ANR-561, Reprinted December 1996. By H. Lee Stribling, Extension Wildlife Scientist, Associate Professor, Zoology and Wildlife Science, Auburn University.

Alabama White-Tailed Deer: Collecting Herd Management Information

Deer hunting has become the most popular form of hunting in Alabama, with more than 200,000 individuals hunting deer in the state each year. Many landowners, deer hunters, and organized hunting clubs want to take an active role in deer management on the properties they own or hunt.

Different people want different things from the deer that they hunt. Some just want to observe the deer when they go hunting. Others want to see deer in good condition, even if they see fewer animals during the season. There are also those who would like to see a "trophy" buck, even if he is the only deer they see all year. Depending on the objectives of the particular landowner, hunting club, or individual, deer herds can be managed specifically to meet these goals.

Collecting Herd Data

In order to design the harvest to meet your management objectives, you must collect information from each deer harvested on your particular tract of land. To determine if your deer herd and habitat are in balance, collect and record the following information on each deer:

• Identification number.
• Date of harvest.
• Sex of deer.
• Weight of deer.
• Number of antler points.
• Jawbone.

Data Sheet

A data sheet provides a standard format for the information you collect. It helps ensure that all the necessary information is collected from each deer and that it is recorded in a consistent manner.

Identification Number. Assign a number to each deer harvested. Number the deer consecutively to simplify record-keeping. Record the number on both the data sheet and the jawbone so that the information and the age can later be matched correctly.

Date of Harvest. Record the date when the deer is harvested.

Sex of Deer. Bucks are heavier than does. The sex of the deer must be known in order for the weight data to be meaningful. The ratio of bucks to does in the harvest is important.

Weight of Deer. The weight of the deer must be determined using an accurate scale. Scales can be purchased for less than $50 from a forestry or sporting goods supply house. Recording accurate weights is very important for determining if an area is over- or underpopulated.

Biologists know, for instance, that 1-1/2-year-old bucks in some parts of Alabama can average 130 pounds if the deer are not overcrowded. Weight, combined with the age and the sex of the deer, will tell a biologist whether to increase or decrease a deer population to keep it in balance with the habitat and the hunter's or landowner's objectives. The deer's live weight is more helpful than its dressed weight. However, live weight can be estimated from dressed weight by using the graph below.

Antler points. Record the number of points on the deer's antlers. Some people also like to record the spread (the widest distance across the antler) and the length and circumference of the main antler beam. The circumference is the distance around the main beam 1 inch above the antler base.

Jawbone. The age of a deer is determined by tooth replacement and wear on the jaw teeth. In order to age a deer using the teeth, you must remove one side of the lower jawbone. Some people just cut the jawbone out using a knife or a saw. However, the following procedure is easier and quicker, and the jawbone comes out more cleanly.

Extracting The Jawbone

To extract a jawbone, you will need a pair of long handled pruning shears and a jawbone puller. These can be purchased from a forestry supply company. The shears can also be found at most hardware stores, and you can have a welder make the puller using the dimensions shown in Figure 2.

Removing one of the jawbones is a fairly simple process. Figures 3 through 6 show the steps involved. This process is safe even if you plan to have the deer head mounted. Taxidermists do not object to taking a deer head with a jawbone removed because it is not used in mounting.

1. To extract a jawbone, you need pruning shears and a jawbone puller. See Figure 2.

2. If the deer's jaw is locked shut, use the jawbone puller to pry open the mouth. See Figure 3.

3. Use the jawbone puller to loosen the muscles and membrane between the teeth and cheek by inserting the puller and twisting. See Figure 4.

4. Use the pruning shears to cut the jawbone. Insert the narrow side on the cheek side of the mouth. Be careful not to break the tops of the back teeth. See Figure 5.

5. After cutting the jawbone, insert the smaller, rounded end of the puller through the cut. With your fingers, push the back point of the lower jaw through the small end of the puller. See Figure 6.

6. Anchor the deer's head by placing your foot across the throat and give the puller a quick tug. The puller will slide along the bottom edge of the jawbone, breaking the connective tissue. Separate the two jawbones in the front where they meet.

After you extract the jawbone, clean it by scraping away all muscle and tissue with the edge of a knife. Dry the jawbone with a cloth. Using a permanent marker, write the deer's identification number on the jawbone. Store the jaw in a dry, open place away from rain and where no animals can get it. A fish basket suspended from a rope in a shed is a good place.

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Determining Age From The Jawbone

You can determine the age of a deer by examining the jaw teeth for wear and replacement. This technique is fairly simple and accurate. With a little practice, almost anyone can age a deer by looking at the jawbone.

Save jawbones from deer of different ages to use for comparison and for teaching others how to age deer. Some people even mount a set of jawbones on a board and keep them with their herd management records for quick reference.

Deer are aged in 1/2-year fractions because they are born in summer and usually killed in winter. Deer, like human beings, have baby teeth (milk teeth) and adult teeth. Fawns have three baby jaw teeth, and adult deer have six jaw teeth.

By knowing when certain baby teeth are re placed, you can tell the age of young deer (less than 2-1/2 years old). After this age, all the baby teeth are gone, and you must look at tooth wear to determine age.

Deer teeth are made of two materials: enamel, the light-colored substance covering the outside of the tooth, and dentine, the dark-colored substance inside the enamel layers. Since the dentine is wider at the base of the tooth than at the top, more and more dentine shows as a deer's tooth wears down. A comparison of the width of the dentine with the width of the enamel indicates the deer's age.

In some areas of the state, wear occurs at a more rapid rate than in other areas. Keep this difference in mind when aging your deer. For example, deer that feed on agricultural crops in sandy soils pick up a lot of sand as they eat. Because of the sand, their teeth wear down faster than the teeth of deer feeding in less sandy soils or in non-agricultural areas.

This chart shows the jawbones of deer of various ages. Compare your jawbone to these drawings to determine the deer's age.

Analyzing The Data

A wildlife biologist can analyze the data you collect and then make recommendations to help you achieve your herd-management goal. The biologist may advise you to harvest more or fewer deer next season, harvest only deer of a certain size, or maintain a certain ratio of bucks to does in the harvest.

Collecting accurate information about your deer herd is the only way you can reach your deer management objectives.

Assistance with analyzing deer data is provided free of charge by the Alabama Department of Conservation and Natural Resources, Division of Fish and Game (242-3469). Assistance is also available from private wildlife consultants across the state and from your county Extension office and the Extension wildlife scientists at Auburn University.

Some information in this publication was taken from the following publications:

Davis, James R. 1979. The white-tailed deer in Alabama. Alabama Department of Conservation and Natural Resources, Special Report No. 8.

Marburger, Rodney, Jack Ward Thomas, and B. D. Loving. A tale of teeth. Texas Game and Fish Magazine, November 1964.

Key To Jawbone Comparison Chart

Fawn. A fawn's jaws are very small and have only four teeth.

Yearling (1-1/2 years old). Yearlings are the easiest to recognize. The first three jaw teeth are milk teeth. These will be worn smooth, while the remaining teeth (numbers 4, 5, and 6) will be sharp. Tooth number 3 will have three cusps (points) if it is a milk tooth. It will be replaced when the deer is 2 years old with a two-cusp adult tooth.

2-1/2 years old. The first three milk teeth have been replaced by adult teeth. The number 3 tooth has two cusps. All teeth are sharp. On the tongue side (the higher side of the tooth), the dentine of the number 4 tooth is not as wide as the enamel which surrounds it.

3-1/2 years old. The dentine of tooth number 4 is wider than the enamel, but this is not true of tooth number 5.

4-1/2 years old. The dentine of tooth number 5 is wider than the enamel, but this is not true of tooth number 6.

5-1/2 years old. The dentine of all three back teeth (4, 5, and 6) is wider than the enamel.

6-1/2 years old. Tooth number 4 is worn smooth, but teeth 5 and 6 are not.

7-1/2 years old. Teeth 4 and 5 are worn smooth, but 5 may have a slight ridge remaining.

8-1/2 years old. All three back teeth (4, 5, and 6) are worn smooth, but 6 may have a slight ridge remaining.

Over 8-1/2 years old. It is generally impossible to determine the age of a deer older than 8-1/2 years from the jawbone, because all of the characteristic formations have been worn smooth.