The White-tailed deer, also called the Virginia deer or whitetail, is named for the white underside of its tail which is visible when it holds its tail erect when it runs. Adults have a bright reddish-brown coat in the summer and in the winter it is a duller grayish brown. The young have white spots on their reddish coats.
White-tailed deer occur in most of southern Canada and all of the United States mainland except for a couple of western states. Their range covers entire Mexico and Central America reaching to South America as far south as Peru and Bolivia. They live in a range of habitats, from big woods in northern Maine to Florida's hammock swamps and deep saw grass. They also occupy farmland, brushy areas, and some desolate areas in the west like the thornbrush and cactus deserts of Mexico and southern Texas.
White-tailed deer are usually considered solitary, particularly in summer. Their basic social unit is mother and fawns, although sometimes they do graze together in herds that can number hundreds of individuals. Bucks and does remain separate from each other except during the mating season. Bucks usually live alone or within small groups alongside other bucks. Deer living in deserts often migrate from summertime elevations down to warmer areas where there is more food available. White-tailed deer are crepuscular, and mainly feed starting before dawn until a few hours after the sun has risen, and again in the late afternoon until dusk. They use a number of forms of communication, such as sound, odor, body language, and marking with scratches. When alarmed, a White-tailed deer will raise its tail to warn other deer.
Whitetails are herbivores and feed on twigs, bark, leaves, shrubs, the nuts and fruits of most vegetation, lichens, and other fungi. Plants such as yucca, huajillo brush, prickly pear cactus, ratama, comal, and a range of tough shrubs can be the mainstay of a whitetail's diet if it lives in a desert area. Though almost entirely herbivorous, White-tailed deer have may opportunistically feed on nesting songbirds, field mice, and birds trapped in mist nets, if the need arises
Whitetails are polygynous, and bucks fight fiercely during the mating season, with winners able to mate with does in the area. The season runs from October to December. The gestation period is about 6 months. A female usually gives birth to one fawn in her initial year of breeding but 2 are born subsequently. Fawns can walk as soon as they are born and only a few days later are able to nibble on vegetation. When seeking food, mothers leave their offspring hidden amongst vegetation. A fawn starts to follow its mother as she goes off to forage when it is about 4 weeks old. At 8 - 10 months old, they are weaned. At one-year-old, young males leave their mothers but young females will often stay with them for two years. Most of them (particularly males) will breed in their second year.
Being commonly hunted for sport and meat, and in Texas being the primary big game animals, White-tailed deer populations are threatened by overhunting. To the south from the US border deer face this same threat, along with habitat loss. Poaching is another cause of the extinction of local populations.
The United States White-tailed deer population is estimated to be over 11,000,000 individuals, of which a third will be in the State of Texas. The estimated population in Canada is half a million individuals. Overall, whitetails’ numbers are stable currently and they are classified as least concern (LC) on the list of Threatened species, but in Mexico, Central America, and South America most of the populations are declining.
White-tailed deer can have a great influence on plant communities as a result of their grazing, particularly where they are abundant. These deer are also an important prey animal for many large predators.