Odocoileus virginianus

Pelage is tan or reddish brown in summer, grayish brown in winter. Ears are large and may move independently. Males have antlers with one main beam and unbranched tines. Upper side of tail is brown with a white edge (often a darker stripe down the middle), white on the underside. Juveniles have spotted pelage.

White-tailed deer occupy many types of habitats in mountains and lowlands, including various forests and woodlands, forest edges, shrublands, grasslands with shrubs, and residential areas. They are often associated with successional vegetation, especially near agricultural lands. In the north in winter, they tend to be in areas with minimal snow cover (if possible) and often use stands of conifers for shelter. Within arid regions, white-tailed deer prefer mesic situations (riparian zones, montane woodlands).

Two basic social groups: adult female(s) and young, and adult and occasionally yearling males (though adult males are solitary during the breeding season except when attending estrous females).

Home range 16-120 ha (40-300 acres) (Banfield 1974); varies with conditions, smallest in summer. Annual home range of sedentary populations averages 59-520 ha (Smith 1991). Some populations undergo annual migrations of 10 to 50 kilometers (Marchinton and Hirth 1984).

Population density 1 per 6-46 acres, depending upon environmental conditions (Baker 1983). In some areas density may exceed 50/sq km (Rooney 1995).

Dispersal from mother's home range is mostly by yearling males. In Minnesota, 7 of 35 yearling females dispersed 18-168 km from natal ranges during late May through June; dispersal was independent of deer density (Nelson and Mech 1992); 95% of all yearlings dispersed not more than 38 km (Nelson 1993). Home range formation may extend over 2-3 years.

Winter weather (snow accumulation) may strongly affect populations, even more so than density of wolves in areas where the latter are present (Mech et al. 1987, Potvin et al. 1992). In many areas, coyotes or domestic dogs are significant predators.

White-tailed deer carry and disperse into the environment meningeal worms that usually are fatal to moose and caribou but are clinically benign in deer; hence, white-tailed deer, through worm-mediated impacts, commonly are believed to exclude moose and caribou from areas where deer occur; however, an analysis by Schmitz and Nudds (1994) concluded that moose may be able to coexist with deer, albeit at lower densities, even in the absence of habitat refuges from the disease. Also, Whitlaw and Lankester (1994) found that the evidence that brainworm has caused moose declines is weak. Further study is needed.

Deer browsing may significantly impact vegetation characteristics (e.g., Anderson 1994).

Breeding occurs from late October to mid-December; with a peak in November. Female receptive period lasts 1-2 days; if not impregnated, a female becomes receptive again in 3-4 weeks. Gestation varies among populations from 187 to 222 days. Litter of usually 1-2 (sometimes 3 in optimal habitat) is born in May-June. Young initially stay hidden for 1-2 weeks and are weaned usually by 10 weeks postpartum (by fall). Females first breed sometimes at 6-7 months or more typically at 1.5 years; males are sexually mature at about 18 months. Few live more than 10 years.