat. You might hit it occasionally, but even if you do, the ball isn’t landing inside the boundary lines.
Having Bigger Free-Range Bucks
Another 15-year-long study by Texas A&M also revealed that culling doesn’t improve overall antler genetics in wild deer. Researchers’ time spent on the Comanche Ranch studying the relationship between culling and antler genetics didn’t produce a measurable increase (or decrease) in overall herd antler scores.
Today, the Commanche Ranch no longer culls bucks to accomplish that. However, they do cull inferior deer to manage population density. In this way, by removing smaller bucks, they make more room for bigger-antlered deer. Even then, it’s a guess at best as to whether this will have a positive impact. It’s all left to chance.
Despite all of this, there are ways land managers can have bigger free-range bucks. And it all goes back to what was mentioned above — the two factors that hunters and land managers can impact.
Age is the most controllable factor. Allowing deer to reach older age classes is the best way to see bigger deer. Deer tend to grow their largest racks between 5½ and 8½ years old, with a typical peak at 6½ or 7½. Unfortunately, this requires those with smaller properties to get neighboring hunters on board with the plan.
Nutrition is the other factor. Supplying better grub is something hunters can do almost immediately. Improving the habitat, and offering more and better food sources, can increase a buck’s antler growth output. Few bucks express their full potential, but better food helps accomplish it.
It’s also possible to lightly impact environmental factors. One way is to trap predators, such as coyotes, which can stress herds. With that being said, this is far too large of a category to effectively control, including disease, injury, soil composition, weather and much more.
Otherwise, if hunters want bigger deer, and aren’t finding them where they currently hunt, it’s time to go elsewhere. Antler genetics can be better in one area versus another. The same is true for age structure, habitat quality, soil composition (think Midwest versus Southeast) and more. But no matter where you are, or where you go, culling will never be the solution in wild whitetails. It never has been, and never will be.
— Josh Honeycutt is an avid whitetail hunter and land manager from Kentucky.