The first question
usually asked about a big deer is ‘what does he score?’ However, we should be
asking, ‘how old is he?’ Why is the age of a deer so important? It’s not, if
your goal is to harvest a deer…any deer. But, if you’re like thousands of
other hunters out there looking to shoot “the mack-daddy”, “a bruiser”, “old
mossy horns”...and manage your property for a healthy deer herd, age certainly
becomes a factor.
The primary
obstacle to overcome when considering the age of a male deer is what the
antlers score! That’s right, antler score does not determine deer age. Despite
that, it does let us make some broad assumptions about a deer’s maturity. As a
buck reaches full adulthood their skeletal growth becomes complete, leaving
room for noncompetitive antler growth. You see, while a buck’s bone structure
is still developing, the skeleton takes precedence over antlers. Once a buck
reaches maturity, they then shift a larger percentage of their nutrient
resource to antler growth.
The challenge
becomes determining what characteristics a truly mature deer in your hunting
area displays. Just because a 140” Pope & Young deer walks by doesn’t mean
he’s a shooter…or does it? Once again, the characteristics of the deer should
help determine to shoot, not the antler score alone. If you let our example
140” buck “walk”, what will he be next year? Will he jump in to the 160” or
170” giant you’ve always dreamed of? Or, is the current 140” rack all he’s
going to be?
Determining
the important age characteristics of deer in your area can pay big. To learn
more about the age structure and genetic traits of deer in my hunting area, I
contacted Henry Chidgey, co-founder of DeerAge.com. He informed me the most
accurate way to age a deer was to tag it at birth and track it till death. Not
a realistic approach for guys trying to manage for quality deer.
Another
method Henry explained is known as eruption aging. Simply put, it’s taking a
look at when deer lose their “baby teeth” and they are replaced by permanent
teeth. The short version of a long scientific dialog is, this method only works
for deer up to 2 1/2 years of age. Beyond 2 1/2 years this method’s accuracy
rate falls off greatly.
Two other
methods exist to help us establish age structure. The first, eruption-wear, a
technique which looks at the molar tooth wear of ungulates, is commonly
practiced across the US. Unfortunately, this technique has been found to have
tremendous inaccuracy when used for aging whitetail deer. Hamlin et. al., in a
study titled “Evaluating the Accuracy of Ages Obtained by Two Methods for
Montana Ungulates”, found that tooth wear aging was only 42.9% accurate for
whitetail deer, leaving us with a 57% chance of having no idea as to the age
class of our deer.
The second
method looked at by Hamlin and his colleagues, is known as cementum annuli. This
method looks at a cross section of a select tooth at 150x magnification and
determines age from the “growth rings” present. On whitetails this was found
to be 85.1% accurate, nearly double the rate of the more commonly used tooth
wear technique.
Armed with
this information my hunting partners and I set out to see just how well we
could manage our whitetail hunting property. For starters we began collecting
lots of trail-cam photos. From which we developed a potential list of “mature
shooters”.
MJ (a large 5
x 5) cautiously entered the hay yard on a -20 degree November day. As he
quartered away at 27 yards David sailed a broadhead through both lungs. Our
first deer, a 161” Pope & Young buck was down. We all guessed his age at 5
½ years. As the season ended we identified three mature deer we hoped would
make it to next year. The first was a short racked 5 x 5 with a massive body
structure (later named Cameron’s buck). The second was a narrow, heavy
non-typical named Warren’s buck. This deer had the largest body of any on the
property. The third was a beautiful racked 5 x 6 (aka. Waylon’s buck) we
suspected would take a big jump in antler size and score well the following
hunting season.
Warren’s buck
never made it. We found him dead in late summer, the cause unknown. We
estimated him at the time of death to have been 6 ½ years old. The Triple
Browtine buck showed up late in the summer to take his place on the list of
potential shooters.
As the
season began, the debate heated up. Cameron’s buck, a 225 pound, 128” P&Y,
was the first to fall. We argued whether he was a 3 ½ or 4 ½ years old. Next
came Waylon’s buck. This deer weighed 150 pounds and scored 138“ P&Y. We
estimated his age at 4 ½ years. Finally, at the tail end of the season, Triple
Browtine got killed one mile north of our property. I found him at the local
taxidermist, weight unknown, scoring 131“ P&Y. We guessed his age to be 3
½ years. After sending all five sets of incisor teeth to DeerAge.Com here’s
the results:
With a
20% accuracy rate on our guessing you can bet the information gained from
DeerAge.Com has become invaluable. As was suggested, Pope & Young score was
a poor predictor of age for our deer. As a matter of fact our youngest deer scored
in same ballpark as deer nearly twice his age. How often does this occur in your
region of the US?
Armed
with this information we developed a checklist to determine characteristics of
mature deer (notice I didn’t say you could determine age). For deer that are
4 ½ years of age or greater I look for swayed backs, pot-bellies, a full neck,
deep chest and well rounded rump. Older bucks (5 1/2+ years) will have more
pronounced back sag, deep bellies, and their neck and brisket during the rut
appear as one giant muscle.
While
the science of aging deer on the hoof hasn’t been mastered, the art of predicting
maturity can be. Using trail cameras and having your deer kills aged by a
reputable laboratory like DeerAge.Com will help you learn the characteristics of
different age classes in your hunting area. A bonus from this in-depth look
will be an increase in the quality and quantity of big bucks on your property.