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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
Timing the Rut With Fawns
Every fall, as deer season approaches, hunters invariably talk about when they should hunt to maximize their chances of tagging a big buck. Much of this talk revolves around the “timing of the rut.” Hunters are taught that during the rut, bucks are more vulnerable because they spend their time searching out receptive females.
The premise of this thinking is correct. However, it seems that many people think that white-tailed deer breeding is limited to a day, or two days, or a week. Although much of the breeding does occur in a “short” time window, hunters might be surprised by the range of time over which all the breeding occurs. Interestingly, the length of the breeding period can be estimated by measuring fetuses and back-calculating for conception date.
Using a ruler that is available from the Quality Deer Management Association’s online store, hunters can measure a fetus in millimeters and use the length to estimate its age. Once the age (in days) is known, the date of breeding can be determined on the back of the ruler using the calendars provided. When twins or triplets are present, we recommend using the average length to determine the age of the fetuses.
To illustrate, we present data collected from the coastal plain of North Carolina and east-central Alabama. In North Carolina, females were collected in March 2009 as part of a physiological study. A total of 45 fetuses were measured and ages ranged from 86 to 151 days from date of conception. These data indicate the female with the longest fetuses, a set of twins, was bred on October 19, 2008, while the female carrying the shortest fetus was bred on December 20, 2008. The average age was 116 days from date of conception, and the average breeding date was November 20, 2008. In Alabama, females from a captive research herd were culled during June and July 2009. Twenty fetuses were measured and ages ranged from 120 to 177 days from date of conception. These data indicate that females with the longest fetuses were bred on January 18, 2009, while the females with the shortest fetuses were bred on February 15, 2009. From these data we learned two things: 1) the North Carolina females were bred over the course of two months with a peak around the third week of November, while the Alabama females were bred over a one-month period with a peak around the third week of January; and 2) the North Carolina and Alabama breeding seasons do not match. So, why are there differences?
In this case, we know that the captive herd in Alabama was comprised of males and females with a one-to-one sex ratio (or nearly so). This resulted in a more intense and short breeding season. However, the North Carolina deer were from a free-range, mostly unmanaged site where the buck to doe ratio was not balanced. This resulted in a prolonged breeding season. Although both properties had a period where much of the breeding occurred, the total range of breeding times was large. This range can be quite different between properties, states, or regions. Regarding the unmatched breeding seasons, science is still trying to understand the difference. We acknowledge that just 20 miles from where the Alabama deer were collected, across the river in Georgia, breeding is known to occur mostly in November (more like the North Carolina deer!).
The take-home message is that hunters should understand that not all females can be bred on the same day or even in the same week. In many places it is likely that breeding occurs over a number of weeks or months. But fear not! This does not mean that you cannot ambush a buck during “the peak of the rut.” To figure out when that occurs on your property, maintain behavioral data from field observation and combine it with fetus data if you can obtain it. If your state’s season does not extend late enough to examine fetuses, consult your local biologist. It is likely that he/she can provide you with local breeding dates based upon historical records and vehicle kill data.
About the Authors: Gabriel Karns is a Ph. D. candidate in Forestry and Wildlife Sciences, Auburn University; M.S., Fisheries and Wildlife Sciences Program, North Carolina State University. M. Colter Chitwood, M. S. candidate in the Fisheries and Wildlife Sciences Program, Department of Forestry and Environmental Resources, North Carolina State University.