How to Age Whitetail Deer
How to Field Judge Age Whitetail Deer
If you would like for me to be “frank” with you I don’t care how old a whitetail deer is, as long as he’s a trophy animal. I realize that not all regions in the United States hold true to this premise however in the Midwest I have literally seen whitetail deer that were 2 ˝ years old score 150 inches. Its true. Thus if the whitetail that walks by me sports the size rack I desire I could care less about asking him how old he is. However the science of knowing how to age whitetail deer, or knowing how to tell how big old a whitetail deer is can be very important to deer management in regions outside the Midwest as well as in the Midwest dependent upon your management intentions.
Thus over the course of this article we will visit how to age whitetail deer “on the hoof” or in the field so to speak, as well as how to tell exactly how old a whitetail deer is by looking at his teeth in accordance to wildlife biologist reports.
So to follow we will learn how to age whitetail deer in the field as well as how to age a whitetail deer after he is deceased by looking at teeth and other variables.
As the whitetails home area advances in the northern latitudes, it's body weight and size increase. The biological characteristics of this fact is in direct relation to the colder climates of the northern hemisphere. The further north we go in our hemisphere, the physical biological characteristics of whitetail deer get bigger, and vice-versa. Adult whitetail deer body weight can vary dramatically; from under one hundred pounds in parts of southern climates, to over three hundred pounds in the far north.
It is possible that deer can live to be eleven or twelve years old. But most don't live that long. That is because deer wear down their teeth in about ten years at a rate of 1 mm a year. After that they aren't able to eat their food efficiently in which saliva blends with the chewed food that adds active enzymes necessary to the digestive process. When this happens, deer weaken and starve to death. Many die early from predators, injuries, accidents, or disease sustained in daily life. In heavily hunted areas of the country, most bucks don't live much past 1 1/2 to 2 1/2 years of age. Optimum biological deer antler development is attained the 5 1/2 to 6 1/2 years of age.
The fact is the hunter makes the ultimate management decisions as to whether or not the deer lives to grow older and hopefully a bigger rack.
Why is age important? Whitetail bucks as a group tend to produce their very best antlers once they mature in body. With most bucks their skeletal system growth is completed when they are about 4 years of age. Some may be fully mature at 3 and others at 5 years. Up until the time all a buck's bones are completely developed, body development is always going to take precedence over antler development. That's why older bucks, 4 year olds and older produce the biggest antlers.
If you're interested in bucks in your hunting area producing bigger antlers they need to be allowed to mature. But they need be allowed to mature in the presence of good, daily nutrition.
To some degree the genetic potential of a buck can only be determined if he starts and then continues life under ideal nutrition conditions, and is allowed to at least reach 5 or 6 years of age. Of the three major controlling factors in antler development, those being age, nutrition and genetics, the one we need to pay the least amount of attention to is genetics. We as hunters are the ultimate managers and can do something about making certain deer herds are on a good, nutritional diet. This includes keeping herds slightly below the total number of deer a given area of habitat can support even in hard times. It means doing habitat manipulations and possibly planting supplemental forage crops in terms of food plots "to help" over the rough times when quality forage and food is limited due to adverse weather. The quality of deer habitat is reflected in the antlers or mature bucks. Good habitat with sufficient food produces good antlers.
We hunters can also can determine which animals we shoot. Passing up young bucks allows them to get older, some of the time. In some instances, if you pass up a young buck, he well wonder over to the next "pasture" or property and someone there may shoot him anyway. What to do? If you're interested in increasing the average age of bucks taken in your immediate area, start passing up younger deer. But also talk to your neighbors. The reason they may be shooting young bucks is because they're afraid if they pass them, you and your hunting group will shoot them. Talk it over around the fire pit. You just might reach an "understanding" where both hunting groups pass young bucks. These sort of informal agreements have a way of snow-balling. Pretty soon you may have a large area where all the hunters agree to pass up young bucks, and possibly take does instead. This is generally always a step in the right direction to improving the quality of the area's deer herd, and perhaps more importantly the habitat!
Deer age much the same way people age and it's best to think of them in terms of immature, almost mature, mature and old. For the time being forget about antlers. True, like most any other hunter, when I see a deer I look at his head and antlers. Personally, I've hunted a lot of great places and as I have matured I now look for particular antler styles and the overall size of racks, and not particularly what they will score (if I'm hunting areas where bucks have the opportunity to mature in the presence of good nutrition).
After a quick glance at the antlers and making certain both main beams are present, I totally disregard them and look much more carefully at the deer's head, neck and body to determine where he falls within the immature, almost mature, mature and old categories. Besides antlers are generally not a good indication of age, beyond the very young.
Essentially immature refers to yearling bucks, those which are 1 1/2 years old; almost mature refers to the 2 1/2 and 3 1/2 year olds; mature refers to the 4 1/2 to about 6 1/2 year olds; and old to those 7 1/2 years old and older. Unfortunately in a lot of whitetail country, hunters even today will see hardly any bucks that could even be classified as mature. But thankfully things are changing.
Yearlings, or immature bucks have slender necks and bodies. They remind me of looks and behavior of 12 to 15 year old boys. And their hocks (tarsal glands) are usually cream-colored during the rut.
Notice that the rack (antlers) is not depicted above as an indicator. While some very general statements can be made about antler developmental characteristics at certain ages of a buck, the rack is the least reliable of any indicator. Remembering that these statements have MANY EXCEPTIONS, antlers generally gain mass as the buck ages, generally get darker as the buck ages, generally get wider as the buck ages, and will get any nontypical points in it's genetics once the buck has matured body wise. So, if a buck's antlers are wider than it's ears, dark in color, seem thick in the beam circumferences, and have some nontypical points, chances are good that the buck is mature. Because of the tooth wear, a post mature buck's rack may actually start getting smaller from year to year, but they usually keep the basal circumference, then it will thin out quickly from there.
Many people think they could never mistake a buck fawn for a doe, but every year we have too many of those same folks wind up doing just that. On the head, the pedicels (nubs) are the most obvious clue. The ears will appear long, and the nose will appear short. The body will be smaller than the adult doe's, but is bigger than a doe fawn, so be careful. The legs look long and skinny, and the gait is usually frisky, often frolicking. The tarsal glands will be small and snow white. Does seldom travel alone, so give it a few minutes to see if more deer show up for comparison. I've seen many buck fawns by themselves.
When attempting to age deer in the bush, the nutritional status of the animals must also be considered. For example, in South Texas, periodic drought negatively impacts antler development due to the sub-par range conditions they create. Thus sportsmen employing antler size criteria to complement their age estimate in this region must pay particular attention to weather conditions during the spring and summer antler-growing periods.
In dry years with poor range conditions, average antler size will drop significantly, resulting in underestimating a buck's age. Worst yet, prime-aged bucks can be harvested because hunters consider the animals inferior (antler-size-wise) for their age and remove them for what is often referred to as management bucks, whereas if passed over, these bucks could develop exceptional antlers in proceeding years under ideal conditions.
Three characteristics are employed to estimate age of live bucks. These include antler size, body characteristics, and behavior. The following is an overview of characteristics that can be employed in the field to age whitetails on the hoof.
Lets forth definitions of teeth as to further understand the basis by which you age a whitetail deer by its teeth.
1 AND 1/2 YEARS
Field Judge Age Whitetail Deer
At this age, a buck looks like a doe with antlers. There will usually be a slight dip in the back. They have a thin neck, no defined brisket, white tarsal glands, and the belly line has a distinct up turn near the hams. This gives it a greyhound racing dog sort of look. The legs still look very long, and the gait is still pretty frisky. They will make unwanted sexual advances on does, but are very timid in the presence of older bucks. A yearling buck can be described as a doe with antlers. Ears are semi-pointed at the terminal end, and the nose is well defined and square in appearance. Their legs appear long and thin because their body is slim. Yearlings will not develop a swollen neck or the muscular features of older bucks. Although fawns rub tarsal glands, a yearling's tarsals remain small and tan in color. In the relaxed or semi-alert position, the tip-to-tip measurement between the ears is approximately 14 inches. Seldom will a yearling buck exhibit an outside antler spread over 14 inches. The number of antler points is not a reliable feature when estimating age. This is especially true in nutritionally strong deer habitat and in supplementally fed herds where yearlings commonly produce six, eight, or even 10-point antlers. Fawns have less than six teeth. MOST FAWNS IN NOVEMBER HAVE FOUR CHEEK TEETH, because they were born in June and are five months old. They fall, therefore, into the four-seven months age class. Fawns less than four months will have only three cheek teeth, and fawns over seven months will have five cheek teeth. The front teeth of deer are not important in determining age because all four pairs are replaced by eleven months of age. They do help to break down the four-seven month age class, however, fawns less than five
2 AND 1/2 YEARS
Field Judge Age Whitetail Deer
At two and a half, the animal starts bulking up a tad, but just a tad. The neck will be bigger than a doe or yearling buck, but not much. The legs still look fairly long. The face looks long and the skin tight. Eyes are near perfectly round. Slightly developed brisket. The belly still has somewhat of an upturn near the hams. The tarsal gland may have some color to it. The rump appears squared off. 2 1/2-year-old bucks are more muscular in chest, but not as much more in hams than a yearling, but they will have a large neck near the rut. In fact, the easiest way to identify a yearling from a 2 1/2 is the neck. If it has a big thick neck, it is not a yearling. At two years of age, antlers are not large, but can make you take a second look. They are larger than yearlings, but their legs remain long in proportion to their body. Their belly remains firm with no sag whatsoever. During the rut, neck swelling is minimal. The tarsal glands begin to get darker in color, but obviously less than older males. When observed broadside, the head appears elongated. Deer in the 19 month class can be confused with 2 1/2 year old deer because both have six permanent cheek teeth which are relatively unworn. However, the 19 month old deer will have no wear on the rear peak of the last tooth, and the first three teeth will be relatively unstained and possibly not fully erupted. The 2 1/2 year old deer have sharp peaks on all of the cheek teeth and very little wear on the last tooth.
3 AND 1/2 YEARS
Field Judge Age Whitetail Deer
A three and a half year old buck reminds me of a racehorse. They are usually very lean muscle, and act ready for action. They may make rubs and scrapes if no bigger bucks are present. The nose lengthens and broadens, The head will look as long as it's going to look during their life. Eyes are still very round. The brisket is noticeable but not pronounced. Legs look the right length now. The belly line is flat, with just a little up turn at the rear. The tarsal gland will be dark in rut. Rump starts looking more rounded at times and squared off at times, depending on stance. Back line is flat. 3 1/2-year-old bucks look very much like thoroughbred race-horses. Very trim waist, but shoulders and hams are very muscular. Middle-aged bucks portray a muscled neck and deeper chest, yet a distinct junction between the neck and shoulder exists. Some describe their appearance as that of a well-conditioned racehorse. Muscling absent in 2.5-year-olds begins to become obvious in the third year. Their chest begins to appear as large as their rump. Antler spread is often outside the ears and on quality habitat impressive antlers can develop. For inexperienced individuals, three-year-olds are often mistaken for mature bucks. These older deer are aged by the amount of wear on the cheek teeth. The 3 1/2 year olds begin to show wear on the peaks of the fourth tooth, and the peaks will have a brown center. The last cusp on the rear tooth will be worn into a shallow cup shape.
4 AND 1/2 YEARS
Field Judge Age Whitetail Deer
If fed well, a 4 and a half year old buck really starts looking like a buck. The giveaways now are the back and belly lines, and the head. On level ground, the back will have a slight dip only, and the belly will not hang below the chest line. The head skin will not look tight or loose, and the eyes aren't quite round anymore. When one of these bucks walk, they still pick their feet up pretty good, and the front knees won't look bent in when the deer is walking toward you. Rump is getting pretty round, and tarsal glands will be black when near or in rut. Nontypical points may start to show up now. 4 1/2-year-old bucks are really at the peak of their game. Muscular in hams and shoulders, but belly is starting to get big, with some sag. The neck of a 4 1/2 is so large it kind of blends straight into the chest with little definition between the two, as in no destinct line between the end of the neck and the beginning of the chest. Bucks mature at four years of age and lose the racehorse appearance. The obvious junction between the neck and the shoulders fades away as the neck becomes firmly muscled, appearing almost as large as the chest. The animal is muscled throughout, but their stomach remains taut, yet rounded, and their back remains flat. The legs begin to appear shorter and no longer out of proportion. Antlers can be large, as they have attained 90% of their size. The tarsal glands become noticeably larger and darker, chocolate to black. Behaviorally, four-year-olds are the most aggressive and active age class during the rut. Very old deer are relatively easy to recognize because all the teeth are worn flat and nearly into the gums. It is the deer between 3 1/2 and 6 1/2 years which are difficult to age and require considerable experience.
5 AND 1/2 YEARS
Field Judge Age Whitetail Deer
This one gets hard to pass up. Unless your herd is well managed, most bucks don't make it to this old, but you should actually let a buck get at least 6 before you hammer them to achieve maximum antler potential. Now, the eye will obviously not be round anymore, it starts to look squinty. The brisket is obvious where it joins the neck. The belly hangs even with the chest or starts to hang below it a bit. They start walking a bit knock kneed. They seem more deliberate in their actions. Skin on head starts looking a bit loose. Often have nontypical points. 5 1/2+ year-old bucks have a lot of belly sag and the back starts to become swayed. Neck is huge with no definition between neck and chest. At this age bucks are approaching their maximum antler-growing years, thus antlers can be large yet indistinguishable from genetically superior four-year-old males. The principal characteristic defining this age class is an obvious sag in the stomach and a slight drop in the back. The nose is often rounded, losing the square confirmation characteristic of younger males. Their legs appear thicker as well. During the rut their necks are extremely muscled, inflated-like in appearance, eliminating the juncture between the chest and neck. The neck and brisket area appears to become one. Five-year-olds are in peak muscular condition with little sign of aging. The tarsals on some become obviously chocolate brown to wet-black, oftentimes extending down the entire inside of their legs. One other characteristic. Often at this age bucks will start to develop narrow, squinty eyes. Watch for it.
6 AND 1/2 YEARS
Field Judge Age Whitetail Deer
When a six year old walks out, it's usually pretty obvious who is boss. All other deer pay attention. He is on top of his game and knows it. Actions are very deliberate, like a big bull swaggering in. The front knees bend in to handle the weight of the neck and rack. The belly and back sags from years of fighting gravity. When relaxed, the ears tend to droop down a bit for the same reason. The rump is well rounded. The brisket obvious. Eyes are squinted; almost mean looking. With good nutrition, all nontypical points in his genes will pop out now. This is what you've waited for. TAKE HIM! Lucky is the hunter privileged to see a buck that has reached what is referred to as its golden antler producing year. At six, their physical appearance is similar to five-year-olds; however, one distinguishing feature to look for is obvious loose skin protruding from under the lower jaw. The nose is rounded and the ears no longer terminate to a sharp point. A prominent rounded belly and a sagging back also become obvious. Although deer develop their largest antlers at six years of age in South Texas, it doesn’t mean that all six-year-olds will exhibit extremely large antlers because of variable factors such as weather conditions (rainfall) and the animal’s genetic potential, which ultimately determine antler size.
Field Judge Age Whitetail Deer
These over mature bucks are extremely rare and sometimes confused for younger deer because their muscular features begin to regress. Loose skin around the face and neck is obvious. Ears are completely rounded at the terminal end with old, healed-over scars sometimes evident. As these animals reduce their breeding activities, recent battle scars are not present but old healed-over scars are evident. Although antler size generally decreases in the over mature age classes, I have witnessed exceptional antler growth in older bucks experiencing ideal range conditions. Matter of fact, I harvested an 8.5-year-old (based on tooth wear) buck in 1993 that gross scored 184 and netted 171 3/8 inches. Thus antler size alone cannot always be employed to estimate a deer’s age. Behaviorally these deer are extremely reticent and often go unobserved until peak-rutting activity is over.
Aging Whitetail Deer by Teeth
Type of Whitetail Deer Teeth:
Premolars. The first three small jaw teeth. These are used for cutting the food. These are labeled P1, P2, and P3 in the diagram.
Milk Teeth. Temporary premolars that are later replaced by permanent one.
Enamel. The hard, white outer coat of the tooth.
Dentine. The soft darker inner core of a tooth.
Lingual Crests. The sharp taller tooth ridges running front to back on the tongue side of the jawbone.
Buccal Crests. The sorter tooth ridges running front to back on the check side of the jawbone.
Infundibulum. The dark central depression between the buccal and lingual crests of the teeth.
Back Cusp. The shelf like surface on the very back of the last molar.
Incisors. The four tiny cutting teeth at the front of the lower jaw.
The only way to truly tell the age of a deer, is to examine the teeth. Deer are born with four teeth on their lower jaw. These four front teeth are called incisors. After a few weeks, sixteen more teeth grow in, giving it eight front incisors, six premolars on the bottom jaw, and six premolars on the upper jaw.
When the deer is one year old, six more molars erupt on both the upper and lower jaws. This gives the deer a full set of 32 teeth. The darker material in the tooth is called the dentine. As the hard enamel is worn away, more dentine is visible.The amount of visible dentine is an important factor in determining the age. The tooth wear and replacement method is not 100% accurate however, due to the differences in habitat. Tooth wear on a farmland deer may not be as fast as that of a deep woods buck.
The most accurate way to tell a deer's age is by removing a tooth, cutting a cross section of it, and counting the rings under a microscope, (much like aging a tree). Each winter, when a deer's blood-serum protein and phosphate levels are low, a layer of cementum is formed on the tooth. Therefore the tooth has one layer for each winter the deer has lived through.
Six Months: Aging Whitetail Deer by Teeth
The nose or muzzle of the deer appears short or stubby, when compared to older deer. The central two incisors may still be erupting. Incisors may appear twisted as they emerge through the gum. Generally, there are only four cheek teeth showing. The third premolar has three cusps. The black lines on the teeth below indicates where the gum line was.
1-1/2; Years: Aging Whitetail Deer by Teeth
All permanent front teeth are in. Six cheek teeth are visible in the lower jaw. The third premolar may still have three cusps, or the permanent third premolar may now be in (two cusps). Third molar may still be erupting through the gum. Lingual crest of molars have sharp points. Inset: Extremely worn third premolar may fool people into thinking deer is older. Actually, this tooth is lost after 1-1/2; years and replaced with a permanent two-cusped premolar.
2-1/2; Years: Aging Whitetail Deer by Teeth
All permanent premolars and molars are in place. Look closely at the fourth cheek tooth (first molar). The cusps are sharp and show little or no wear. Enamel (white portion) of the lingual crest shows well above the dentine (brown portion). The enamel portion of the cusp is wider than the dentine. Some wear on third cusp of sixth cheek tooth (third molar).
3-1/2; Years: Aging Whitetail Deer by Teeth
Lingual crests of cheek teeth show some wear and cusps are starting to become blunt. Dentine now thicker than enamel on cusp of fourth cheek tooth (first molar). Dentine of fifth cheek tooth (second molar) usually not as wide as enamel. Last cusp of sixth cheek tooth is flattened.
4-1/2; Years: Aging Whitetail Deer by Teeth
Lingual crest of fourth cheek tooth (first molar) is gone. Crest of cusps on fifth and sixth cheek teeth (second and third molar) are blunt. Dentine of fourth cheek tooth now twice as wide as enamel. Dentine of fifth cheek tooth wider than enamel.
5-1/2; Years and older: Aging Whitetail Deer by Teeth
In most hunted deer populations, less than two percent of the animals are more than five years of age. Accurately aging these deer by tooth wear is usually more of a guessing game than a science. In general, deer close to 5-1/2; years of age will show considerable wear on the premolars, and the first cusp of the fourth cheek tooth (first molar) will be dished out or show signs of "cupping."
More recently, a technique of aging teeth by cementum annuli counts has been developed. Alternating light and dark layers of cementum can be seen on microscopic sections of deer incisors. These cementum annuli are much like annual rings of trees. The system is more accurate than the method described above. Biologists routinely collect one or both of the center pair of incisors from hunter-killed deer at check stations for age analysis. The preparation of tooth sections is a laboratory procedure and incisors must be routed to the Wildlife Research Center in Columbia, Missouri for processing. Again I say while field judging the age of whitetail deer is extremely interesting and pertinent to deer management, I would shoot a big 2 year old Midwestern Buck scoring 150 inches if presented with the chance rather than trying to take an older buck that might score less based upon genetics.
By aging whitetail deer by teeth you will be able to determine genetics and nutrional needs that are being met in your area.
I hope this article has helped you in regard to aging whitetail deer.