Researchers at the Texas AgriLife Research and Extension Center in Uvalde have developed a more accurate technique than traditional methods for estimating the age of white-tailed bucks. Dr. Susan Cooper, AgriLife Research associate professor and lead investigator for the new age-estimation research, states “Large-antlered deer sell for very high prices, so harvesting a good buck before it reaches its prime or after it begins to decline can represent a significant loss of income to the producer.” She notes that when owners or managers know the true age of harvested deer on their ranch, it improves their ability to predict the age of live deer on that property.
The traditional method for estimating the age of white-tailed deer has been by visual, tooth-wear patterns, and was developed using northern deer and is inaccurate for estimating the age of wild deer in Texas beyond the rough categorizations of young, mature or old according to Dr. Cooper. The new technique also relies on using the animal’s teeth, but involves measuring the width of the dentine — the hard tissue located under the enamel of a tooth — on a specific tooth.
Researchers have determined the first permanent molar would be the tooth which was most likely to show age-related wear patterns. Using digital calipers, they took accurate measurements in millimeters of tooth height, as well as all ridges of white enamel and brown dentine on the tooth from jaw samples of harvested known-age bucks 2.5 to 7.5 years old. Cooper said evaluation of measurement data revealed that only the width of the dentine in the tooth’s cusps, pointed ends of the chewing surface, was related to the age of the deer.
According to Dr. Cooper, the best measurement fit for aging was the width of the dentine, which they gave the value D, in the front cheek-side cusp of the first molar on the right side of the jawbone. Cooper said the only equipment needed for the study were the digital calipers, which can be purchased from major online retailers for as little as $20 each.
Measurements on freshly harvested deer in the field can be taken after cleaning the first bicuspid tooth, on the right jaw, so the dentine width can be measured. To save doing the math, measurements can be compared to a simple chart that has been developed as shown here in the Deer Aging Chart.
This new technique called the AgriLife Dentine Method – of aging deer provides much greater precision in aging harvested deer than the old traditional methods of looking at tooth-wear patterns. Moreover this new aging technique will be of particular interest to ranchers and hunting lease owners who wish to harvest deer at a specific age. More information about this deer aging method can be obtained by contacting Dr. Susan Cooper at 830-278-9151.
