jawbone/ buck age and observation about jawbones

[pass-thru]

Here are a couple pics of a buck I shot yesterday...the jawbone and trailcam pics. He was on the target list because from the body he appears to be at least 3 years old, and that is my threshold. The jawbone has very little wear. For over twenty years I have boiled out every jawbone from the deer that I have killed that was at least two years old...with maybe a couple of late season long yearling does as well.

One thing that I have noticed is that on most classic 2 year olds the last cusp of the back molar has a high gum line. On this buck it does not have a high gum line, which to me indicates that he older than 2. Is this legit clue for purposes of jawbone aging? I will post a pic of the jaw from a done I shot last month next to the buck jawbone as an example. Also, some older deer do have a higher gumline, but not as high as the example, and are easy to distinguish.

 

[megalomaniac]

The jawbone in the first pic is pretty classic for 3.5 IMO. Corresponds nicely with the trail cam pics.

I'm not sure what you are referring to a high gumline... BUT if you are referring to how far the last molar has erupted from the bone itself, then yes, that can be another subtle clue to the deers age between 1.5 and 3.5.

But an even better subtle clue to a deers true age is the 3rd premolar. So many folks just focus on wear on the molars... but if you look at the 3rd jawbone you posted (which may be the same as the first jawbone), the amount of wear on the 3rd premolar is even greater than the jawbone just above it... both are 3.5yos, even tho the jawbone from the one labeled as doe has more wear on the first molar. Hope I explained that where it makes sense.

 

[BSK]

I agree with Mega. If someone handed me that jawbone - even without the trail-cam pictures - I would say 3 1/2. And not because of the wear on the 1st molar (4th tooth). But because of the wear on the premolars (first 3 teeth). That's WAY too much wear for a 2 1/2.

 

[pass-thru]

Thanks I appreciate the feedback. I did not notice the pre-molars too much. I was surprised at the overall lack of dentin exposed on the molars.

There is a lot of variation from jawbone to jawbone. Several years ago I sent off a box to Matson's. Most came back with a high confidence age that was consistent with my estimate based body, trailcam history, etc. A couple came back with a "B" confidence and an estimated range. The one thing that stood out was that the deer from my farm generally have little wear compared to some off the other areas I sent jawbones from.
Even so I will occasionally be very stumped by a jawbone. For instance one buck everybody thought was 4+ based on trail cam pics. The jawbone had no clues to get it over 2. Matson's came back with an age of 3, B confidence with a range of 2-3. Go figure.

 

[BSK]

The one thing that stood out was that the deer from my farm generally have little wear compared to some off the other areas I sent jawbones from.

There can be a huge difference in wear from one location to another. Much depends on what the primary food sources are in the area. Deer eating ag crops won't display anywhere near the wear deer eating woody browse and acorns do.

Even so I will occasionally be very stumped by a jawbone. For instance one buck everybody thought was 4+ based on trail cam pics. The jawbone had no clues to get it over 2. Matson's came back with an age of 3, B confidence with a range of 2-3. Go figure.

I don't have to figure. I've seen the studies with known-age deer. NO aging method is all that accurate. That's why I use several and go with the average unless there is something truly compelling to throw out one of the ages. For example, toothwear almost never over-ages a deer. In fact, the older the deer actually is, the more toothwear tends to under-age the deer. So if a younger looking deer shows the toothwear of a much older deer, the deer is almost certainly much older than it appears.