Scientific name: Odocoileus virginianus
Family: Cervidae (includes deer, elk, moose, and caribou)
Subspecies: There are 38 subspecies of white-tailed deer in North America and South America. The subspecies that occurs in Illinois is Odocoileus virginianus borealis.
Distribution: The distribution of white-tailed deer covers parts of Canada, much of the contiguous United States, Mexico, Central America, and the northern part of South America. White-tailed deer are found throughout Illinois.
Physical Description: Due to the abundance of food and the generally mild winters, deer in Illinois do not need to migrate and they are typically in good physical condition. This leads to strong yearly reproductive and survival rates—females often have multiple fawns, and most of the adult deer survive the winter.
Deer vary in size depending upon the region. This is related to soil fertility, which provides the nutrient base for the plant communities that deer feed on.
Average Height: 3 to 4 feet tall at the shoulder
Average Weight: female 100 to150 pounds, male 150 to 250 pounds
Hair is reddish-brown to tan; in winter it turns to grayish-brown.
Throat, belly, inner rump, insides of the legs, and underside of the tail are white.
In Illinois, molt from winter to summer coat generally occurs in April and back to winter coat in September. The summer coat has finer hairs, providing better cooling but less protection from insects. The winter coat consists of brittle, hollow guard hairs that contain air which provides insulation and buoyancy for swimming.
Fawns are completely covered with hair when they are born. Their reddish coat has 250 to 350 white spots that creates a mottled pattern that blends with their surroundings, providing camouflage from predators. At 3 to 5 months of age fawns develop a coat similar to the adult winter coat.
Antlers are solid bone formations, not hollow like horns. They develop from the skin-covered pedicle on the frontal bone of a deer’s skull.
Antler growth is regulated by the melatonin hormone, which is controlled by day length. Antlers begin developing in early spring and are typically shed between late December and mid-March.
Antler shape, size, and composition are an expression of the genes received from the male’s parents, as well as of nutrition and his age.
For additional information, refer to Nutritional Requirements of White-Tailed Deer in Missouri.
During the active growth phase, antlers have a rich blood supply and are covered with short, bristly hairs known as velvet.
Growing antlers are composed primarily of proteins along with calcium, phosphorus, and smaller amounts of other minerals.
Antlers become larger and heavier each year, starting with buttons on a male fawn at 4 to 5 months and developing to the full rack by 6½ years.
The rack of a deer more than 6½ years of age usually loses its symmetry. Instead of the standard branched beam, it may develop many small tines.
By late summer, blood flow to the antlers ceases, causing the velvet to start drying out. Males begin rubbing off the sloughing velvet, polishing the hardened antlers in the process. Hardened antlers have low water and protein content, weakening the connection between the antler and skull, which leads to shedding of the antler. Most antler shedding occurs between late December and mid-March. Shed antlers usually do not last long because rodents gnaw on them for their mineral content, and weather softens the antler, returning the nutrients to the forest floor.
Atypical antler growth may be a result of genetics or injury. When genetically related, abnormal branching often occurs on both antlers. Antlers are most vulnerable to injuries during the growth stage. Deformation caused by injury can be permanent or temporary. Occasionally, antlers of some deer appear palmated—filled in between the tines like a moose—which is an inherited trait.
The uncommon females with antlers are of two types: those with velvet-covered antlers and a female reproductive tract able to bear young; and those with polished antlers that are male pseudo-hermaphrodites and have the external genitalia of a female but internally possesses male organs. Females that lack the ability to regulate the hormone testosterone may grow antlers.
Collecting Shed Antlers
Go to the Illinois Digest of Hunting and Trapping for current rules on collecting shed antlers.
Studies have shown that deer can detect human scent on underbrush for days and that cautious males react negatively to the scent, often remaining wary of the area for weeks. Deer can detect odors over 100 times better than people can because deer have millions more nasal receptors that help them distinguish between odors.
A deer’s ears can move independently to focus on sounds. Deer have better high-frequency but poorer low-frequency hearing than humans.
- Large eyes on the sides of the head allow deer to see ahead and behind without moving their heads, giving them approximately a 310˚ field of vision.
- Deer’s eyes are highly sensitive to light, and deer can see well during the day and at night.
- While white-tailed deer generally see in shades of gray, they are able to distinguish shades of blue, yellow, and green; they are less able to distinguish in the orange and red wavelengths.
- Deer hunters wear blaze orange or blaze pink because both colors stand out to people, but deer are unable to see these colors.
- A tissue (tapetum) in a deer’s eye enhances vision in low-light conditions. When a light is shone in a deer’s eyes, the captured light is reflected back through the retina, making the eyes shine.
Deer make a range of vocalizations, including but not limited to these:
Bleats—Fawns bleat like lambs.
Blows—Males and females may blow or whistle.
Grunts—Males often call during the mating season.
Snorts—A deer’s snorts alert the herd of an approaching threat.
Snort-wheeze—Males make this classic noise during the breeding season.
Forehead: Glands located on the foreheads of deer leave a scent behind when they rub on vegetation. All deer use these secretory glands during the rutting season, but dominant males make the most use of them.
Preorbital: These glands are located in the forward corner of the eye, and gland secretions serve to cleanse the eye.
Nasal: Scientists are uncertain as to the purpose of the nasal gland other than lubricating the nose.
Preputial: This gland is located inside the penis sheath and consists of greatly enlarged sebaceous glands.
Tarsal: Located inside the hind leg at the hock, or crook, this gland plays an important role in communication, social dominance, and reproductive activities and is considered the most important gland. Deer urinate with their legs together, rubbing while urinating over the glands. Males use this behavior to display social dominance. Incidentally, removal of the tarsal and metatarsal glands upon killing a deer is unnecessary because all functions cease once the deer is dead. By cutting these glands, the knife can become contaminated and spread scent throughout the rest of the carcass and spoil the meat.
Metatarsal: This gland is located on the outside of the hind leg, above the toes of the deer, and is ringed with white hair. The role it plays is uncertain.
Interdigital: The interdigital glands, found between the toes on each foot, are used by deer as an aid in tracking other deer. As the hoof is carried through vegetation or placed on the ground, scent from a waxy secretion is left where the deer has walked. This can be used as a means for does to track their young or for bucks trailing does during rut. Dominant males have higher concentrations of certain compounds in their gland’s secretions than subordinate males, thus informing other deer of their social status.