How old was that Deer that you harvested?

Every year I hear someone say that they wish they knew how old a certain deer was that they had shot previously. Even though they may be asking strictly out of curiosity the fact of the matter is, that is an important question. In any deer management program knowing the age of the deer is critical in determining how the management plan is working. Even if you don’t give a care about managing your deer population you should be interested in the age structure of your deer population and you should be interested in anything that may allow you to improve your hunting. Most people don’t want to bother with removing the jawbone because they think it will be a real complicated procedure. It’s not. If you have not done so already please watch my video “How to remove a Deer Jawbone”. I show you the two methods that we use to remove the jawbone. If you can at least pull the jawbones and then indicate on them what deer they are from you can get the jawbones aged at a later date if you aren’t able to do it yourself. One suggestion I would like to make is that if it is a Buck that you are removing the jawbone from it would be nice if you took a picture of the Buck before you field dress him so the person ageing the jawbone can look at the picture if there is any doubts about the age indicated by the jawbone. Try to get a picture that shows the Buck’s entire body including his swollen neck. If you actually have a trail cam picture of the Buck from just before or during the rut this will more than suffice. I believe most state deer biologists would be happy to age the jawbones for you. Don’t expect them to come driving right over but I’m sure if you contact them they will work out a mutually convenient time and place to look at the jawbones with you. If you’re going to do this, then you might as well pull the jawbone from every deer that you and your fellow hunters harvest so the person can age a few jawbones for you instead of just one. Not only will this educate you about your deer population it will give the biologist some valuable insight into your deer population as well. If you can keep this harvest information for multiple seasons you can now develop a history that can be invaluable in analyzing your deer population. If you can present this kind of information to a deer biologist you will see them smile from ear to ear. This is the kind of information that they need to analyze a deer population. We now have our harvest information all the way back to 1996. When we combine this with our sightings information since 1996 we can tell you whatever you need to know about our deer population. With the harvest information and sightings information that we keep we are able to monitor and manage our deer population quite successfully. We have been doing this by using our software that we have now made available on the internet. Whether your property is under a high fence or not it is important for you to monitor your deer population.

Let’s talk about the accuracy in ageing a jawbone using tooth wear. This is one of the subjects where you can ask 10 different biologists and probably get a few different opinions. I feel that you can be 98% accurate ageing a fawn, 1 ½ year old and 2 ½ year old deer. At 3 ½ years old the accuracy goes down a little bit and at 4 ½ years old and older it goes down even more. There are times when I look at a jawbone and it is border line at two different ages. The jawbone may look 3 ½ or 4 ½ so I will definitely pull both sides of the jawbone to see if they both look the same. We try to maximize our accuracy with our Bucks by analyzing the body characteristics in conjunction with the jawbone. If the age indicated by the jawbone is border line between two ages then we use the body characteristics to make the final determination. With regards to Does if we are off a year it really doesn’t matter. As long as we can break out fawns, 1 ½ and 2 ½ year old Does it’s no big deal if the Doe is 3 ½ or 4 ½ years old or if she is 6 ½ or 7 1/2 years old.

Let me get back to the guy that was curious about how old that Buck was that he shot a while back. Even though he considered the Buck a big antlered Buck if he now learns that the Buck was only 2 ½ years old he just might ask himself what this Buck would have looked like with another year of antler growth. This is exactly what happened to us several years ago. We were shooting these Bucks that had over 140” of antler (which is big for our area) but then determined that most of them were 3 ½ years old. We couldn’t help but wonder what these Buck’s antlers would have looked like with another year of growth. This definitely affected our deer management with regards to our selective harvest criteria. It became important that we learn how to age these Bucks on the hoof. If you have not done so already please make sure you watch my video “How to age a Buck on the hoof”. As a result of this finding we started letting these 3 ½ year old Bucks with good antlers walk and shooting the 3 ½ year old Bucks with poor antlers. Remember that everyone’s situation is different so you will obviously have to make the decision that best fits your own specific situation. Knowing the age of the deer that you harvest can definitely affect your deer hunting strategy. If you suddenly realize that most of the Bucks that are being harvested on your property are 1 ½ years old then you may make the decision amongst your group that it would be nice to at least let these Bucks make it to 2 ½ years old. You can accomplish this by learning how to age a Buck on the hoof or possibly by implementing an antler restriction. (Just make sure it’s the right antler restriction. See my article Analyzing your Bucks Antler Characteristics)

Another reason for knowing the age of the deer that you harvest is that if you are trying to analyze the weight of your deer or the antler size of your Bucks then knowing the age is critical. A 1 ½ year old deer won’t weigh as much as he will at 2 ½ years old. He will then weigh more at 3 ½ years old. In the same token he will have bigger antlers at 2 ½ than he had at 1 ½ years old. You get the idea. So when I am studying body weight and antler size I have to analyze it by the age of the deer.

In summary if you are field dressing your deer then why not add one more step to the process and pull the jawbone. If you aren’t field dressing your own deer then at least pull the jawbone. Just remember that if you are going to mount the deer then do not cut the hide. The easiest thing to do if you are mounting a deer is to ask the taxidermist to save the lower jawbone for you. If you can’t wait for the taxidermist to remove it then use the second method on my video to pull the jawbone. You may be surprised at the ages of the deer that you are harvesting. With this additional knowledge you may be able to make some decisions that will improve your hunting in the future. Remember that you cannot age a Buck by his antlers or his body weight. The jawbone will be the most accurate tell of the Buck’s and Doe’s age and the Buck’s body characteristics will be the next indicator of his age. We don’t have to be accurate 100% of the time. We just need to be accurate most of the time and when we’re dealing with deer over 4 ½ years old it really doesn’t affect our analysis if we’re off a year or two. So start trying to improve your deer population next season and pull the jawbones of all of the deer that you harvest so you can start getting a feel for the age structure of your own deer population. I assure you that no one else can do this for you if you don’t provide them with the information that is needed to do this analysis. If you will start keeping the information and utilize our software you can get the information you need to analyze your own deer population and will have the information if you decide to work with a biologist. You need to do your own record keeping and not assume anything.

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