Bob Humphrey is the Biology & Deer Behavior field editor for Buckmasters Whitetail Magazine and holds similar titles with other major hunting publications.
He currently lives in Maine with his wife and two children. For more information about Bob, visit his website at www.bobhumphrey.com.
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Jousting with one antler:
No need to cull Spike on One Side (SOS or SOOS) deer. Researchers assign pedicle or early skull trauma as root causes of the phenomenon, not genetics.
QUESTION: Two years ago we noticed some type of defect within our deer population when a guest shot a buck that had antler growth on only one side. The other side had nothing, not even a nub, just skin. Since then we have taken several more and I have trail cam pictures of others. How do we determine if this is being passed along by the doe or buck? — Charlie H.
ANSWER: Your situation is quite unusual, and I’m afraid I don’t have much to offer in the way of an explanation. Perhaps some background on a slightly different occurrence will help.
I ran into a somewhat similar malady several years ago in Mississippi when I harvested two bucks with spikes on one side. I contacted Mississippi Department of Wildlife, Fisheries, & Parks deer biologist William McKinley, who directed me to research being conducted by Gabe Karns from Auburn University.
Karns was exploring the phenomenon of “spike-on-one-side” (SOS or SOOS) bucks, and whether they reflected inferior genetics and should be considered cull bucks. From a sample size of 71 SOS bucks he was able to assign “probable cause” to 44, 34 of which were the result of pedicle or skull trauma (likely due to fighting). Because of the sample collection protocol, he couldn’t determine if other cases may have been the result of healed leg fractures, old gunshot wounds or other skeletal injuries, though previous research indicates that as a likely cause.
Karns noted any damage to the pedicle, including antlers that failed to cleanly separate from the pedicles when shed, can negatively affect antler development.
“It is well documented that antler deformities due to skeletal injuries progressively disappear with each subsequent antler growth cycle, meaning you can expect most SOOS yearling bucks to develop normal antlers in another year or two,” he said.
He also suggested an increasing likelihood of injury with increasing buck age as a likely cause of SOS on older bucks. “Let’s be clear about one thing,” he said. “Harvesting SOOS bucks does nothing to improve the genetic quality of a deer population. Hopefully, this research will hammer another nail in the coffin of the mythical genetic cull buck.”