Determining deer age
Many indicators of deer quality and welfare are related to age. Scrutiny of a deer’s teeth, particularly tooth replacement and wear, is one way for landowners and sportsmen to estimate the age of a deer.
The purpose of MSU Extension Montguide titled, “Determining the Age of a Deer” by James Knight, is to assist those interested in aging deer using tooth replacement and wear techniques. As a deer grows older, certain portions of its permanent teeth, particularly crests of its jaw teeth, wear and expose increasing amounts of dark dentine. Biologists observed this phenomenon and, working with deer of known ages, developed criteria for characterizing age classes based on tooth replacement and wear. They identified most age classes on the basis of the relative amount of exposed dentine on the lingual crests (next to the tongue) of molar teeth. Interest in deer age is more than simple curiosity because many indicators of deer quality and welfare are related to age. If the largest antlered deer are only 3 ½ or 4 ½ years old, they are not living long enough to reach their maximum antler development, which occurs at 6 ½ to 8 ½ years. If older bucks 6 to 8 years are small-antlered, we know there is a problem with nutrition or genetics. Large antlers are dependent on good nutrition, older age and genes. Rarely are genetics the factor that results in smaller- antlered bucks in a given deer herd.
When deer numbers are not in balance with available food, inadequate nutrition causes poor body conditions, reduced reproduction efficiency and undesirable antler characteristics. Body growth needs take priority over antler growth and reproduction in deer of all ages. This means that food shortages affect antler size in males and fawn production and lactation in females before body weights decrease significantly.
The massiveness of antlers generally increase with age but is strongly influenced by nutrition. The number of antler points may increase with age, but it varies considerably with nutrition conditions. A well-fed yearling could be a 4-by-4 buck, but a poorly fed 7-year-old could be a 2-by- 2 buck. Large antlers at an early age reflect good food conditions.