There’s more to a deer’s appearance than mere aesthetic beauty. Most aspects of a deer’s distinctive ‘look’ are adaptations geared to ensure the animal’s survival and successful reproduction. (Micheal Heston/Special to The Herald)
Just what sort of woodland creature is the white-tailed deer? What exactly is this animal we seek so avidly when we go afield?
“Deer were abundant in the South long before the white man made his appearance,” said wildlife biologist Bill Gray. “Today they are admired for their physical appearance by hunters and non-hunters alike, but many fail to understand that the characteristics contributing to their beauty are really mechanisms for survival and reproduction. For example, their large ears and big “soulful” eyes give them keen senses of hearing and sight. Their long legs enable them to move quickly to evade predators. The antlers of male deer are formidable weapons, especially during the rutting season. Each aspect of a deer’s physiology makes it one of the world’s most resilient and adaptable animals.”
According to Gray, deer depend on motion and depth perception to identify objects by sight. With their large eyes they are even able to detect motion behind them along their flanks. They are more suited for seeing in low-light conditions than in bright sun and their color perception is like that of a human who is red-green color blind. Hence, their preference for moving about during early morning or late-evening hours.
“A deer’s sense of hearing is very acute as well,” Gray explained. “Their large, movable ears allow them to detect sounds at a great distance and quickly pinpoint the direction those sounds are coming from. Deer also use their acute sense of smell to detect danger. It’s often said you can fool a deer’s eyes and ears, but fooling its nose is all but impossible. Other functions of the deer’s olfactory sense include identification of other deer and favorite food sources. Researchers have identified seven specific glands in white-tailed deer, most of which are used almost exclusively for scent communication.”
Gray points out that the hairs of a deer’s winter coat are hollow and provide excellent body heat retention. Since such insulation is not needed during the summer months, the deer sheds this thick, brownish-gray winter coat for a thinner reddish one that allows more heat to escape. Spring fawns are born with spotted coats to break up their outline and conceal them from predators.
Female deer are smaller and weigh much less than males. At shoulder height, an adult doe stands about 36 inches on average. Bucks are slightly taller. Weights of healthy adult does range from 90 to 140 pounds while healthy bucks at maturity can weigh 140 to 200-plus pounds in this part of the country.
“Whitetail bucks grow a set of antlers each year,” said Gray. “Antler size depends on age, genetics, and nutrition. Healthy, well-fed bucks grow a progressively larger set of antlers annually through their prime age (5.5 – 7.5 years). Antler growth is triggered by day length and the secretion of various male hormones. Antlers typically go through a growth period from April to September and are normally shed in late winter and early spring. Mature whitetails use their antlers for defense, leaving ‘rubs’ associated with breeding activity, and for fighting with other bucks during the rut.”
According to Gray, research suggests that deer may naturally be most active during the nighttime hours. While whitetails will move about during daylight, they are not prone to do so as much. Typical daily movement patterns can be affected by weather, availability of food, disturbances, sex, age, and reproduction. Bucks may increase their daily movements during the rutting cycle while does may reduce their moving about late in the gestation period.
“Another aspect of deer behavior is vocalization,” Gray said. “Several different deer sounds have been analyzed and identified. The snort is the most recognized of these sounds. Deer also make a shrill, whistling sound when alarmed that is often accompanied by the stamping of a front hoof.”
Male deer display a unique set of behaviors between the period of antler hardening and breeding. Rubbing, sparring, scent marking, and scraping are prevalent during this time. Intense fighting occurs well into the breeding season and is the result of competition for breeding opportunities and social standing. Deer herds have definite social hierarchies among both sexes.
“Except for the breeding season,” said Gray, “adult males and females maintain little contact throughout the year. Bucks typically form small bachelor groups and does gather with female offspring from the previous year along with the current year’s fawns. Shortly before giving birth, does will drive away older fawns that may rejoin their mothers and the new fawns later in the fall. Adult does in good physical condition usually produce twin fawns each year. One fawn of each sex is the norm.”
In well-managed herds, there is a good proportion of older-age-class bucks. Deer herds with a good ratio of mature bucks function more naturally in terms of social interaction and breeding behavior.
“Deer herds receiving heavy buck harvests and insufficient doe harvests generally have poor age structure among bucks and have reduced fawn production,” Gray explained. “Such herds contain few mature bucks and often display poor overall herd health.”
The challenge, according to Gray, in modern deer management is to maintain the proper size and structure of populations so the animals are healthy and their behavior is normal. Under those conditions, local hunters can enjoy the benefits of white-tailed deer for many generations to come.