Texas Hunting Forum

Age this buck via jawbone

Posted By: kdkane1971

Age this buck via jawbone - 01/09/20 02:53 PM

Below are some pics of a buck I killed in 2017 along with several shots of his teeth. Anyone care to venture a guess on his age via the teeth? I have already gotten the results of the cementum annuli testing, however the other thread spurred me to throw these out there to see what you guys determine. I'll give it a couple days before posting the actual age.

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Posted By: kdkane1971

Re: Age this buck via jawbone - 01/09/20 02:57 PM

[Linked Image]
[Linked Image]
Posted By: Txduckman

Re: Age this buck via jawbone - 01/10/20 09:05 AM

It will probably surprise us! Obviously looks young on the ground but head gear and snout says otherwise!
Posted By: kyle1974

Re: Age this buck via jawbone - 01/10/20 03:33 PM

cementum aging isn't 100% accurate either.
Posted By: gillom

Re: Age this buck via jawbone - 01/10/20 03:55 PM

I am prepared to be surprised. I shot a deer very similar to that a few years ago. Teeth said 4.5 (by multiple people) but I knew the deer to be 7.5.
Posted By: rolyat.nosaj

Re: Age this buck via jawbone - 01/10/20 04:00 PM

I was stuck between 3.5 and 4.5. Wish I had picked 4.5
Posted By: redchevy

Re: Age this buck via jawbone - 01/10/20 05:06 PM

You cut off the most important teeth.
Posted By: kdkane1971

Re: Age this buck via jawbone - 01/10/20 08:27 PM

Originally Posted by kyle1974
cementum aging isn't 100% accurate either.


Agreed however the tooth wear method is a just a notch above junk science, there's too many variables. For deer 4.5+ the CA testing accuracy is hard to beat. We've got biologists on our place making age decisions on teeth without once seeing the deer, certainly not on the hoof and able to witness behavioral cues which also lend to age determination.
Posted By: redchevy

Re: Age this buck via jawbone - 01/10/20 08:30 PM

While CA testing may not be perfect, I think other than tagging and numbering at birth it is far and beyond the most accurate way.
Posted By: gtrich94

Re: Age this buck via jawbone - 01/10/20 08:43 PM

I'm stuck between 4.5 and 5.5 and chose 5.5. The inside of the back teeth are a little too pointy, but tooth 4 matches the description of 5.5 on the tpdw handbook.
https://tpwd.texas.gov/publications/pwdpubs/media/pwd_bk_w7000_0755.pdf
Posted By: dkershen

Re: Age this buck via jawbone - 01/10/20 10:11 PM

6.5. What do I win?
Posted By: Simple Searcher

Re: Age this buck via jawbone - 01/10/20 10:47 PM

Fun post.
I went 6.5 without looking at the actual deer picture.
I’ll stick with my first choice
I like them high brow tones
Posted By: stxranchman

Re: Age this buck via jawbone - 01/12/20 04:18 AM

Jawbone is not complete. I would call one side 5.5 and the other 6.5. From the kill photo I would call him 5.5. Not seeing him alive on the hoof and seeing his hocks I can only call him 5.5 for a nonprotein feed buck. If he was on protein then add 1 yr at a minimum.
Posted By: kdkane1971

Re: Age this buck via jawbone - 01/13/20 01:41 PM

Originally Posted by dkershen
6.5. What do I win?


Buck was aged 6.5 by CA testing. You win a fabulous prize pack of yet to be determined contents...stay tuned!
Posted By: kdkane1971

Re: Age this buck via jawbone - 01/13/20 01:52 PM

Thanks for all the participation gents. Not one of the guys on our lease got the age correct by the tooth wear method of aging. The tooth wear method is how we are instructed to age and log them for our MLD program. I believe that to be a flawed theory since it neglects to include all factors. Hopefully we can incorporate some common sense, and CA testing, towards determining the actual age of the deer we kill as opposed to the subjective alternative.
Posted By: kdkane1971

Re: Age this buck via jawbone - 01/13/20 01:54 PM

Originally Posted by stxranchman
Jawbone is not complete. I would call one side 5.5 and the other 6.5. From the kill photo I would call him 5.5. Not seeing him alive on the hoof and seeing his hocks I can only call him 5.5 for a nonprotein feed buck. If he was on protein then add 1 yr at a minimum.


We do have a handful of free choice protein available for several months out of the year. 4 protein feeders for the 2000 acres we hunt.
Posted By: tlk

Re: Age this buck via jawbone - 01/13/20 03:52 PM

according to this none of the methods is very accurate


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Posted By: redchevy

Re: Age this buck via jawbone - 01/13/20 03:57 PM

Interesting results. It does indicate that over all CA is about 60%. Wonder how far off it is when it was off? Also wonder if there was any error in determining the age when the deer were captured and tagged.
Posted By: stxranchman

Re: Age this buck via jawbone - 01/13/20 04:05 PM

Originally Posted by kdkane1971
Originally Posted by stxranchman
Jawbone is not complete. I would call one side 5.5 and the other 6.5. From the kill photo I would call him 5.5. Not seeing him alive on the hoof and seeing his hocks I can only call him 5.5 for a nonprotein feed buck. If he was on protein then add 1 yr at a minimum.


We do have a handful of free choice protein available for several months out of the year. 4 protein feeders for the 2000 acres we hunt.

How many years have y'all seen this buck?
Posted By: tlk

Re: Age this buck via jawbone - 01/13/20 05:50 PM

Originally Posted by redchevy
Interesting results. It does indicate that over all CA is about 60%. Wonder how far off it is when it was off? Also wonder if there was any error in determining the age when the deer were captured and tagged.


Says known age of all bucks in study so I would assume they took the deer from birth. Also at the ages that count for a lot of leases (5 and 6) it is under 50% accurate. Not very good percentages in my opinion
Posted By: kdkane1971

Re: Age this buck via jawbone - 01/13/20 10:28 PM

Originally Posted by redchevy
Interesting results. It does indicate that over all CA is about 60%. Wonder how far off it is when it was off? Also wonder if there was any error in determining the age when the deer were captured and tagged.


I imagine the numbers in the table would show a greater disparity between the TRW and CA if it took real-world application in account. Certainly the folks conducting the study were well-versed in the TRW methodology. Most of the utilization of the TRW however is performed by everyday folks with no formal training or expertise. There can also be a bias involved when the analysis is solely objective. The largest gap in disparity shown in the table shows to be when those bucks are 4.5 - 6.5, what I imagine most properties outside of south Texas consider mature and killable. The minimum age for a trophy on our place is 5.5. In fact, looks like the likelihood of the CA being more accurate than TRW at age 5.5 is about 48% vs 25%, factor in everyday Joe's doing the TRW and that 25% falls even more. Of course, some people have more expertise than others, but overall I believe the it's less likely that the general hunter has a great grasp on TRW. I was told by the manager of large (LF) property that the jaws above were from a 3.5-4.5 yo. Jaws were in his hand too. That was my fist huge red flag that the TRW method is junk science.

Even the numbers in the table show the CA trumps the TRW every time, and especially if someone's TRW opinion contradicts what I see, and what I saw while judging the deer on the hoof. If the CA is truly science, I would also expect the margin of error to decrease based on the growing sampling size, at least until the limits of the technology are attained.
Posted By: kdkane1971

Re: Age this buck via jawbone - 01/13/20 10:45 PM

Originally Posted by stxranchman
Originally Posted by kdkane1971
Originally Posted by stxranchman
Jawbone is not complete. I would call one side 5.5 and the other 6.5. From the kill photo I would call him 5.5. Not seeing him alive on the hoof and seeing his hocks I can only call him 5.5 for a nonprotein feed buck. If he was on protein then add 1 yr at a minimum.


We do have a handful of free choice protein available for several months out of the year. 4 protein feeders for the 2000 acres we hunt.

How many years have y'all seen this buck?


No one mentioned seeing or knowing the buck, but there is no real information sharing going on. It's unfortunate, but for some reason that's the way it is. The deer in Concho County travel long distances too. We see mature bucks every year that have never been seen before. I saw him on the hoof the afternoon 24 hours prior to the day I killed him. Watched him from 330pm to dark during which he was anywhere from 50 - 250 yards from my position. He really should have been a management buck, but since we didn't have that option (only cull & trophy), I took him for the betterment of the herd as my trophy. He was an aggressive, [censored]-blocking, dude.
Posted By: redchevy

Re: Age this buck via jawbone - 01/13/20 11:01 PM

Originally Posted by tlk
Originally Posted by redchevy
Interesting results. It does indicate that over all CA is about 60%. Wonder how far off it is when it was off? Also wonder if there was any error in determining the age when the deer were captured and tagged.


Says known age of all bucks in study so I would assume they took the deer from birth. Also at the ages that count for a lot of leases (5 and 6) it is under 50% accurate. Not very good percentages in my opinion

It says known age because they were captured as fawns or yearlings, so as I read it someone was still determining if they were fawns or yearlings, which may include some error.
Posted By: tlk

Re: Age this buck via jawbone - 01/13/20 11:02 PM

Originally Posted by kdkane1971
Originally Posted by redchevy
Interesting results. It does indicate that over all CA is about 60%. Wonder how far off it is when it was off? Also wonder if there was any error in determining the age when the deer were captured and tagged.


I imagine the numbers in the table would show a greater disparity between the TRW and CA if it took real-world application in account. Certainly the folks conducting the study were well-versed in the TRW methodology. Most of the utilization of the TRW however is performed by everyday folks with no formal training or expertise. There can also be a bias involved when the analysis is solely objective. The largest gap in disparity shown in the table shows to be when those bucks are 4.5 - 6.5, what I imagine most properties outside of south Texas consider mature and killable. The minimum age for a trophy on our place is 5.5. In fact, looks like the likelihood of the CA being more accurate than TRW at age 5.5 is about 48% vs 25%, factor in everyday Joe's doing the TRW and that 25% falls even more. Of course, some people have more expertise than others, but overall I believe the it's less likely that the general hunter has a great grasp on TRW. I was told by the manager of large (LF) property that the jaws above were from a 3.5-4.5 yo. Jaws were in his hand too. That was my fist huge red flag that the TRW method is junk science.

Even the numbers in the table show the CA trumps the TRW every time, and especially if someone's TRW opinion contradicts what I see, and what I saw while judging the deer on the hoof. If the CA is truly science, I would also expect the margin of error to decrease based on the growing sampling size, at least until the limits of the technology are attained.



What is concerning about this is if you are doing serious management like we are then neither of these methods seems solid on older deer (assuming one accepts the study). So the only way I know of to try to make sure of the trophies you take is to follow them via trail cameras and personal observation over the years.
Posted By: kdkane1971

Re: Age this buck via jawbone - 01/13/20 11:02 PM

[Linked Image]
Posted By: kdkane1971

Re: Age this buck via jawbone - 01/13/20 11:07 PM

Originally Posted by tlk
Originally Posted by kdkane1971
Originally Posted by redchevy
Interesting results. It does indicate that over all CA is about 60%. Wonder how far off it is when it was off? Also wonder if there was any error in determining the age when the deer were captured and tagged.


I imagine the numbers in the table would show a greater disparity between the TRW and CA if it took real-world application in account. Certainly the folks conducting the study were well-versed in the TRW methodology. Most of the utilization of the TRW however is performed by everyday folks with no formal training or expertise. There can also be a bias involved when the analysis is solely objective. The largest gap in disparity shown in the table shows to be when those bucks are 4.5 - 6.5, what I imagine most properties outside of south Texas consider mature and killable. The minimum age for a trophy on our place is 5.5. In fact, looks like the likelihood of the CA being more accurate than TRW at age 5.5 is about 48% vs 25%, factor in everyday Joe's doing the TRW and that 25% falls even more. Of course, some people have more expertise than others, but overall I believe the it's less likely that the general hunter has a great grasp on TRW. I was told by the manager of large (LF) property that the jaws above were from a 3.5-4.5 yo. Jaws were in his hand too. That was my fist huge red flag that the TRW method is junk science.

Even the numbers in the table show the CA trumps the TRW every time, and especially if someone's TRW opinion contradicts what I see, and what I saw while judging the deer on the hoof. If the CA is truly science, I would also expect the margin of error to decrease based on the growing sampling size, at least until the limits of the technology are attained.



What is concerning about this is if you are doing serious management like we are then neither of these methods seems solid on older deer (assuming one accepts the study). So the only way I know of to try to make sure of the trophies you take is to follow them via trail cameras and personal observation over the years.


I agree 100%. It takes a combination of factors to make an accurate age assessment. Our program bases the age on TRW without pause to hunter evaluation which arouses my concern about the legitimacy of our overall "program".
Posted By: tlk

Re: Age this buck via jawbone - 01/13/20 11:34 PM

Originally Posted by kdkane1971
Originally Posted by tlk
Originally Posted by kdkane1971
Originally Posted by redchevy
Interesting results. It does indicate that over all CA is about 60%. Wonder how far off it is when it was off? Also wonder if there was any error in determining the age when the deer were captured and tagged.


I imagine the numbers in the table would show a greater disparity between the TRW and CA if it took real-world application in account. Certainly the folks conducting the study were well-versed in the TRW methodology. Most of the utilization of the TRW however is performed by everyday folks with no formal training or expertise. There can also be a bias involved when the analysis is solely objective. The largest gap in disparity shown in the table shows to be when those bucks are 4.5 - 6.5, what I imagine most properties outside of south Texas consider mature and killable. The minimum age for a trophy on our place is 5.5. In fact, looks like the likelihood of the CA being more accurate than TRW at age 5.5 is about 48% vs 25%, factor in everyday Joe's doing the TRW and that 25% falls even more. Of course, some people have more expertise than others, but overall I believe the it's less likely that the general hunter has a great grasp on TRW. I was told by the manager of large (LF) property that the jaws above were from a 3.5-4.5 yo. Jaws were in his hand too. That was my fist huge red flag that the TRW method is junk science.

Even the numbers in the table show the CA trumps the TRW every time, and especially if someone's TRW opinion contradicts what I see, and what I saw while judging the deer on the hoof. If the CA is truly science, I would also expect the margin of error to decrease based on the growing sampling size, at least until the limits of the technology are attained.



What is concerning about this is if you are doing serious management like we are then neither of these methods seems solid on older deer (assuming one accepts the study). So the only way I know of to try to make sure of the trophies you take is to follow them via trail cameras and personal observation over the years.


I agree 100%. It takes a combination of factors to make an accurate age assessment. Our program bases the age on TRW without pause to hunter evaluation which arouses my concern about the legitimacy of our overall "program".


yes - decisions on if a hunter shot a trophy that was not "mature" is based off tooth wear and CA apparently can be "iffy" - would love to see if there are any other studies on the CA.

I did see a study a few years ago similar to this one but just limited to biologist using tooth wear - top end biologist were used and the results were not good on their ability to age by tooth wear
Posted By: redchevy

Re: Age this buck via jawbone - 01/14/20 01:41 PM

I don't put all my eggs in one basket either. I like to stack as much as I can to get the best guess I can. The last buck we sent teeth in on for CA came back at 6. We had pictures of him for 4 years and thought he was 5, but it was always a debate between 5-6. Looking at his teeth for wear most would probably say he was 3, I probably would have too if I didn't know better.
Posted By: kdkane1971

Re: Age this buck via jawbone - 01/14/20 02:42 PM

I found this info from a study on the Evaluation of the Applicability of Different Age Determination Methods for Estimating Age of the Endangered African Wild Dog (Lycaon Pictus) https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5061369/

"A number of methods exist to assign age and age class to individuals based on the examination of teeth. However there is a great need for a reliable age estimation method for wild dogs that employs a simple and easily applied technique. It is also important to remember that any error in age estimation may seriously bias estimates of age-dependent life-history parameters and this may affect our understanding of population dynamics and may result in flawed management strategies [29]. This study has shown that linear equations obtained from the relationship between chronological age and (i) age estimated by counting cementum annuli, (ii) pulp cavity/tooth width ratio and (iii) tooth wear (measured by tooth crown height) can be applied to estimate the chronological age of unknown age wild dogs. Age estimated by counting cementum annuli was the most reliable method for estimating chronological age of wild dogs with a 79% predictive capacity.

Numerous age determination studies across a wide range of species have reported counting cementum annuli as the most accurate age determination method. Earlier studies by Smuts, Anderson [16] found a significant relationship between cementum lines and known age in lions (P. leo) with a very high predictive capacity of 97%. Boertje, Ellis [25] studied the accuracy of moose (Alces alces) age determination from cementum annuli and found a significant relationship between known age and number of cementum annuli, with 74% of 76 canines being assigned a correct age. A strong relationship was also found between number of cementum annuli lines and age of polar bears (Ursus maritimus), with the most experienced cementum annuli reader scoring 75% of the specimens to their correct known age [30]."
Posted By: kdkane1971

Re: Age this buck via jawbone - 01/14/20 03:00 PM

BTW that Texas A&M - Kingsville study was from 2010 - I sure hope the margin of error has decreased over the last 10 years.

Some other interesting tidbits from the 2010 study;
https://www.ckwri.tamuk.edu/sites/d...nsidedeerresearchnewsletter-fall2010.pdf
* collected 264 mandibles from 134 deer at least 2 yrs old
* Six biologists, holding at least a Master’s degree in Wildlife Science, aged these jaws while referring to the original scientific paper (Severinghaus 1949) on aging deer using tooth wear and a visual guide to the technique.
* These trained biologists, with references in hand, categorized only 49% of jawbones correctly (Figure 1).
* Biologists tended to under-age deer that were greater than 3 years old, but ages were correct ±1 year for 86% of the jaws.
* All 6 observers agreed on the same age for a jaw only 19% of the time, and average agreement for a particular jawbone was 4.1 observers/jawbone.
* sent 232 known-age incisors to a lab for such an analysis. Cementum-annuli aging resulted in 61% accuracy and was correct ±1 year for 92% of the jaws
* Estimating the age of a deer by tooth wear is inaccurate because of variation in tooth wear patterns among deer. Variability is also added by multiple subjective criteria that can be interpreted differently by different people.
Posted By: dkershen

Re: Age this buck via jawbone - 01/14/20 07:51 PM

Originally Posted by kdkane1971
Originally Posted by dkershen
6.5. What do I win?


Buck was aged 6.5 by CA testing. You win a fabulous prize pack of yet to be determined contents...stay tuned!

Waiting with baited breath. wink

I've aged a lot of mule deer in my day. White tails aren't a lot different.
Posted By: stxranchman

Re: Age this buck via jawbone - 01/15/20 02:47 AM

Originally Posted by dkershen
Originally Posted by kdkane1971
Originally Posted by dkershen
6.5. What do I win?


Buck was aged 6.5 by CA testing. You win a fabulous prize pack of yet to be determined contents...stay tuned!

Waiting with baited breath. wink

I've aged a lot of mule deer in my day. White tails aren't a lot different.

I was on a ranch last year in the lower Panhandle in early Jan. that was MLD and they killed some mule deer. Two of us aged the jaws and then the biologist aged them. All were sent off for CA testing. Two of us aged one MD buck at 5 or 6 on the hoof and by toothwear and the biologist said 3.5 and he came back as a 7.5 yr old via CA. Two of us aged another MD buck at 7+ and the biologist said 4.5 and he came back 10.5 via CA. Another MD buck was aged on the hoof and shot as a 3 yr old 2x2 but his tooth wear looked more 2.5....he came back at 4.5 yrs old via CA. Every MD that was killed on that ranch was older than what the jawbones showed compared to what a WT would age by comparison. I killed a WT that looked 5 or 6 on the hoof and one side of his jaw showed 5 and the other little more 6..CA on him was 6.5. None of the deer looked their age (CA age) except the MD that we aged at 7+. One guys said he has learned that MD generally run 1 yr older if you use the WT age for that toothwear on the MD. I have aged a ton of WT but not many MD. The only ones I have aged have been the ones I have killed. I killed a MD in the Trans Pecos this season that I had seen in 2016 the final morning of the season when I was hunting with a friend. He passed him since he was not what he was looking for and both of us thought he was a 4 or 5 yr old then. I killed him this year in 2019 and his toothwear only shows 5.5 to me. I know it is the same buck due to the unique right antler side tine growth he had in 2016 and 2019 and then where he was killed on the ranch compared to where I seen him in 2015 and 2016(within a section of land). I am sending the teeth off for CA on him to get an age from them. I know the deer has to be older than 5 but toothwear does not show it. The buck looked 7 on the hoof this year. Aging by toothwear or CA is not going to ever be 100%. What I look for is consistency from the person aging them. History on the deer is more accurate IMO than tooth aging.
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