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The Tale of a QDM Club by Dave Edwards
Own Your Own by Virgil Peritts
What Is TSI? by Matt Ross, QDMA
Native vs. Non-Native by Gabriel Karns, M. Colter Chitwood, Chris Moorman, and Dr. Chris DePerno
Oaks For Bucks by Chris Moorman
Deer Season: A Time For Kids by Stephanie Mallory
The Need For Minerals by Brian Murphy, QDMA
Perlitz Ranch Hosts Youth Camp by Kelly Haydel
Timing the Rut With Fawns by Gabriel Karns, M. Colter Chitwood
Ecological Reasons For Hunting by Dr. R. Larry Marchinton and Dr. Karl V. Miller
What percentage of a buck's antler development potential comes from the doe's genes? by Realtree Whitetail Team
Where were the bucks? by Team Realtree
Growths on Deer? by Team Realtree
How Many Teats? by Team Realtree
Why No Oaks? by Team Realtree
Special thanks to:
Quality Deer
Management Association
Whitetail Insider
Fat and Healthy
Many hunters and biologists wonder about the condition of deer herds. Specifically, they are interested in understanding how healthy the deer are at the population level (over- or underpopulated) and at the individual level (healthy or malnourished).
One objective of my master’s project at North Carolina State University is to assess physiological condition of coastal North Carolina white-tailed deer. The study is still underway, so there are no results to report yet, but some of the techniques for identifying the health of individual deer can be applied by hunters, land managers, and biologists anywhere.
The two easiest, most useful methods for estimating individual health are kidney fat and femur marrow fat. These indices can be quantified using scales and calculations and through simple visual inspection, which is good news for hunters in the field.
Kidneys are easy to find and analyze. Hunters who field dress deer will have an easy time locating these organs by finding them BEFORE they remove the internal organs from the body cavity. Begin the field dressing as usual by cutting through the hide and opening the body cavity. Next, find the stomach and simply maneuver it over to one side and look toward the spine. The kidneys will be small and oblong and maybe hidden by a thick layer of fat. If so, then you have already made the physical assessment of your deer--excellent condition! However, if the kidneys are covered with very little fat, then the deer would be graded as “poor” condition (Figure 1). With greater and greater fat coverage, the scale goes to “fair” and then “good,” before finally reaching “excellent” when the kidney is mostly or completely obscured by fat.
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Also, femur marrow fat content is used to indicate physiological condition. Bone marrow is responsible for making new blood and is generally high in fat. Whether you bone out the hams or not, finding the femur in the hindquarter is easy. As in humans, the femur is the leg bone that is connected directly to the pelvis. Once the bone is located and exposed, simply cut it in half (cross-wise) with a saw or limb-loppers. The cut will expose the marrow that is inside the bone. If the marrow is waxy, firm, and white, then the deer is in excellent condition (Figure 2). At the other end of the scale, the marrow will be runny and red (Figure 3).
Fat content in white-tailed deer varies throughout the course of the year, and this variability is related to changing physiological demands. Deer harvested in the fall and winter should (generally) have the highest amount of fat compared to any other time of year. Deer have added fat during the late summer and early fall to prepare for the rigors of winter. Males need the fat stores to get through the breeding season, and females need the fat to sustain gestation and lactation. So, when you are evaluating your deer next fall and you see a lot of fat in the body cavity, under the hide (particularly around the hindquarters), around the kidneys, and in the bone marrow, you should be able to make an educated guess that your deer was healthy.
It is important to understand these visual indices of deer condition are guidelines. There are exceptions to every rule, so not all deer can be accurately judged using only the above methods. However, in the absence of a lab and proper equipment, visually assessing kidney fat and femur marrow fat will give you a start in evaluating the health of your deer.
About the author: M. Colter Chitwood is an M. S. candidate in the Fisheries and Wildlife Sciences Program, Department of Forestry and Environmental Resources, at North Carolina State University.