SCIENTIFIC NAME:
Odocoileus virginianus
OTHER NAMES:
Whitetail Deer, Whitetail, Virginia Deer
STATUS:
This common and important game species is a browser and grazer found statewide, including urban habitats. Lowest Conservation Concern.
DESCRIPTION:
White-tailed deer (Odocoileus virginianus) are some of the most recognized wildlife in Alabama. Two seasonal molts produce two distinctly different coats. The summer coat consists of short, thin hairs that are reddish-brown in color. This coat is molted in August and September and is replaced with the winter coat, which consists of longer, hollow grayish brown hairs over a short wooly undercoat. The hollow hairs and the wooly undercoat provide significant insulation against cold winter weather. The winter coat is replaced by the summer coat in April and May. A deer’s belly, chest, throat, and chin are white throughout the year. The coats of newly born fawns are reddish-brown with several hundred small white spots. This spotted coat helps conceal them from predators. A fawn’s spotted coat is replaced by the brownish-gray winter coat at approximately three to four months of age. Deer with aberrant color phases are not uncommon in Alabama. A pure white (albino) or black (melanistic) deer is indeed rare. However, harvests of piebald deer are fairly common throughout Alabama. Piebald deer are characterized by having an almost all-white coat with some brown splotches present.
Deer have an excellent sense of smell. Their elongated noses are filled with an intricate system of nasal passages that contain millions of olfactory receptor sites. Their keen sense of smell is very important for avoiding predators, identifying other deer, and identifying food sources. Perhaps most importantly, their sense of smell is important for scent communication with other deer. Deer have seven glands that are used primarily for scent communication.
Deer also have an excellent sense of hearing. Large, moveable ears allow them to detect sounds at great distances and pinpoint the direction of these sounds. Deer have numerous vocalizations, including various grunts, bawls, mews, whines, wheezes, and snorts.
Female deer, or does, typically are smaller framed and weigh less than male deer, or bucks, of the same age. At shoulder height, a doe is about 36 inches tall, with bucks of similar ages being slightly taller. In Alabama, weights of healthy adult does may range from less than 90 to more than 140 pounds, while healthy adult males may range from 140 pounds to more than 250 pounds, depending on age and habitat quality. At birth, most fawns weigh four to eight pounds and stand about 18 inches tall at the shoulder.
Bucks grow antlers each year, beginning at one year of age. Antler growth usually begins in late April or May and is completed by September. Antlers are typically shed in March. Bucks typically grow larger antlers each year until antler size peaks at around five to seven years old. Antler size and shape are highly variable and depend on age, nutrition, and genetics.
Approximately 38 subspecies of white-tailed deer have been described in North, Central, and South America. Thirty of these subspecies are found in North and Central America alone.
DISTRIBUTION:
Deer were rare in most of Alabama until recent years. In the early 1900s, it was estimated only about 2,000 deer existed in the entire state. After decades of restocking and management efforts, Alabama’s deer population was estimated at 1.75 million animals in 2000. In fact, many areas in Alabama are overpopulated with deer and have been for many years. As a result, crop damage, deer/vehicle collisions, and other negative deer/human interactions have become more common. Historically in Alabama, the predominant subspecies of whitetail was the Virginia subspecies (O. v. virginianus), with the subspecies O. v. osceola inhabiting the extreme southern edge of the state. Following the near extirpation of whitetails from the state in the early 1900s, the Alabama Department of Conservation, along with some private individuals and groups, began restocking deer throughout the state in the 1930s. Most restocking occurred during the 1950s and 60s.
The majority of deer restocked in Alabama were from sources within the state and assumed to have been O. v. virginianus. Deer from several other states, including Arkansas, Georgia, Michigan, North Carolina, Ohio, Texas, and Wisconsin, were used to a much lesser degree in restocking several areas around Alabama. Those restockings included deer from as many as six different subspecies of whitetails, including O. v. borealis, O. v. macrourus, O. v. osceola, O. v. seminolus, O. v. texanus, and O. v. virginianus. Due to the variety of stocking sources, many locations in Alabama may contain deer with a combination of ancestries that cannot be placed in a single subspecies. As a whole, it is assumed the majority of deer in Alabama are of the Virginia subspecies since 56 of the state’s 67 counties were stocked using this subspecies.
HABITAT:
White-tailed deer are highly adaptable to various habitat types, as well as sudden changes in habitat composition. They can survive in areas of mature timber, as well as areas with extensive open areas. For this reason, they are found in virtually all habitat types in Alabama. Deer are creatures of edge and do best in areas with a diversity of habitat types. No single homogenous habitat type is ideal for deer, whether mature hardwoods or pine plantations. Simply put, deer need food, water, and cover in a suitable arrangement. Good deer habitat consists of a variety of components. Life and nutritional requirements of deer vary throughout the year, so good deer habitat has sufficient quantity and quality of each component available throughout the year.
FEEDING HABITS:
On average, deer eat four to six pounds of forage daily for each 100 pounds of body weight. An average-sized deer consumes more than a ton of forage per year. Deer are ruminants (cud-chewers), and like cattle, have a compound, four-chambered stomach. By nature, deer are very selective feeders. They are browsers, not grazers. Their mouths are long and pointed for picking out specific food items, as opposed to being wide and shovel-like for consuming sheer quantities of forage. A deer’s diet is as varied as the habitats they utilize. Deer feed on the leaves, twigs, fruit, and shoots of a variety of trees, shrubs, and vines. Deer also feed on many weeds, grasses, agricultural plantings, and several species of fungi. Hard mast (acorns, etc.) is highly preferred when available. Unlike cattle, deer do not feed exclusively on a limited variety of forages. Deer are very specialized feeders and may only eat significant quantities of a small percentage of the total plant species occurring in their habitat. Certainly, when deer are nutritionally stressed by overpopulation, they will eat larger quantities of a wider variety of second and third choice foods.
LIFE HISTORY AND ECOLOGY:
White-tailed deer social structure outside of the breeding season is centered on two basic social groups: matriarchal and bachelor groups. Matriarchal groups are comprised of a maternal doe, her young of the year, and her female offspring from previous years. Bachelor groups are loose knit groups of adult bucks. The size of bachelor groups varies from two to more than 10 bucks.
Research has documented average conception dates in Alabama occurring around Thanksgiving, mid-December, early January, and even into early February. For most of Alabama, the peak of breeding season, or the rut, occurs around mid- to late January. During the rut, whitetail bucks undergo hormonal changes. Adult bucks become much more aggressive and less tolerant of other bucks. Bachelor groups typically breakdown at this time. Rutting bucks are characterized by large, swollen necks and a strong, musky odor resulting from increased rub-urination behavior. During this time, bucks mark and defend breeding territories by creating numerous rubs and scrapes within their home range. Rubs are both visual and scent signposts made by rubbing the antlers and forehead gland against small trees and saplings. Scrapes are important calling cards of adult bucks. A buck creates these areas of bare earth by pawing beneath an overhanging limb and urinating over his tarsal glands in a behavior called rub-urinating. The urine is infused with scent from the tarsal glands while the buck rubs his face, forehead gland, preorbital gland, and antlers on the overhanging limb. Bucks check their scrapes regularly to detect whether a receptive doe has visited the site and deposited urine as well. If so, the buck will use his sense of smell to trail the doe and attempt to breed her.
Does remain in heat or estrous and are receptive to breeding for about 24 hours. During that time, a courting buck will stay close to an estrous doe—even feeding and bedding with her. During her period of estrous, the buck may mate with her several times. If a doe is not bred during this period of receptiveness, she will come into estrous again about every 28 days until she is bred or until the breeding season is over. In some herds with unbalanced adult sex ratios, does may be bred on second, third, or even fourth estrous cycles. Yearling does (1 ½ years old) are sexually mature and capable of breeding. Research in Alabama has documented pregnancy rates for yearling does as high as 100 percent in healthy herds. State researchers also have documented doe fawns that were bred and had conceived, but this is rare. Yearling bucks also are capable of breeding. These bucks usually do very little breeding in herds with a normal buck age structure and adult sex ratio.
As parturition nears, pregnant does become solitary and defend fawning territories from other deer. Fawns are born approximately 200 days after conception. In Alabama, most fawns are born from late-July to mid-August. Studies in Alabama have shown births occurring as early as April and as late as November. Extremely late births may result from does being bred during their second, third, or later estrous cycles. The number of fawns produced depends on the age and physical condition of the doe. Generally, yearling does have a single fawn, but twins are not uncommon. Healthy adult does (two-and-a-half years and older) usually will have twins each year. Triplets have been documented with some regularity and, on rare occasions, quadruplets have been found. Deer herds in poor habitats that are grossly overpopulated may exhibit poor fawn production and survival. Often pregnancy rates for does in poor condition may be below 75 percent. Does rarely venture more than 100 yards from their fawns during the first few days following birth. Fawns begin accompanying their mothers at three to four weeks old.
REFERENCES:
Allen, R. H. 1965. History and Results of Deer Restocking in Alabama, Bulletin No. 6. Alabama Department Of Conservation, Montgomery, AL. 50 pp.
Baker, R. H. 1984. Origin, Classification, and Distribution. Pages 1-18 In L. K. Halls, Ed. White-Tailed Deer: Ecology and Management. The Wildlife Management Institute, Washington, D.C.
Cook, C., and B. Gray. 2003. Biology and Management of White-Tailed Deer in Alabama. Alabama Department of Conservation and Natural Resources, Montgomery, AL. 175 pp.
Davis, J. R. 1979. The White-Tailed Deer in Alabama, Special Report Number 8. P-R Project W-35, Alabama Department of Conservation and Natural Resources, Montgomery, AL. 60 pp.
Marchinton, R. L., and D. H. Hirth. 1984. Behavior. Pages 129-168 in L. K. Halls, ed. White-Tailed Deer: Ecology and Management. The Wildlife Management Institute, Washington, D.C.
McDonald, J. S. and K. V. Miller. 1993. A History of White-Tailed Deer Restocking in the United States 1878 to 1992. Research Publication 93-1. The Quality Deer Management Association, Watkinsville, Georgia. 109 pages.
Miller, K. V., R. L. Marchinton, and J. J. Ozoga. 1995. Deer Sociobiology. Pages 118-128 in K. V. Miller and R. L. Marchinton, Eds., Quality Whitetails – The Why and How of Quality Deer Management. Stackpole Books, Mechanicsburg, Pennsylvania.
Miller, K. V., L. I. Muller, S. Demarais. 2003. White-Tailed Deer. Pages 906-930 in G. A. Feldhamer, B. C. Thompson, and J. A. Chapman, Eds. Wild Mammals of North America: Biology, Management, and Conservation. Second Edition. The Johns Hopkins University Press, Baltimore, MD and London, U.K.
Nowak, R. M. 1999. Walker’s Mammals of the World, Sixth Edition, Volume Two. The Johns Hopkins University Press, Baltimore, MD and London, U.K. 903 pp.
Sauer, P. R. 1984. Physical Characteristics. Pages 73-90 in L. K. Halls, ed. White-Tailed Deer: Ecology and Management. The Wildlife Management Institute, Washington, D.C.
Author:
Chris Cook, Wildlife Biologist, Alabama Division of Wildlife and Freshwater Fisheries