Sounds like wherever it is, if the herd is more balanced that what is common in some places in Michigan, bucks may keep antlers later, as they aren't as stressed. And if not as stressed, they have bigger antlers the next year and so on.
Whitetail Science – Sheds
By: Brian Murphy
Shed Science
Like most deer hunters, I love finding shed antlers. Perhaps it’s because each antler is as unique as a human fingerprint, or because it provides hints as to where a buck lives, his age, his antler quality and even his dominance rank in the herd. Regardless, I view each shed antler as a prize worthy of keeping, much like an arrowhead, and something tangible from a deer and a deer herd from which much can be learned.
As a young hunter I rarely found shed antlers, supposedly because they all were eaten by squirrels and rats – at least that’s what the local ‘experts’ told me at the time. While it’s true that rodents and numerous other animals, including deer, will chew on cast antlers, the main reason hunters don’t find shed antlers is because few bucks survive the hunting season in many areas. To make matters worse, most bucks that do survive in these overhunted areas are yearlings and their antlers are small, which makes them even more difficult to find.
The good news is that an increasing number of hunters are practicing Quality Deer Management, resulting in more bucks surviving each hunting season. This greatly increases your chances of finding a shed antler – especially one larger than a key chain ornament. In fact, in recent years shed hunting has become so popular that it has even spawned its own association and record book. Some hunters now pay for access to properties on which to search for shed antlers and a few even train dogs to find cast antlers.
However, beyond the size of a shed antler, few hunters realize how much additional information it can provide - not just about the individual deer that dropped it, but also about the overall health of the deer herd and its habitat. The most obvious information provided by a shed antler is the approximate age and antler size of the buck that dropped it. In most cases, I double the score from one antler and add a conservative inside spread measurement to get an idea of the buck’s approximate gross Boone and Crockett (B&C) score. Then, using age and average gross B&C data from other bucks harvested on the same property, I place the buck into one of four age categories – yearling, 2 _, 3 _ and 4 _ years old or older. In the absence of an entire shed antler from which to calculate a gross B&C score, you can use main beam circumference one inch above the burr and/or main beam length to estimate a buck’s age, as long as you have enough data from previous years to enable an accurate age prediction.
With enough shed antlers, you can not only get an idea of the bucks that survived the previous hunting season, but you also can estimate the upcoming season’s buck age structure and antler potential. If the shed has any unique features such as forked tines, drop tines or abnormally long or short points, they also can be useful for identifying the same buck in future years. Nothing adds more enjoyment and satisfaction to the harvest of a mature buck than to have shed antlers from the same buck during one or more previous years.
The timing of antler casting also is important. Research has revealed that both nutrition and dominance rank can influence when a particular buck will cast its antlers. For example, Michigan researcher John Ozoga noted that providing supplemental feed to bucks delayed their average antler casting date by more than a month from late December to mid February, with some bucks even carrying antlers into March. Likewise, bucks under extreme nutritional stress will cast their antlers early, some even before the end of hunting season. This situation is particularly common in eastern hardwood forests that rely on annual acorn crops. In years of widespread acorn failures, bucks often shed their antlers several weeks earlier than normal. Nutritional stress also can result from extreme or prolonged rutting activity, especially if the buck did not enter the rut in prime physical condition or if he had inadequate nutrition immediately following the rut.
Researchers also have documented that the interaction between a buck’s dominance rank and the length of the breeding season can affect timing of antler casting. In general, a buck’s dominance rank is affected by age, body weight and testosterone levels – all of which typically increase with age, at least until 5 _ years.
However, the affects of these factors appear to vary according to latitude (North vs. South). In northern latitudes, where the rut is generally shorter and more intense, dominant bucks generally cast their antlers earlier than lower ranking bucks. This is presumed to be the function of elevated testosterone levels during the shorter breeding period, followed by a rapid decline in these hormone levels and antler casting. The survival advantages of this are clear – bucks in these harsher environments can terminate breeding earlier and rebuild necessary body reserves to survive the winter.
In contrast, Kenneth Forand and others at The University of Georgia documented that dominant bucks generally shed their antlers later than lower ranking bucks. They speculated that this was due to the longer and less intense breeding season during which bucks face lower stress levels compared to northern deer. This allows bucks in southern latitudes to remain in better physical condition, maintain elevated testosterone levels, and a competitive breeding advantage over lower ranking bucks.
Physical and/or nutritional stress caused by diseases, parasites and injuries also can result in premature antler casting. In southern ranges where epizootic hemorrhagic disease (EHD) and blue-tongue virus outbreaks are fairly common, bucks that survive infection often cast earlier during the year of infection. Heavy infestations of internal or external parasites also can cause earlier antler casting. In most cases, heavy parasite concentrations are indicative of overpopulated, stressed deer herds in need of immediate management attention.
When latitude, nutrition, health and buck age structure remain relatively constant from year to year, such as is common in many managed deer herds, individual bucks generally cast within a few days of the same date each year. For example, a study by Dr. Harry Jacobson at Mississippi State University involving 24 captive bucks revealed an average of only 4.4 days variation in annual casting dates among individual bucks, with the longest being 17 days for one buck.
Given the above, it is clear that much insight can be gained from shed antlers. Not only does the antler reveal a buck’s relative age and antler quality, it also provides insight as to the status of the overall deer herd as it relates to habitat quality. If you regularly find cast antlers before the end of the hunting season in your area, there’s a good chance that nutrition is limiting. On the other hand, if bucks regularly hold their antlers well beyond the normal casting time, nutrition likely is adequate. However, it should be kept in mind that early casting by mature bucks is more common in the North than in the South.
So, the next time you find a shed antler, take the time to consider all the information it can provide. With enough shed antlers from a given property over time, you can monitor the status of your deer herd and make informed management decisions in the future. By the way, shed antlers also make nice additions to your bookshelf and mantle.
SHED HUNTING SECRETS
Recently, the Quality Deer Management Association (QDMA) interviewed many of its members who are avid shed antler hunters and collectors. The information, part of an article in the February 2006 issue of QDMA’s Quality Whitetails, included these useful tips for locating sheds:
• Use infrared-triggered trail cameras to monitor antler shedding. Begin hunting sheds as soon as most or all bucks in the photos have dropped their antlers (timing will vary geographically). Rodents will immediately begin gnawing shed antlers, so don’t postpone your search until warmer weather.
• Concentrate your search in these areas: 1) winter food sources, especially cool-season food plots (searchers rate these as the top location for producing sheds); 2) bedding areas or winter cover; 3) along trails and in bottlenecks linking the first two areas; and 4) near water sources if water sources are limited on your hunting land.
• Focus especially on areas along travel routes where deer must jump, like fence, ditch or creek crossings, as antlers are often jarred loose at these locations. Places where brush is especially dense along trails are also productive, and sheds may even be found hanging above ground level.
• Most shed hunters believe it is okay to enter bedding areas and sanctuaries to hunt for sheds in the off-season, but they recommend limiting your intrusion to one thorough search each year.
• Ovals in snow or in bedding cover where deer bed down are productive because of the increased chance of finding a matched set or spotting very small shed antlers.
• Walk slowly and take the time to scan downrange but also very close to your feet. While some sheds will be obvious, most are spotted within one or two strides of your path. If you are distracted by rubs or other deer sign, slow down and remember to keep your eyes on the ground.
Brian Murphy is a Certified Wildlife Biologist and Executive Director of the Quality Deer Management Association. This column originally appeared in Bowhunting World magazine. Visit www.QDMA.com and http://ift.tt/1UEka0u for more information.
Antlers still on in March
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