The Importance of Aging Deer

As a biologist and hunter interested in quality white-tailed deer management, there are a few questions people always seem to ask me: “What do you think he’ll score?” This is usually followed by their second question, “How old is he?”

Although these are both good questions, they usually are not asked in the proper order. The very first question you should ask before pulling the trigger is “how old?” For any hunter that is interested in harvesting a mature whitetail buck, the best way to improve the odds is to pass on harvesting good young and middle-aged deer. If you aren’t willing to let them live another year, how then do you expect to shoot a larger buck? Luck?

Estimating the age of deer can be hard. This can be especially difficult if the buck is a hundred or more yards away, the deer is obscured, moving, and the hunter is trying to make up his mind as to whether or not to squeeze the trigger.

The Importance of Aging Deer

The fact is that hunters make the ultimate management decision as to whether or not the deer lives to grow older, and ideally gets older and grows into a bigger deer with a larger set of antlers. It’s not THE goal for every hunter, by no means, but many hunters desire bucks with larger antlers. The most direct way to achieve this goal is to let deer age, get older. This is why aging a deer on the hoof is important. In general, letting bucks get older will allow them to get bigger. However, not all bucks will reach 150, 170, or 200+ inches on the Boone & Crockett scoring system.

Why is age important you ask? Whitetail bucks as a group tend to produce their very best antlers once they mature and complete their long-bone growth. With most bucks, their skeletal growth is completed when they are about 4-years of age. It varies though. Some bucks may be fully-mature at 3 and others at 5-years old.

Until a buck’s bones are completely developed, body development will always take precedence over antler development. Now you can appreciate why bucks produce bigger antlers as they age and the largest-antlered bucks tend to be the biggest-bodied.

If you want whitetail bucks in your area to produce bigger antlers they need to be allowed to mature. In addition, they need good nutrition, which can be provided through good habitat management and even supplemented through a feeding or food plot program.

Providing good habitat includes keeping deer populations at or below the carrying capacity a given area of habitat can support. Bucks with good genetic potential will never grow big if they don’t have enough to eat! Ever notice that the biggest bucks always seem to come from areas with a low deer density?

The quality of deer habitat is reflected in the antlers of mature bucks. Good habitat with sufficient food produces good antlers. You can see this phenomenon between “drought” years and “wet” years. During dry years, bucks will have lower body weights and antler quality will be below average for age classes, but during years of abundant rainfall deer will be larger and have larger antlers. Managing deer is about manipulating both habitat and deer for optimal or high quality conditions year after year.

Hopefully, I have given you a better understanding of the important of aging deer in the field. Removing a great 3 1/2-year old buck will not allow you to harvest a truly awesome 5 1/2-year old later. Pass on him and take an inferior buck or a buck that has reach his maximum potential (which may not be that impressive). Base your shots on age AND antler size, not just antler size, and you will see the difference within just a year or two.

Aging White-tailed Deer on the Hoof

Learning to estimate the age of a white-tailed deer on the hoof is an invaluable skill for any serious deer hunter or manager, especially as it pertains to buck harvest. Whether you want to estimate the age structure of the whitetail population found on a property or want to make specific determinations regarding the harvest of particular bucks, it takes time to get good at aging live deer. This article is designed to start you on the path to accurately aging deer on the hoof.

Aging deer on the hoof

Most hunters do not have access to free-ranging deer of known ages, so this makes the learning process more difficult, but not impossible. Just about everyone is using motion-triggered cameras nowadays and these game camera photos provide excellent opportunities to practice. Whether you use your trail cameras to conduct surveys to estimate your deer population or just to gather snapshots of bucks using the area, accurately estimating ages is paramount to assessing the progress of a management program.

Aging of Bucks is Important

Harvesting bucks at the optimal age is an important aspect of white-tailed deer management. Research and experience has revealed to biologists that whitetail bucks reach maximum antler growth between 5 and 7 years of age. There may be some hunters that insist on allowing bucks to get even older (and sometimes bigger), but annual mortality is always an issue with bucks, especially once their mature.

From my experience, free-ranging bucks that are 5 years old are old enough and will not increase substantially in antler size. Furthermore, research has found that a 4 year old (whitetail) buck’s antlers represent 90 percent of the buck’s potential for total antler growth. You will have some really good bucks even if the goal for the property/deer you manage is to get them to 4 1/2 years of age.

Aging Deer on Hoof

Besides, if you’re managing for 4 year old bucks then you will undoubtedly have some 5+ year old bucks on on your hunting grounds. Once a buck grows older he gets a bit smarter too, so he may become a live target at 4 years old but  drop off the radar come hunting season, only to re-emerge a year or two later, if you’re lucky.

Regardless of whether the goal is to harvest bucks that are at least 4, 5 or 6 years of age, it still takes hunters that are proficient at aging deer on the hoof to get there. Dead bucks don’t get any older.

Deer Management Means Learning to Age Whitetail

Whether you plan on harvesting bucks at 3 1/2 or 6 1/2 years of age you need to be able to estimate the age of deer on the hoof. The ability to rank a buck’s antler quality (compared to his peers) depends on property aging, too. There are three factors that influence antler size and development in whitetail bucks: age, genetics and nutrition.

The age of a buck is important for developing quality antlers and must be considered in combination with nutrition with some amount of genetic input. In fact, I find many properties are focusing way too much on genetics when efforts would better used enhancing deer habitat and simply allowing bucks to get older before they are shot.

The majority of hunters would be tickled pink to shoot a mature buck on quality habitat. It takes active management to provide good cover and food, as well as having a trigger finger that exhibits patience.

Improve Deer Aging Skills Through Backtesting

It’s not easy to age free-ranging deer when you’re starting out, but you can greatly improve “target recognition” through backtesting. This involves using game camera photos of bucks that you or others have harvested previously, off of your hunting grounds. Deer body sizes vary from place to place, so you want to learn using the deer that you will be hunting. It would not help much your management program if you could accurately age deer in Central Texas but were managing deer in Ohio. They look completely different.

Key points for aging deer on the hoof include:

  1. Shape of head – a mature buck’s appears short, deep
  2. Body size – younger bucks are thin, doe-like
  3. Neck – fills out deeper into shoulders as bucks age
  4. Depth of body – deeper body on older bucks
  5. Leg length – older bucks appear short-legged

Start a backtesting program on your hunting lands by maintaining game cameras prior to the hunting seasons. As bucks are harvested, age the bucks based on tooth wear and replacement. Over a few years you will start to get a good handle on what bucks of different ages look like. This is especially helpful when particular bucks can be tracked over several years.

Aging Bucks on the Hoof

Say a deer is shot at 5 1/2 years of age, well then if the buck is readily identifiable you can go back to your photo vault and see that same deer in prior years, say at 3 and 4 years of age and see how his physical and antler characteristics have changed.

Of course, I must mention that aging deer based on tooth wear is not an exact science either, as wear also varies from area to area based on soils. The teeth of deer that live in sandy soils wear down faster than the teeth of deer living on clay soils. The overall idea is to use tooth wear from harvested bucks and physical characteristics of those deer in photos to build the best photo library of “known-age” deer on your hunting grounds.

Aging Deer in the Field: It’s Not Perfect!

Aging deer on the hoof is an inexact science, but it’s all that we’ve got. Aging deer accurately beyond 2 1/2 years of age based on tooth wear (with the jawbone in hand) can be tricky enough for those just starting out, but estimating the ages of live deer in the field can be downright difficult.

My advice is to be patient and get photos of the bucks in your area prior to the hunting season. Start by sorting bucks captured on camera into groups such as young (1-2), middle-aged (3-4) and mature (5+ years old) and then see how those estimates play out come hunting season, once those deer are tagged.

As you will see, aging deer is not always clear-cut. Whether you are exactly right is not as important for your deer management program as whether or not you, or the other hunters where you hunt, can differentiate between older deer and high quality younger bucks with a lot of potential. Mistakes will always be made, so don’t waste them, learn from them.