Have you ever harvested a whitetail and wondered to yourself just how old that animal is? There are many reasons why it is useful to be able to age a whitetail. For the purpose of keeping information about population health as well as to make body condition comparisons that are accurate across the board, knowing a deer's age is quite helpful. The question is how do you actually make an age determination? There are actually two ways to do this, those being by physical examination or that of teeth, the latter of which we will discuss today.
Aging whitetails by their teeth is a practice that has been around for decades. It involves the examination of tooth number as well as growth and wear characteristics in order to determine an approximate age. The number of teeth as well as the color and physical structure all play a part in age estimations. By learning how to recognize wear patterns as well as the types of teeth and the normal coloration for certain ages, you, too, can figure out about how old each deer is that you harvest.
In order to age a deer, you will first need to be able to see the teeth. Depending on your plans for mounting, you may not want to cut flesh in or near the teeth, but prying the mouth open with a jaw spreader will give you a good place to start. Once you are able to see teeth, the first thing you want to do is count them. At birth, fawns have four teeth which includes three premolars that will be lost and replaced and one molar. By the time hunting season rolls around, a fifth tooth may have come in, but the deer is still classified as a fawn at approximately 1/2 year of age. By the time a deer reaches 1 and 1/2 years of age, six teeth will be present but the third tooth should have three cusps (points/projections). This tooth has not yet been replaced with a permanent tooth, indicating an age of 1 and 1/2. However, if the first three teeth appear brighter in color and/or appear to have recently come in, that is a deer that should still be aged at 1 and 1/2.
Photo: Durham Township
Once the third tooth is replaced and becomes an adult tooth, it will change from having three cusps to two cusps. The deer should then be aged at 2 and 1/2 years of age, a point at which lots of changes begin to occur. Now that all of the teeth are permanent, it is necessary to pay particular attention to the tooth structure itself, particularly the wear that is present. In order to get started, you want to locate the first molar, or fourth tooth, in the deer's mouth and look at the teeth moving back from it. On that tooth you want to take into consideration two things, those being the ridges on the outside of the tooth as well as the appearance of enamel and dentine. When a deer is 2 and 1/2 years of age, the ridges on its teeth will bear sharp points. If you look towards the center of the tooth, you will see dark material (dentine) resting next to whiter material (enamel). On a deer of this age, the enamel of these three molars will be wider than the dentine.
By age 3 and 1/2, the fourth tooth will begin to take on a blunter appearance. Dentine will also be at least as wide as the enamel. By age 4 and 1/2, the fourth tooth will continue to become duller and rounder and the fifth tooth will begin to become blunt. Dentine will now be twice as wide as neighboring enamel in both tooth five and six with the rear cusp on the sixth tooth showing heavy wear as well. At 5 and 1/2 years of age, all rear teeth will appear blunt and dentine in the 6th tooth will be wider than enamel. At age 6 and 1/2, the presence of enamel versus dentine will likely not be very visible at all as it will have worn smooth. Teeth will all be rounded and blunt. By age 7 and 1/2, all of this will still hold true except that tooth six takes on a concave appearance. At 8 and 1/2 years of age or more, all teeth will have a concave appearance and be worn smooth, free of ridges.
Although it is possible to get an estimate of a deer's age well into its life, it does become more difficult to be accurate as the animal ages. Diet, too, can play a role in the aging process as it can lead to differences in wear. For example, deer that are feed commercial feeds will experience a slower rate of wear than a deer that forages for food. Ultimately the only way to know for sure a deer's age is to have a record of that exact animal's birth. However, learning to age is still worthwhile and can be a fun and interesting thing to try with your next harvest.
Do you age each deer you bring home? What motivates you to learn more about the animals you harvest? Let us know in the comments.