Every year there are a handful of bucks that shed their antlers early. . .like December early. What’s with this early antler drop? Let’s take a look at what causes early antler shedding on both an individual and local herd level.
First, let’s figure out what causes a buck to shed his antlers in the first place. It’s a relatively simple process to understand – photoperiod (amount of daylight) signals changes in testosterone levels, which control antler growing (velvet), hardening, and casting (shedding) periods. In short, once testosterone levels dip below a certain threshold, it triggers other physiological processes to begin and antlers fall off shortly after. Check out the graph below for a simplified understanding as to how the testosterone level influences the yearly antler cycle.
Now, what causes some bucks to drop early? For ease of reference, let’s assume any antlers shed during December are considered “early” sheds, as it’s roughly a month before most areas experience peak shedding. As I mentioned before, let’s first break it down by individual cases and then by site or regional wide cases where many bucks are seemingly dropping antlers earlier than normal.
A buck that shed its antlers well before most other bucks in the area is what we mean by shedding on the individual level. When it’s not the norm of the population or even that buck, we can assume there’s something happening to that specific individual that’s causing an earlier than normal suppression of testosterone, thus shedding early. Many bucks have been known to drop their antlers within the same week year after year, and with the prevalence of trail cameras these days, it’s not all that difficult to determine when a specific buck lost his antlers. If all of a sudden, he dropped them a month earlier than the previous year, there’s a pretty good chance he’s experiencing more stress for one reason or another.
While photoperiod is the overriding trigger of the shedding process in a healthy herd, stress and genetics also play a role. Stressful circumstances resulting from injuries, fighting, poor nutrition, and severe winters can often lead to an early reduction of testosterone levels, thus an earlier antler drop. In individual cases as we talked about above, injuries to the deer are usually the cause for early antler drop.
Now, moving on to antler shedding on a larger scale, as it seems like this year in Wisconsin and some other parts of the country – in this instance, weather, nutrition, and herd dynamics are the likely culprits.
Of the three factors just mentioned, weather is likely to be the largest variant from year to year especially in the northern half of the country where snow flies. Snow and freezing temperatures are the two weather influencers thought to impact early antler dropping the most. Of the two, snow cover is likely more influential because of how it renders a lot of ground browse unavailable and creates high-energy-expending travel conditions. If both, snow cover and extreme cold temps are present, you can bet the local deer herd is under stress. Of course, the amount of stress is relative to what the “normal” conditions are in a certain area. Obviously, deer in Upper Michigan are used to harsher conditions earlier in the season compared to Kansas deer, for instance. Perhaps this is one reason you don’t see Canada bucks shedding much earlier than the rest of the bucks in North America.
As you know, stressful weather conditions and nutritional stress often go hand-in-hand. For example, an early December snowstorm covers up much of the preferred browse, thus creating earlier than normal nutritional stress. This could result in an earlier than normal antler drop for the local bucks affected by the snow.
Another cause for nutritional stress may be dramatic change in land use or farm practices. Crops may have been tilled under, a subdivision was developed in a preferred wintering area for deer, or flooding occurred, or drought conditions were present, etc… All can put extreme nutritional stress on a herd, perhaps causing an early antler drop for many bucks.
Out-of-Whack Herd Dynamics
Remember, the antler shedding process circles back to testosterone levels, and herd dynamics can be a strong regulator of a buck’s testosterone level. Herd balance comes down to two main factors: Buck to Doe ratio, and proportioned age classes of bucks.
The more balanced a herd is, the more intense rut you can expect. An intense rut, meaning intense competition for does, can lead to nutritionally stressed and run down bucks…thus, the potential for early sheds. In unbalanced herds with more does, the opposite could be expected. The reason being continually cycling does will keep bucks’ testosterone levels higher than normal for a longer period of time, and if you look back at the chart, you can see how that would potentially delay the normal timeframe a buck would cast its antlers.
It’s interesting to see a ‘higher than normal’ amount of early shedding this year, but I’ll still focus my shed hunting efforts towards the months of February and March for the most part, when I know the majority of bucks have dropped. This is, of course, unless my trail cameras or Facebook tells me differently.
Good luck shed hunting this season and as always, MILES=PILES!