The more we know about whitetails, the more we realize there’s much yet to learn. Still, some of the recent whitetail research discoveries are truly shocking. This new knowledge will certainly have a profound impact on deer management and deer hunting. It’s this kind of hard work, happening behind the scenes, that is benefitting deer and deer hunters alike.
Last year, we reported on some of the latest findings in the wide world of whitetails. This year, the annual Southeastern Deer Study Group Meeting (SEDSGM) was in Baton Rouge, Louisiana. While at the 46th annual get together, biologists presented dozens of new research project discoveries. Most of these produced at least interesting, and in some cases revolutionary, batches of new whitetail knowledge. These are some of those discoveries.
1. More Bucks Are Siring Fawns Than Previously Believed
Tristan Swartout, a graduate research assistant at the College of Forestry, Wildlife, and Environment at Auburn University’s Auburn University Deer Laboratory, focused on breeding habits of white-tailed deer.
“Our research found that individual deer often mated with individuals of a similar size and age,” Swartout said. “Such as, older does mated with older bucks, or bigger does mated with bigger bucks. This is assortative mating. We also found that this relationship (specifically with body size of mated pairs) became stronger as the age structure in the population matured.
“We also observed that a decent number of bucks successfully mate in a given year,” he continued. “In the past, it was thought that only a select few bucks mated the large majority of does in an area. This appears to not be the case and more bucks are gaining breeding opportunities than previously thought.”
Anderson realized that inside spread measurement is the least heritable trait, with heritability of only 5%. In contrast, tine length is the most heritable trait, with heritability of 49%.
2. Big Bucks Don’t Always Sire Big Bucks
Cole Anderson, a graduate research assistant with the Caesar Kleberg Wildlife Research Institute at Texas A&M University–Kingsville, produced very intriguing data regarding the heritability of antler traits.
“Overall, antler scores are moderately heritable, with heritability estimates typically ranging between 30-40%,” Anderson said. “On average, our large-antlered sires (sires with a Boone and Crockett antler score greater than 176 inches) produced offspring that averaged about 12 B&C inches greater than the population average of 145 4/8 B&C at maturity (5 ½ years old). However, while these offspring were, on average larger than the population, they rarely developed antlers as large or larger than their sire. Overall, 32 of 106 or about 30% of the offspring produced by our large antlered sires—sires with B&C antler scores greater than 176 inches—developed below-average antler scores at 5 ½ years old.”
What’s even more interesting is certain antler traits are more or less heritable. For example, Anderson realized that inside spread measurement is the least heritable trait, with heritability of only 5%. In contrast, tine length is the most heritable trait, with heritability of 49%.
3. Spring Rains Matter for Healthy Fawns
Miranda Hopper, a masters student at the Caesar Kleberg Wildlife Research Institute at Texas A&M University-Kingsville, studied the effects of spring and summer rains in relation to overall fawn health. The findings were quite interesting.
“We found that early growing season (April) rain had the strongest effect on fawn and yearling body mass in October and November,” Hopper said. “Early growing season rain is important because this period occurs in the early phases of vegetation growth, so rainfall is needed during this period to maximize plant productivity. Rainfall affects deer through its direct effect on deer forage. Deer can take advantage of spring rains to build energetic reserves going into late gestation and lactation, which allows them to produce healthier, larger fawns.
“Our results show that the timing when resources become available to deer has an important effect on body condition,” she continued. “For any managers wanting to improve the size of juveniles in their deer herd, the nutrition available to the deer, and particularly pregnant females, will have lasting effects on size of fawns and yearlings. Based on this study, nutrition in the early growing season is the most important period for predicting fawn and yearling body mass in the fall.”
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4. Too Many Cattle Hurts Whitetail Health
Bryan Spencer, a research assistant with the Caesar Kleberg Wildlife Research Institute at Texas A&M University-Kingsville learned from his research that too many cattle has bigger-than-expected effects on wild deer herds.
“It was rather surprising when we learned that antler scores, fall lactation, body weight, and rump fat all showed different responses to cattle stocking and the environment,” Spencer said. “For example, a one-cow-per-100-acre increase in cattle stocking rates reduced antler score approximately 1.5 inches and male body weight approximately 1 pound. While smaller antler scores might negatively impact hunter satisfaction, we should be equally concerned that cattle stocking was reducing body weights and body fat in deer. Greater body weight and fat in deer are often associated with greater adult survival and fawning successes.”
5. Quality Deer Management (QDM) Is Accepted Regionally
Travis Stoakley, a deer lab graduate research assistant at Auburn University’s College of Forestry, Wildlife and Environment, conducted research to see how deer hunters responded to QDM from state to state and region to region.
“This research was the first of its kind to imperially discover that QDM meant something different in the Midwest than it means in the Southeast,” Stoakley said. “At times, we saw dramatic differences in how different regions viewed the facets of QDM. This difference in interpretation is majorly driven by differences in the cultures, traditions, and historic regulations that cornerstone deer hunting in each region. This is important for private landowners, hunting clubs, and wildlife agencies to understand so that management actions aimed at bolstering deer hunter experiences can be tailored to benefit the needs of hunters in a specific area.”
6. Enacting Policy Change in Deer Hunting Takes Public Support
Charles Ruth, a certified wildlife biologist and big game program coordinator with the South Carolina Department of Natural Resources, presented on the significant input and support needed from the public to change deer hunting policies.
“The issue was getting a statewide limit on antlered deer, and a mechanism (such as tags) to aid in enforcement of the limit and all harvested deer,” Ruth said. “Prior to passage of the law (2017), much of South Carolina had no daily or seasonal limit on antlered deer. The takeaways are 1) Changes often are a long time coming. And 2) public outreach and documenting public support for initiatives are very important in getting legislative or regulatory changes in place.”
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7. People Are Helping Agencies Combat CWD
Recently, North Carolina became the 30th destination to harbor the disease. Moriah Boggess, a deer biologist with the Wildlife Management Division of the North Carolina Wildlife Resources Commission, presented on chronic wasting disease (CWD). His purpose? See how deer hunters would respond.
“We first detected CWD in Yadkin County, North Carolina, in March of 2022,” he said. “It’s been very encouraging to see how well hunters show up when a challenge as big as CWD presents itself. Of course, no one wants CWD to be here, but hunters have still risen to the occasion to follow response measures in addressing the disease. The number of deer that hunters brought to us for testing throughout last season shows their willingness to contribute to CWD response. We have found most hunters to be supportive of disease response because they are concerned about the long-term implications of CWD.
“There are many unknowns about the future of CWD,” Boggess continued. “A lot of research is being done on genetic and vaccine solutions, but neither one of those currently present a solution for wild deer. If there are no breakthroughs in the CWD treatment arena, then we can only expect the disease to spread geographically and increase in prevalence everywhere it currently is. It’s our responsibility as hunters and wildlife managers to not give this disease a ride to new areas, which would only make the problem worse.”
8. Weather Continues to Impact Season-to-Season Harvest Totals
Jace Elliott, a state deer biologist with the Iowa Department of Natural Resources, focused on testing pre-existing thoughts regarding weather-related impacts on harvest totals. The consensus—these are impacting deer harvests.
“Based on our model, which estimates how deer harvest is affected by weather conditions, seasons, temperature, rain, and snow are all important predictors of deer harvest during Iowa’s regular firearm seasons,” Elliott said. “Specifically, deer harvest tended to be lower during gun seasons with a lot of rain or snow, and when daily temperatures were higher.
“I was most surprised to see what a strong effect opening day weather conditions had on the season-wide harvest,” he continued. “For instance, when greater than 1 inch of rain fell on opening day, our model estimates an 8% decline in harvest throughout that whole season. On the other hand, when any amount of snow fell on opening day, we estimated a 10% increase in harvest that season. Of course, this phenomenon is likely to be stronger in Iowa, due to our relatively short gun seasons, than in other states with longer seasons.”
All said, there was much more data, statistics, and research presented at the 2023 SEDSGM event. But we can’t cover it all here. Check out their program for more information. And as always keep striving to learn more about America’s greatest resource. I’m sure next year, and years beyond, will produce even more whitetail research discoveries.