Although whitetail deer can live to be older in captivity, they can also live a relatively long time in the wild. The longest living wild whitetail that I have heard about was almost 16 years old! Whitetail are primarily born in late May and early June. Therefore, when most deer are harvested in November they are either six months, 1 1/2 years, 2 1/2 years, 3 1/2 years, etc. in age. Aging deer accuratley is important for proper management.
The overall age structure of a white-tailed deer population is younger than most people think. There are some states where the average harvested deer’s age is 1 1/2 years old. It has often been thought that antler and body size can indicate a deer’s age, but physical characteristics can often be quite misleading.
Before we start you must first understand that the number of antler points in no way corresponds to the age of a deer. Even if it did work that way, it would not help wildlife professionals in aging does. Antler size in bucks and physical development in both genders is greatly affected by diet and genetics, which may account for differences between animals of the same age taken from different locations.
The only true way to measure age in whitetail is by a deer’s teeth. The science of aging deer is based on tooth development and wear. Like humans, deer replace their baby teeth with permanent teeth at a relatively set rate. A buck will be in the process of losing its third premolar at 1 1/2 years of age. By the time a deer is 2 1/2 years old, all permanent teeth are in.
After a deer reaches 2 1/2 years old, age estimation is based largely on the rate of tooth wear. Diet and soil types may accelerate tooth wear, or not. However, estimating the age of adult deer follows a routine pattern until they are about 5 1/2 years of age. Once extreme tooth wear takes place, aging deer accurately based on tooth wear becomes less reliable. Of course, very few deer older than 5 1/2 are examined on an annual basis.